Travel

The NSSC provides travel reimbursement services for all authorized Agency travel including: domestic, foreign, local, ETDY, and Change of Station (COS).

References

Federal Travel Regulations (FTR)
Traveler Extended TDY and Taxes
Domestic Per Diem Rates
Foreign Per Diem Rates

Change of Station

NSSC Travel now has another way that a transferee Traveler may submit his or her vouchers. Please see, submitting Change of Station Process Steps

If traveling CONUS, review: NASA’s Guide to a Successful Move (CONUS)

If traveling OCONUS, review: NASA’s Guide to a Successful Move (OCONUS)

Change of Station References

Change of Station Voucher Information And Samples

Allegiance POC Information

GSA Smart Pay State Tax Information

Change of Station and RITA

Change of Station ServiceNow Instructions

Change of Station Forms

NSSC Change of Station Form

OF 1012 Travel Voucher 

SF 1038 Advance of Funds Application and Account

NASA Form 1815 Tax Exemption Certificate (Tax on Occupancy of Hotel Rooms)

NF420  Service Agreement-First Duty Station Appointment

NF513 Service Agreement and Duplicate Reimbursement Disclosure Statement OCONUS Employment

NF1204 Employee’s Claim for Damage to, or Loss of, Personal Property Incident to Service

NF1337 Service Agreement-Transferred Employee

NF1338 Employee Application for Reimbursement of Expenses Incurred upon Sale or Purchase (or both) of Residence upon Change of Station

NF1449C  CONUS-Information Covering Persons Transferred or Appointed to First Duty Station

NF1449O OCONUS-Information Covering Persons Transferred or Appointed to First Duty Station

NF1450C CONUS Change of Station Authorization

NF1450O OCONUS Change of Station Authorization

NF1500 Claim for Temporary Quarters Subsistence Expense/Temporary Quarters Subsistence Allowance Reimbursement

NF1807 Househunting Trip Binding Decision

NF1808 Property Management Binding Decision

NF1809 Temporary Quarters Subsistence Expenses (TQSE) Binding Decision

NF1810 Employee Agreement to Repay Withholding Tax Allowance (WTA)

NF 1811 Temporary Quarters Subsistence Allowance (TQSA)

NF1812 Temporary Quarters Subsistence Allowance (TQSA) Preceding Final Departure

NF1813 Temporary Change of Station (TCS) Duplicate Reimbursement Disclosure Statement

NF1814 Temporary Quarters Subsistence Allowance (TQSA) Predeparture Binding Decision

Related Tax Information:

Check out the latest Taxability Change Notice for Change of Station travelers.
To learn more, see: Relocation Income Tax Allowance Information

Domestic Travel

POV Mileage for NASA Travelers
For Privately Owned Vehicle (POV) Mileage Reimbursement Rates for TDY and ETDY Travel please refer to the GSA Web site: http://www.gsa.gov/mileage   

NASA Domestic Travel: Day that Travel Ends
For the day travel ends (the day a traveler returns to the PDS, home, or other authorized point), the per diem allowance is 75% of M&IE. 

NASA Domestic Travel Rental Car Liability

When making a reservation for a rental car, please remember the Government is only responsible to pay for rental car charges for official travel time.  If a traveler decides to take annual leave in conjunction with official travel and keeps the rental car during annual leave, the portion of the rental rate applicable to annual leave is the responsibility of the traveler.  Please refer to 41 CFR 301-10.453

What is my liability for unauthorized use of a rental automobile obtained with Government funds?

You are responsible for any additional cost resulting from the unauthorized use of a commercial rental automobile for other than official travel-related purposes.

NASA Domestic Travel: Tax Exemption

Prior to traveling, refer to the GSA State Tax Information webpage: https://smartpay.gsa.gov/smarttax. Select your State/US territory of interest to see the exemption status and download the appropriate form, if required.

Extended Temporary Duty (ETDY)

Reduced Per Diem rate

NASA’s standard reduced per diem rate for ETDY travel is 65 percent under the current policy as defined in the NASA Procedural Requirements (NPR) 9750.1-3.1.2.

     a.   Consistent with 41 CFR 301-11.200, an ETDY authorization can include reasonable further reductions from this standard rate or limitations on approved lodging for unique circumstances, to the extent it can be  determined in advance that such will substantially lower costs without mission impact.  For example, if lodging is obtained at 50 percent per diem, the ETDY authorization should be adjusted to authorize a lower rate. 

    b.   The reduced rate of reimbursement begins on the first day of travel regardless of the mode of transportation, except as noted in 3.1.3.  Allowances are covered by the reduced per diem rate; therefore, NASA will authorize the employee a per diem rate (up to 65 percent) to reasonably cover expenses for a one bedroom furnished apartment.  For ETDY greater than 90 days, first consideration should be given to long-term lodging facilities.  Long-term lodging facilities are available on the GSA schedule at http://www.gsa.gov.  If a long-term facility is not selected, proper justification should be provided. 

Find more about Allowable ETDY Expenses Included in Reduced Per Diem Rate, please see the following document: 

Allowable ETDY Expenses Included in Reduced Per Diem Rate

GSA Long-term Lodging (Schedule 48)

GSA’s Schedule 48 is designed for lodging needs of 30 days or more. This program provides housing accommodations for temporary or permanent relocation. Typical facilities include apartment or condominium type properties that may be furnished with all the amenities of a regular home. The current list of vendors is available by clicking on the link above. Most of these properties will accommodate NASA Extended TDY travelers within the 65% reduce per diem rate and will allow use of the government charge card.

Foreign Travel

Please consult the Code of Federal Regulations (CFR), NPR 9710.1, and NPR 9750.1. Please call the NSSC Contact Center at 1-877-NSSC-123 (1-877-677-2123) for additional information.

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NASA

Twin NASA Satellites Ready to Help Gauge Earth’s Energy Balance

Information from the PREFIRE mission will illuminate how clouds and water vapor in the Arctic and Antarctic influence the amount of heat the poles radiate into space.

A pair of new shoebox-size NASA satellites will help unravel an atmospheric mystery that’s bedeviled scientists for years: how the behavior of clouds and water vapor at Earth’s polar regions affects our planet’s climate.

The first CubeSat in NASA’s Polar Radiant Energy in the Far-InfraRed Experiment (PREFIRE) mission launched from New Zealand on Saturday, May 25. The second PREFIRE CubeSat is targeted to lift off on Saturday, June 1, with a launch window opening at 3 p.m. NZST (11 p.m. EDT, Friday, May 31).

The mission will measure the amount of heat Earth emits into space from the two coldest, most remote regions on the planet. Data from PREFIRE will improve computer models that researchers use to predict how Earth’s ice, seas, and weather will change in a warming world.

Earth absorbs a lot of the Sun’s energy in the tropics, and weather and ocean currents transport that heat toward the poles (which receive much less sunlight). Ice, snow, and clouds, among other parts of the polar environment, emit some of that heat into space, much of it in the form of far-infrared radiation. The difference between the amount of heat Earth absorbs at the tropics and that radiated out from the Arctic and Antarctic is a key influence on the planet’s temperature, helping to drive dynamic systems of climate and weather.

But far-infrared emissions at the poles have never been systematically measured. This is where PREFIRE comes in. The mission will help researchers gain a clearer understanding of when and where Earth’s polar regions emit far-infrared radiation to space, as well as how atmospheric water vapor and clouds influence the amount that escapes.

Clouds and water vapor can trap far-infrared radiation on Earth, thereby increasing global temperatures — part of the greenhouse effect.

“It’s critical that we get the effects of clouds right if we want to accurately model Earth’s climate,” said Tristan L’Ecuyer, a professor at the University of Wisconsin-Madison and PREFIRE’s principal investigator.

Clouds in Climate Modeling

Clouds and water vapor at Earth’s poles act like windows on a summer day: A clear, relatively dry day in the Arctic is like opening a window to let heat out of a stuffy room. A cloudy, relatively humid day traps heat like a closed window.

The types of clouds — and the altitude at which they form — influence how much heat the polar atmosphere retains. Like a tinted window, low-altitude clouds, composed mainly of water droplets, tend to have a cooling effect. High-altitude clouds, made mainly of ice particles, more readily absorb heat, generating a warming effect. Because clouds at mid-altitudes can have varying water-droplet and ice-particle contents, they can have either a warming or cooling effect.

But clouds are notoriously difficult to study: They’re made up of microscopic particles that can move and change in a matter of seconds to hours. When it rains or snows, there’s a great reshuffling of water and energy that can alter the character of clouds entirely. These ever-changing factors complicate the task of realistically capturing cloud behavior in climate models, which try to project global climate scenarios.

Inconsistencies in how various climate models represent clouds can mean the difference between predicting 5 or 10 degrees Fahrenheit (3 or 6 degrees Celsius) of warming. The PREFIRE mission aims to reduce that uncertainty.

The thermal infrared spectrometer on each spacecraft will make crucial measurements of wavelengths of light in the far-infrared range. The instruments will be able to detect clouds largely invisible to other types of optical instruments. And PREFIRE’s instruments will be sensitive enough to detect the approximate size of particles to distinguish between liquid droplets and ice particles.

“PREFIRE will give us a new set of eyes on clouds,” said Brian Kahn, an atmospheric scientist at NASA’s Jet Propulsion Laboratory and a member of the PREFIRE science team. “We’re not quite sure what we’re going to see, and that’s really exciting.”

More About the Mission

PREFIRE was jointly developed by NASA and the University of Wisconsin-Madison. A division of Caltech in Pasadena, California, JPL manages the mission for NASA’s Science Mission Directorate and provided the spectrometers. Blue Canyon Technologies built the CubeSats, and the University of Wisconsin-Madison will process and analyze the data the instruments collect.

NASA’s Launch Services Program selected Rocket Lab to launch both spacecraft as part of the agency’s Venture-class Acquisition of Dedicated and Rideshare (VADR) contract. CubeSats like PREFIRE serve as an ideal platform for technical and architecture innovation, contributing to NASA’s science research and technology development.

To learn more about PREFIRE, visit:

https://science.nasa.gov/mission/prefire/

News Media Contacts

Jane J. Lee / Andrew Wang
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0307 / 626-379-6874
jane.j.lee@jpl.nasa.gov / andrew.wang@jpl.nasa.gov

2024-076

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Anthony Greicius

Summary of the 2023 GRACE Follow-On Science Team Meeting

Felix Landerer, NASA/Jet Propulsion Laboratory, felix.w.landerer@jpl.nasa.gov

Introduction

In October 2023, the annual gathering of the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On [G-FO] Science Team took place in Boulder, CO, hosted at University Corporation for Atmospheric Research’s (UCAR) Center Green campus. The event had 70 in-person participant and an additional 52 online participants – see Photo. G-FO is a U.S.–German collaboration between NASA and the Helmholtz Centre Potsdam GeoForschungsZentrum (GFZ) [German Research Centre for Geosciences].

The meeting agenda featured 15-minute presentations over three days, describing new findings from G-FO observations and the combined GRACE and GRACE-FO [G/G-FO] climate data record that now spans over 21 years (2002–2023). 

The meeting began with the customary G-FO project status session, covering programmatic mission and flight segment technical updates, future mission plans, and descriptions of the latest data released from the GRACE Science Data System (SDS) centers. Subsequent sessions featured more than 53 contributed presentations covering analyses, algorithms, and science results by Science Team members and attendees, totaling 57 oral and 5 poster presentations. Many of the presentations are posted on the GRACE website. While this summary will cover all the content on the agenda of the meeting – it does do so in an exact linear fashion. It begins with a G-FO mission status update, followed by key highlights from the contributed analysis and science presentations.

Status of GRACE Follow-On

Since their launch on May 22, 2018, the twin G-FO satellites have been tracking Earth’s water movements and global surface mass changes that arise from climatic, anthropogenic, and tectonic changes. G-FO also enables new insights into variations of ice sheet and glacier mass, land water storage, as well as changes in sea level and ocean currents. These measurements have important applications and implications for everyday life. The impact of these data is underscored by the publication of over 6000 scientific papers – an average of 5 new publications per week – that have established G/G-FO as a leading Earth Science mission.

In May 2023, G-FO successfully completed its Prime Mission phase that lasted five years after launch. G-FO was among the missions that went through the 2023 NASA Earth Science Senior Review. The NASA project team submitted its response in spring of 2023 to extend mission operations through 2026. The proposal received overall Excellent score, highlighting the unique utility the data provide for Earth Science research and societal applications. However, the G-FO project’s NASA budget will be reduced (compared to the previous baseline) by 15% in fiscal year (FY) 2024 and 24% in FY 2025 and 2026 due to the overall budget constraints that NASA is facing. The G-FO team remains confident in its ability to continue delivering high-value and high-impact science data products – prioritizing science operations management and data latency over data reprocessing campaigns. Both NASA and GFZ had already formally committed to extending their collaboration on G-FO mission operations and data processing through the end of 2026 via a Memorandum of Understanding.

As of December 2023, the G-FO project team has processed and released 62 monthly gravity fields – the most recent being for October 2023 (at the time of this writing). The primary mission objective for G-FO is to provide continuity for the monthly GRACE mass-change observations (2002–2017) via its Microwave Interferometer (MWI) intersatellite range-change observations. G-FO also demonstrated a novel technology demonstration Laser-Ranging Interferometer (LRI) for more accurate satellite-to-satellite ranging observations for future GRACE-like missions. The LRI has been successfully operated in parallel with the MWI for most of the mission, delivering excellent quality data. LRI-based monthly gravity and mass change fields covering the period from mid-2018 to mid-2023 have been made available by the SDS teams for further analysis and study by the science community. 

Programmatic, Mission, and Operations Updates

The meeting began with Frank Flechtner [GFZ–German G-FO Project Manager] and Felix Landerer [NASA/Jet Propulsion Laboratory (JPL)—U.S. G-FO Project Scientist] giving welcoming remarks, followed by detailed assessments of the G-FO mission and operations status from the core SDS centers and flight operations teams.

GRACE Follow-On Project Status

Felix Landerer gave an overview of the G-FO satellites and the science data system performance. He reported that G-FO continues to meet its goal of extending the GRACE mass-change and gravity data record at equivalent precision and spatiotemporal sampling. 

Since the previous STM in October 2022, the overall G-FO science instrument performance has been stable, and the SDS team continued to deliver a gapless monthly data record to users ahead of schedule (on average, within 43 days instead of the 60-day requirement). Improving the data calibrations of the accelerometer measurements – which are noise contaminated on one of the two G-FO spacecraft – remains a core focus of the project SDS team. To this end, an improved calibration approach that reduced data errors by 10–20% has been developed and will be operationalized by the team in the coming months. 

Landerer reported that, as forecasted, the current Solar Cycle 25 has gained in strength through 2023 and will continue to do so through 2024 before subsiding again. The resulting higher non-gravitational forces acting on the satellites need to be properly accounted for in the accelerometer data processing. 

He also noted that small thruster leaks in the satellites cold gas propulsion system have been closely monitored since 2021. To ensure stable data collection and sufficient lifetime margin to achieve continuity with the proposed successor mission GRACE-Continuity, or GRACE-C (which is the new name for the Earth System Observatory Mass Change mission scheduled for launch no earlier than 2028), the G-FO project team, in conjunction with guidance from the satellite manufacturer Airbus and the German Space Operations Center, decided to adjust the operational data collection mode of G-FO to a wide pointing mode – which means that the two spacecraft are allowed to deviate from their relative line-of-sight pointing by up to 2°, whereas the previous pointing angles were 100 times smaller. This operational change necessitates fewer thruster firings, which in turn reduces leaks and improves accelerometer calibrations – and thus leads to better overall science data quality. Due to the wide pointing, the LRI intersatellite ranging data collection has been suspended in this operational mode. However, the LRI instruments are still activated and fully functional. Landerer emphasized that reducing the leak ensures that the GRACE-FO mission will have sufficient fuel to remain operational up until GRACE-C launches.

Despite these operational challenges, Landerer said that the science data delivered by G-FO continues to provide excellent utility and insights into a rapidly changing Earth system. He briefly highlighted a few scientific and decision-support contributions and achievements of G-FO over the last year. These included: 

• Monitoring California Groundwater. G-FO recorded the largest seasonal total water storage gains over California after the multiple atmospheric rivers made landfall during the 2022/2023 winter. Yet, peak water storage in May was below values observed 15–20 years ago – due to long-term, sustained groundwater declines. Going forward, the data will be invaluable to assess groundwater recharge rates and processes.

• Observing Water Cycle Extremes: Droughts and Pluvials. The G-GFO 20-year data record has been analyzed to show the increasing intensity of wet and dry extremes of the global water cycle, which increased as global temperatures rose.

• Tracking Polar Ice Mass Loss. G/G-FO measured net ice mass gains over Antarctica that began around 2021 due to snow accumulation mainly in East Antarctica, which offset the unabated mass loss of the West Antarctic ice sheet.

Subsequent science presentations presented in-depth analyses of these and other findings in the dedicated science sessions, some of which are summarized below. 

Landerer also highlighted the expanding portfolio of open science contributions that the project team is supporting: Jupyter notebooks are part of an expanding GRACE Open Science toolbox with the goal to expand this toolbox with input from the Science Team and user community in the coming years. In addition, easy-to-use browser data portals at JPL and GFZ have been key to expand the science and applications user community that increasingly use the Level-3 and higher data products in decision support contexts (e.g., for drought monitoring and water resources management).

A series of status reports on programmatic G-FO mission operations, science operations, and SDS processing followed the opening presentations. Krzysztof Snopek [GFZ] reported on the ground and mission operations at the German Space Operations Center (GSOC), which is responsible for G-FO spacecraft operations. All essential flight operations, software updates, and planned calibrations were successfully scheduled and carried out by GSOC. Himanshu Save [University of Texas, Center for Space Research (CSR)] provided the science operations assessment. He described the evolving Solar Cycle 25 and its influence on the G-FO spacecraft, the mission’s fuel budget, and adjusted operational procedures and modes (such as the already-mentioned ‘wide’ pointing mode). Christopher McCullough [JPL] reviewed the status of G/G-FO Level 1 processing at JPL, detailing additional improvements made in the accelerometer calibrations. The team is using the noisy accelerometer data on one satellite and retrieving improved science information from it.

A representative from each of the G-FO mission SDS centers – which includes JPL, GFZ, CSR, and GSFC – summarized the status of the latest gravity-field and mass change data products [RL06.X L2], including an overview of background dealiasing models and the GFZ GravIS portal, the updated JPL mascon data product, new data-processing strategies, e.g., via range acceleration [CSR], and the status of ancillary Satellite-Laser-Ranging (SLR) data processing and dedicated G/G-FO products [GSFC].

Following the project team’s status presentations, there was a 30-minute session to answer questions from the science community and discuss in more detail the mission performance, near-term operations and data processing plans, as well as to gather suggestions and feedback from the community. 

Science Presentations

The remainder of the sessions in the meeting were open-submission science sessions, each of which centered around different thematic topics, including: G/G-FO analysis techniques and next generation gravity mission (NGGM) concept studies, and science analysis of mass-transport data in the fields of glaciology, oceanography, hydrology, and solid-Earth physics. As has been the case in previous years, the presenters underscored the value of interdisciplinary and multi-instrument analyses that utilize the unique complementary value of G/G-FO mass-change observations in combination with other remote sensing data (e.g., satellite altimetry or precipitation observations) and in situ data (e.g., surface deformation or ocean temperature profiles). Such hydrogeodetic combinations yield improved spatial and temporal resolutions that enable advances in Earth system process understanding, which increasingly advance societal applications of science results in support of NASA’s programmatic focus on Earth Science to Action, which seeks to “advance and integrate Earth science knowledge to empower humanity to create a more resilient world.”

Section A: GRACE and GRACE-FO Geodesy

The project status reports presented under the previous heading were part of the first section of the agenda (Session A1) as were two additional sessions: Analysis Techniques and Intercomparisons (Session A2) and NGGM and Bridging the Gap (Session A3), which focused on plans, concepts, and technologies being developed for future gravity missions. Highlights from each of these two sessions follow in the next two subsections. 

Analysis Techniques and Inter-comparisons

This session featured 15 presentations by the SDS centers and ST members on progress in instrument data calibrations and novel data processing algorithms and methods, including data-fusion with other observations.

Representatives from G/G-FO processing centers presented updated gravity-field time-series data, which capitalize on improved parameterizations, better instrument error characterizations (e.g., from star cameras, accelerometers, or ranging instruments) and background models (e.g., for tides) for improved monthly mass change data and uncertainty quantification. The highly accurate LRI data provides further opportunities to identify and characterize measurement system errors, which can be exploited for G-FO data processing but is also informative in the development of the future GRACE-C mission. However, it was also shown that several metrics used in identifying gravitational errors are sensitive to the estimated satellite trajectory, and consequently a sufficient understanding of the orbital trajectory is necessary to make accurate adjustments to the gravity field based on satellite observations.

The G/G-FO data products make use of ground-based geodetic observations, such as satellite laser-ranging (SLR) to a network of dedicated SLR satellites, which can be used to extend the G/G-FO interannual data record back to ~1994 – albeit at a much-reduced spatial resolution. Additionally, SLR data provide an important validation and performance assessment opportunity for G/G-FO observations. In that regard one presenter showed results indicating the recent G-FO accelerometer updates have indeed resulted in better gravity and mass change fields. Other speakers discussed the value and potential for improvement that could be achieved by combining G-FO and SLR observations more formally to exploit the data strengths of the different observation types in an optimal way. Such approaches could reduce uncertainties in global ocean and land ice mass changes. Furthermore, deployment of stable, long-term ocean bottom pressure (OBP) recorders in the Arctic Ocean in 2022 has enabled progress on G/G-FO OBP data validation. The data from these OBP recorders are entirely independent of G/G-FO observations and are thus very valuable to assess the satellite data record. An initial comparison between 1.5 years of OBP data and various G-FO OBP products suggest excellent agreement.

The data collected from G/G-FO has a native resolution of about 300 km (~186 mi). By jointly analyzing these G/G-FO data with higher-resolution surface elevation changes from a multimission synthesis of radar and laser satellite altimeters, net mass changes can be effectively downscaled (within a Bayesian framework) to less than 20 km (~12 mi) resolution, which is sufficiently high resolution to resolve individual ice streams in Antarctica that cannot be separated using G/G-FO data alone.

NGGM and Bridging the Gap 

The presenters in this session provided status-update on the GRACE-C mission, a joint project between NASA and the Deutsches Zentrum für Luft- und Raumfahrt (DLR) [German Aerospace Center], as well as on future instrument developments and mission concepts. 

The 2017 NASA Earth Science Decadal Survey Report highlighted mass-transport monitoring through gravity change as one of five designated observables (i.e., top priorities for study) in Earth observations for the next decade in collaboration with international partners. The GRACE-C project successfully passed the NASA/JPL Mission Concept Review in June 2022, and the NASA Key Decision Point B review in September 2023 and is currently in its Phase B project definition phase. GRACE-C will be a single satellite pair based on a fully redundant LRI (as demonstrated on GRACE-FO) in a polar orbit at 500 km (~311 mi) altitude. To avoid a data gap after GFO, a launch date of no later than 2028 is targeted for GRACE-C.

Similarly, GFZ has been conducting model simulation studies to determine the value of adding a second satellite pair, dubbed Next-Generation Gravity Mission (NGGM) in Europe.  The experiments reveal that advanced parameterization techniques for improved de-aliasing of short-term mass variations can significantly reduce data errors and open the possibility for higher spatial and temporal resolution data products and science applications.

The technology demonstration LRI on G-FO has surpassed its performance requirements. With a LRI expected to be the primary instrument for the GRACE-C mission as well as other future GRACE-like missions, development of a new technique is required to provide long-term laser frequency knowledge to provide a scale correction factor to the geodesy measurement. The LRI-team presented updated results of a so-called scale factor measurement technique that allows the accurate determination of the laser frequency on-orbit that can meet the stringent GRACE-C mission requirements. This was achieved with a dual frequency modulation scheme, and a prototype electronics unit has been developed and tested, demonstrating performance better than the expected mission requirements. 

There were also reports on progress in technology development of low-frequency optomechanical accelerometers for geodetic applications. These highly-sensitive, compact, portable – and cost-effective – optomechanical inertial sensors build upon recent advances in optomechanics to measure accelerations with small form factors. The development of a sensor with lower cost, size, weight, and power – yet with GRACE-like performance – is a major achievement as these could be integrated into cost-effective mission designs, spacecraft miniaturization, simplified architectures, as well as for the deployment of constellations of satellite pairs flying at lower altitudes.

Section B: Geophysics and Climate Science

There were five sessions included in this section of the agenda, which are summarized in the subsections below as follows: Hydrology (Session B4), Cryosphere (Session B2), Solid Earth Sciences (Session B1), Oceanography (Session B3), and Multidisciplinary Science (Session B5). 

Hydrology 

This session, with 12 presentations, highlighted advances in hydrology research and applications using G/G-FO data enabled by the unique value of long, uninterrupted mass change climate data record. 

The topic of terrestrial water storage variations in California came up in several presentations, focusing on the see-saw swings between very wet and very dry years and the early impacts on groundwater recharge after the record-breaking snow accumulation during the 2022/2023 winter. The process of groundwater recharge – an important objective in the 2017 Earth Science Decadal Survey – is not well understood because of the challenges in observing infiltration of new water supply into the ground and the effects of rate of input, amount of input, and various aquifer characteristics. By combining observations of precipitation, snow water equivalent, surface water storage, ground surface deformation, and groundwater storage from G/G-FO, recharge behavior can be characterized in a natural experiment where source inputs are effectively not limited, but recharge capacity is limited. Results of studies shown during the meeting reveal that only a fraction of total available potential recharge can enter the aquifer, and that G/G-FO observations allow us to measure the effective aggregated recharge capacity and how it varies with several predictors. Another paper reported that subsurface water increases in California’s Sierra Nevada by 0.6 m (~2 ft) from October 2022 to June 2023, which represents 43% of the cumulative precipitation. 

Several presenters reported on efforts to advance concepts to downscale G/G-FO data to bring the information closer to decision-making scales and expand water-related applications, as well as to fill gaps and expand the data record with multisensor observations. One presenter described a new spectral approach that employs wavelet multiresolution analysis to combine seasonal terrestrial water storage change data from G/G-FO with those from global navigation satellite system (GNSS) ground station networks to downscale the observations to smaller hydrological basins and to better separate processes over complex topographical terrain. This method can also be used by fusing G/G-FO and hydrological model data [e.g., from NASA’s Global Land Data Assimilation System (GLDAS) models at continental scales]. Importantly, the method yields trends and long-term signals that match G/G-FO observations – a strength of the observing system. Another approach used a statistical Bayesian framework to incorporate G/G-FO observations and Soil Moisture Change data from different available sources [e.g., NASA’s Soil Moisture Active Passive (SMAP) mission] to obtain nonparametric likelihood functions that allow for downscaling. A statistical technique called cyclostationary empirical orthogonal function (CSEOF) analysis – which is used to interpret space-time variability in a large dataset – allowed researchers to fill short data gaps (~1 year) in G/G-FO record (e.g., between 2017 and 2018 – the gap between GRACE and GRACE–FO) without having any additional data. With the support of physically-related data (e.g., precipitation and temperature), CSEOFs can be used to reconstruct water changes into the past or fill larger data gaps. Such datasets improve understanding of trends and natural variability and anticipate future trends in response to climatic changes. 

Another presenter described a science study that found an apparent abrupt decline in temperate (non-ice) Terrestrial Water Storage (TWS) in 2015 to a new, lower regime that appears to be unique in the past 33 years. The triggering event for this new lower TWS regime appears to be the massive drought in Brazil in 2015. Subsequent droughts around the world (e.g., Europe, the western U.S., Canada, central Africa, and southern Brazil) have helped to keep TWS values depressed. Warm global sea surface temperatures, prevalent since 2015, have decreased rain accumulation over the continents, reducing TWS.

In the European Alps region, a G/G-FO data analysis found that glacier and ice changes are the major contributors to the observed signals. Overall, glaciers here have lost ice mass at rates between 1.4 to 2.2 Gt/year since 2002. Advances in spatial downscaling and data combinations are expected to allow for improved estimates and applications, including geological hazard monitoring.

In Northern Italy, accelerated groundwater loss has been detected using G/G-FO, well measurements, and vertical land motion observations. Since 2015, the groundwater loss has accelerated. Assuming a best-case scenario (conditions similar to 2007–2014), it could take 13–28 years for ground water storage to recover from recent long-term period of decline, thus setting the stage for prolonged drought conditions.

Since a pioneering study in 2014, it is well-established that G/G-FO observations of TWS are an effective means to estimate flood potential and flood risks due to water-saturated soil. Novel G/G-FO data processing schemes that exploit sub-monthly variations of total water storage enabled researchers to delineate basin-specific storage-discharge dynamics more accurately. They found that at submonthly timescales in many global basins, water storage (i.e., saturated soil) has more impact on whether a flood will occur than the amount of precipitation that falls. 

Along the Nile River, G/G-FO data were used to monitor water changes in crucial artificial reservoirs. These data indicate that water losses through underground-seepage over the geologically highly fractured region via a complex network of shear systems, faults, and fractures, are significant and could impact the delicate water balance in the region. A separate study focusing on nearby Southern Arabia found that intense tropical cyclones (wind speeds > 64 kph or ~40 mph) have doubled in the past decade compared to the preceding two, which resulted in significant recharge of the aquifers in the study area. The findings demonstrate the ability of G/G-FO to capture recharge signals and monitor aquifer systems in poorly gauged basins and highlight the significant role of tropical cyclones in recharging aquifers in arid Arabia.

Cryosphere

The five contributions in this session reported on new ice mass balance results of the Earth’s land-ice, as well as on novel data-combinations approaches that can improve the spatial resolution over G/G-FO-only data.

The Antarctica Ice Sheet contributes to the largest sea level rise potential and remains as the largest uncertainty source in the prediction of future sea levels. Data from G-FO and the Ice, Clouds and land Elevation Satellite–2 (ICESat-2) mission have been used to track ice sheet mass and height changes in Greenland and Antarctica, respectively. By combining the strengths of G-FO (gravity or mass change) and ICESat-2, (laser altimetry) data, a more accurate and less uncertain estimate of ice sheet mass changes can be achieved. This combination has led to a proposal for an enhanced iterative algorithm for deriving Antarctic mass balance, incorporating key technologies such as altimetry, gravity measurements, Global Positioning System (GPS) satellite data, and surface mass balance models. The study utilizes an effective density map derived from ICESat-2 and tests the algorithm’s sensitivity and uncertainty with synthetic data, considering realistic physical processes and variability. This approach aims to address discrepancies in estimating ice mass loss in East Antarctica and provides important guidance for optimizing future ground measurements (i.e., GPS station positions). Another presentation focused on understanding the differences in mass change recovered by the G/G-FO and IceSat-2 missions – both in terms of spatial distributions and total magnitudes – to ultimately determine a best combined estimate of ice sheet mass change leveraging the strengths of each mission. 

Temporal gravity field estimates from G/G-FO data reveal that the Antarctic ice sheet contributed approximately 6.1 mm (~0.2 in) to global sea level rise from 2002–2022, with a net loss of ~2150 GT of mass. While mass change accelerated during the GRACE era, it has decelerated during the GRACE-FO era – due to increased mass gain in East Antarctica. The deceleration is attributed to surface mass balance processes: annual precipitation and increased incidences of extreme weather events in East Antarctica, challenging predictions based on correlations with climate indices like Southern Annular Mode and El Niño Southern Oscillation.

A related study confirmed a pause in Antarctica’s mass loss, a non-accelerating mass loss in Greenland, and a steady loss from glaciers and ice caps away from the poles. The use of the LRI observations enabled novel submonthly analysis in key regions (including the Amundsen Sea Embayment of West Antarctica and the Pine Island/Thwaites basins) to gain more understanding of fast ice dynamics and their spatial extent.

While G/G-FO data span two decades, estimates of Earth’s oblateness from other satellite observations that date back to 1976 and provide a much longer data record – albeit at much coarser spatial resolution. This half-century long timeseries provides important constraints on ice mass change prior to the launch of GRACE in 2002. The data suggest that ice mass loss had already begun to accelerate by the 1990s. Recent progress in Earth system models, in conjunction with the long satellite data record, are being used to isolate trends in glacial isostatic adjustment (GIA) – which is the vertical movement of the Earth’s surface after the weight of glaciers is removed from them – and to improved estimates of ice mass loss prior to GRACE.

Solid Earth Sciences

Two presenters in this session described their efforts to evaluate signals in the G/G-FO data record associated with earthquakes. The G/G-FO data provide a unique opportunity to observe the Earth’s response to great earthquakes across diverse tectonic settings at time scales from days to decades. Using 13 earthquakes of magnitude (Mw)>8.0 over the last 20 years, it was found that elastic bulk modulus and viscosity govern large-scale coseismic and postseismic gravimetric changes, respectively. By constraining the solid Earth’s viscosity structure, improved physics-based models of long-term postseismic changes can be developed that incorporate observations from G/G-FO. The portion of the long-term gravity change signal that can be attributed to these earthquakes can then be removed from the G/G-FO data to better quantify processes related to ocean mass and hydrology changes. When physics-based models are not available, alternative statistic-based approaches can be used to remove the co- and post-seismic signature of large earthquakes (e.g., 2004 Andaman-Sumatra and 2011 Tohoku, Japan quakes) from the G/G-FO data. 

As the G/G-FO data record extends into its third decade, the long time series of Earth gravity changes requires careful consideration of the solid-Earth response to contemporary surface mass changes. To isolate the gravity signature of any surface mass signal, it is becoming evident that simple elastic loading corrections are no longer sufficient. Recent advances in mantle rheology – describing and understanding the nature of Earth’s mantle – derived in mineral laboratory experiments, tidal modeling, and seismic imaging provide unequivocal evidence of anelastic contributions to solid-Earth deformation on time-scales ranging from hours to decades. New developments in the solid-Earth capabilities of JPL’s Ice-sheet and Sea-level System Model (ISSM) in the form of viscoelastic solvers for Love numbers and sea-level change was used to implement and explore the so-called Extended Burgers Material (EBM) and so resulting viscoelastic deformations between the seismic and GIA time scales. Preliminary testing with EBM rheology shows potential for a ~15–20% increase in mass change trends for some regions.

A subdecadal variation of large-scale (i.e., spanning over continental scales) gravity signals with a period of approximately six years has attracted intense interest in the geodesy and geodynamic communities. Earth’s fluid core motions, magnetic field, Earth rotation, and crustal deformations have been invoked as causes for this signal. An analysis of G/G-FO data showed that a significant part of the approximately six-year signals is in fact due to climate-related oscillation of ocean-atmosphere coupling in the Pacific and Atlantic and variations in the land water storage over Africa.

Oceanography

In the oceanography session, five presenters reported on the combination of G/G-FO, satellite altimeters (e.g., from the joint NASA–European Sentinel-6 Michael Freilich mission), and in situ ocean floats (e.g., Argo) to investigate variations in sea level and ocean circulations – e.g., see Figure 1. Other presenters discussed improvements in data processing by reducing errors in atmospheric tides that could lead to spurious trends or double-counting a subset of ocean tides and by incorporating new dedicated ocean data grids that remove geodetic signals not related to ocean dynamics (e.g., global ocean mass; large earthquake signals).

Another presenter described how ocean mass redistribution and regional sea-level rise in the North-West Pacific marginal seas (i.e., around Japan and north of the Philippines) is impacted by seafloor deformation from earthquakes, which alter the ocean bathymetry. G/G-FO data are key to isolating these deformation effects, which in turn allows better sea level projections that can be used for planning purposes.

While long-term sea level trends are of major concern, the seasonal cycle is the dominating climate signal in ocean bottom pressure variability. Accurate representation of seasonal cycle is thus key to efforts to improve observations and models of ocean bottom pressure. Examining differences between models and observations elucidates remaining uncertainty in observations and missing physics in the models (e.g., lack of intrinsic variability due to coarse resolution, no accounting of gravitational and loading effects). This allows researchers to advance the quality of ocean mass change observations and unravel underlying dynamics.

Lastly, ocean bottom pressure observations from G/G-FO have been used to monitor transport variability of deep currents associated overturning circulation in the Northern Hemisphere (the Labrador Current) and Southern Hemisphere (Weddell Sea Bottom Water). This deepwater transport provides an important pathway for the sequestration of excess atmospheric heat and carbon from locations of water mass formation. Continuous observations of deep ocean currents provide valuable insight into Earth’s climate system. However, harsh conditions and complex recirculation transport pathways make in-situ observations of these deep flowing currents challenging.

Interdisciplinary Science

Six presenters contributed to this session. The first study revisited geodetic assumptions about measuring so-called Earth Center-of-Mass (CM) motions that can be traced to planetary-scale seasonal and long-term variations of water cycling between the land the oceans. Differences in SLR and G/G-FO estimates of CM estimates can be helpful to refining global circulation models. In a related study, G/G-FO and SLR data have been used to pin down the causes and origin of polar motion, particularly the mass component related to gravity changes. A novel hybrid SLR/GRACE time-variable gravity approach closely aligned well with the hydrological excitation in independently polar motion.

Errors in GIA corrections impact altimeter estimates of sea level and ocean mass estimates and the so-called sea level budget. Choices in modeling GIA, particularly based on paleoshoreline sites, affect Earth’s viscosity structure and GIA response, influencing global mean sea level (GMSL) budget closure. Even minor Earth model changes can have notable effects on the alignment of GMSL (altimetry), ocean mass (GRACE), and steric sea level change (Argo). Thus, future research needs to focus on accounting for the complex three-dimensional structure of the solid Earth to improve GIA corrections and more accurately isolate contemporary mass change in the G/G-FO data record.

Despite GIA uncertainties, G/G-FO, in combination with sea level measurements from altimetry, provide a unique capability to measure changes in ocean heat content. The ocean takes up nearly 90% of Earth’s current energy imbalance, signifying their important role in overall planetary heating. Two presenters reported consistent findings of ocean heat uptake rates of 0.9 W/m² based on the indirect geodetic satellite measurements of sea level and ocean mass – a value that is entirely independent of other techniques and thus provides crucial validation – see Figure 2. In addition, the results indicated the overall heating rate over the last decade has increased, which means heat accumulation is accelerating.

Summary

The hybrid 2023 G-FO STM brought together over 120 international participants and showcased a broad range of science results and applications that are supported and uniquely enabled by the satellite gravimetry-based mass change observations. The G-FO data now span nearly six years and continue to provide crucial insights into how Earth’s hydrosphere, including sea level, ocean currents, and water distribution over land, is changing. The G/G-FO data are extending important climate data records (e.g., the Greenland and Antarctic ice mass time-series, ocean mass sea level data, and TWS over land) into their third decade. The upcoming GRACE-C mission will build on and expand this mature data record, which is increasingly enabling important applications in support of water-related decision making and planning.

The G-FO project team remains focused on providing the mass-change data record at a level of performance consistent with that of GRACE. As the current Solar Cycle 25 increases towards its anticipated maximum in 2024, the team continues to improve the mission’s accelerometer data products in support of that goal. Corresponding data improvements in the monthly gravity and mass change products will be released early 2024.

The next G-FO STM will be held from October 8–10, 2024 in Potsdam, Germany, organized by GFZ. Check the GRACE website for specific details as the date gets closer.

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Spaceflight effects tumor-bearing fruit fly hosts and their parasites

How does spaceflight affect tumor-bearing fruit fly hosts and their parasites?

Background: Like humans, fruit flies (a model organism for spaceflight research) also exhibit immune system dysfunction in space. Despite decades of studies on fruit flies and wasps, little was known about how their immune systems interact with natural parasites in space. Drosophila parasitoid wasps modify blood cell function to suppress host immunity. In this spaceflight study (the Fruit Fly-03 Lab flown to the ISS on SpaceX-14), naive and parasitized ground and space flies from a tumor-free control and a blood tumor-bearing mutant strain were examined.

Main Findings: Surprisingly, the flies without tumors were more sensitive to space than the flies with tumors. Spaceflight increased immune gene activity and made tumors grow more in the flies. The wasps remained harmful in space, but some developed inheritable physical changes. These changes included “aurum” (altered wing color and veins) and “kona” (altered wing shape). Female wasps with two copies of the “kona” mutation could not lay eggs because of defective egg-laying organs.

Impact: This study will Improve our knowledge of how parasites and hosts interact. The results show that we need to study more types of organisms, including plants and their natural parasites, in space. This will help us learn more about how hosts defend themselves and how dangerous parasites can be in space, which is important for astronaut health. Gene expression data from fruit flies (OSD-588) and two types of wasps (OSD-609 & OSD-610) are publicly available on NASA’s Open Science Data Repository. This data is available for anyone to use and compare with other spaceflight studies.

Reference: Chou, J., Ramroop, J.,  Saravia-Butler, A., Wey, B., Lera, M., Torres, M., Heavner, M., Iyer, J., Mhatre, S,. Bhattacharya, S., Govind, S. Drosophila parasitoids go to space: Unexpected effects of spaceflight on hosts and their parasitoids. iScience, Volume 27, Issue 1, 2024, 108759, ISSN 2589-0042, https://doi.org/10.1016/j.isci.2023.108759

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Elizabeth E. Keller

The Marshall Star for May 29, 2024

More to Marshall: Center Leadership Provides Updates During Spring All-Hands Meeting

By Wayne Smith

NASA’s Marshall Space Flight Center will celebrate its 65th birthday next summer, and while there are plans to honor the center’s rich history, there is also More to Marshall ahead.

That was part of the message Center Director Joseph Pelfrey delivered during the spring all-hands meeting May 20 in Activities Building 4316. He highlighted Marshall’s transformative shift to more strategic partnerships across NASA and with industry, with the center continuing to serve as a technical solutions provider.

“More to Marshall is a systematic approach that will reinforce our center’s strategy and our role in space exploration,” Pelfrey said. “We align this vision with the core values of our Marshall fabric. We are not replacing our roots; we are fostering them to grow stronger and reach farther.”

Pelfrey also discussed the center’s evolving culture, highlighting April outreach activities, including the Total Solar Eclipse event in Russellville, Arkansas, First Robotics, Student Launch, and the Human Exploration Rover Challenge.

“These events emulate the Marshall culture,” Pelfrey said. “I am proud of the impact you have on the community, the Artemis Generation, and across the globe.”

New Deputy Director Rae Ann Meyer followed Pelfrey’s opening remarks, focusing on the center’s newest culture initiatives. Meyer also invited Trace Turner, management assistant in the Office of the Director, to highlight the efforts of three Center Action Teams leading the charge on Marshall’s culture initiatives. Team leaders Rocio Garcia, Benjamin Ferrell, and Mason Quick each shared more about their respective team’s projects, including the development of a user-friendly app that will share information on Marshall, NASA’s Michoud Assembly Facility, Redstone Arsenal, and the community.

Larry Leopard, Marshall’s associate director, technical, provided an update on the center’s efforts to address knowledge management concerns, starting with events like Meals with Mentors, Center Strategy Brown Bags and Tech Talk presentations, and after-action reviews.

Finally, before Marshall leadership participated in a question-and-answer panel, Pelfrey shared updates on center strategy, infrastructure, NASA’s budget, and NASA 2040.

“We will build on the success of our center strategy,” Pelfrey said. “We will continue to implement and mature our pursuits culture, always seeking challenging and exciting opportunities, using our skills, expertise, capabilities, and infrastructure while continuing to build partnerships with industry and academia. Marshall has a tremendous role in returning humans to the Moon, reaching Mars, and exploring the cosmos.”

Team members can watch a recording of the all-hands meeting on Inside Marshall.

Smith, a Media Fusion employee and the Marshall Star editor, supports the Marshall Office of Communications.

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Les Johnson Named Center Chief Technologist at Marshall

Les Johnson has been named center chief technologist at NASA’s Marshall Space Flight Center, effective June 2.

Johnson will provide expert advice on technology initiatives to center leadership and to Marshall team members. He will lead the Marshall team on matters involving center-wide technology development. Johnson also will represent Marshall on NASA’s Center Technology Council and serves as the center’s focal point for Center Innovation Fund activities.

He has been a principal technologist for several of NASA’s advanced in-propulsion and power technology developments during his 33-year career at Marshall. Johnson served as the principal investigator of the Propulsive Small Expendable Deployer System (ProSEDS) tether propulsion project and Near-Earth Asteroid Scout solar sail mission. He was a co-investigator (Co-I) of the JAXA T-Rex tether propulsion demonstration, the European Union’s InflateSail, and NASA’s Lightweight Integrated Solar Array and anTenna (LISA-T) missions, as well as a Co-I on multiple NASA Innovative Advanced Concepts (NIAC) studies.

Johnson began his NASA career in 1990 working in the Program Development Directorate formulating new space science mission concepts. Shortly thereafter, he became the manager for NASA’s Interstellar Propulsion Technology Project that transitioned into the In-Space Propulsion Technology Program, which he managed on behalf of the Office of Space Science. He then served as the formulation manager for the Nuclear Systems Initiative, which became Project JIMO. Johnson served as deputy manager and technical assistant for the Advanced Concepts Office, before being selected to lead the development of the Solar Cruiser solar sail propulsion system in the Science and Technology Office.

Prior to NASA, he worked three years for General Research Corp. on directed energy systems in support of the Strategic Defense Initiative.

Johnson holds three patents. His awards include NASA’s Exceptional Technology Achievement Medal, NASA’s Exceptional Achievement Medal (twice), Marshall’s Technology Transfer and Innovation Awards, and he has been a Rotary Stellar Award finalist two times. As an outside activity, he is also an award-winning author.

A native of Ashland, Kentucky, Johnson earned his bachelor’s degree from Transylvania University and his master’s degree from Vanderbilt University.

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Take 5 with Jose Matienzo

By Wayne Smith

Growing up in the small village of Luquillo, Puerto Rico, Jose Matienzo would fly paper airplanes and launch model rockets from atop the building he lived in with his family.

“I knew then that I wanted to be some sort of engineer, I just didn’t know what it was called,” Matienzo said. “I never imagined that I actually would work for NASA, but I thought I could design cars or planes. I liked drawing them.”

Flash forward more than five decades later. Matienzo is in his 42nd year working with NASA and the agency’s Marshall Space Flight Center as he nears retirement in December. Center team members will remember him as manager of the Marshall Exchange for the past 12 years, enjoying his witty daily email from the Exchange.

“Literally every day was fun trying to make life better for our team members,” Matienzo said of his team with the Exchange. “That includes bringing the food truck court, being able to have employee clothing of all styles and types, creating new clubs, and expanding facilities.”

He is currently assigned to a position with NASA’s Source Evaluation Board.

As he approaches retirement, Matienzo still finds it difficult to fathom his many milestones working with NASA and Marshall, where he began his career in 1983 as a co-op student in the structural dynamics division and worked on the Space Shuttle Program for 12 years. Matienzo followed that with a year at NASA Headquarters before returning to Marshall as lead engineer on several projects related to the International Space Station, such as the space station element transportation system.

His other assignments have included managing the NASA office at the Naval Research Center; the Marshall lead for supporting the Launch Services Program, including the office at the United Launch Alliance rocket plant in Decatur; technical assistant for former Marshall Director Robert Lightfoot; and more. 

“There have been so many memories over the years,” Matienzo said. “Six months after becoming a full-time employee, the Challenger accident happened. At the time I had no idea what the possible impact of that accident would be. We all had a little part on returning to flight, so watching the first launch afterwards was a fantastic moment.

“We delivered space station hardware in partnership with the Italians and the European Space Agency, helped train the astronauts who performed the Hubble Telescope repair, and most recently, we made improvements to the Exchange services to make life at work better for our employees.”

Question: What excites you most about the future of human space exploration, or your NASA work, and your team’s role it?

Matienzo: I’ve been here for a long time and our future missions and goals have changed over the years. But no matter what, there’s always been excitement about meeting the agency’s goals and Marshall’s role in providing space transportation, lunar landers, and even Mars sample return vehicles. That and all of the support and testing work that comes with it is fun! 

Question: Who or what drives/motivates you?

Matienzo: I’ve been lucky that my job assignments have always been fun and self-motivating, but certainly dealing and coordinating with colleagues in accomplishing a mutual goal, test, or assignment is very rewarding.

Question: What advice do you have for employees early in their NASA career or those in new leadership roles?

Matienzo: Network! As you get to know others and learn what they do, you will find out how everything comes together at NASA and where other opportunities may be out there for you. For our leaders: keep encouraging, mentoring, and creating opportunities for the employees to experience, learn, and grow.

Question: What do you enjoy doing with your time while away from work?

Matienzo: My kids are older now so keeping in touch is fun. But I do have grandkids to play with. Otherwise, I play congas with my bandmates, love to do social dancing, play lots of pickleball, and enjoy mountain and road bike riding.

Question: What plans do you have for retirement?

Matienzo: I want to move closer to the beach. I love Huntsville, so I want to keep a presence here. I also plan to bike all over the USA!

Smith, a Media Fusion employee and the Marshall Star editor, supports the Marshall Office of Communications.

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Marshall Team Supports Safe Travels for Space Station Science

By Jessica Barnett 

During the International Space Station’s more than 25 years of operation, there have been more than 3,000 experiments conducted aboard the microgravity laboratory, and making sure scientific samples are kept safe through launch, spaceflight, experimentation, and the return trip to Earth takes a great deal of planning, testing, and preparation across NASA.

In February, team members at NASA’s Marshall Space Flight Center handled the de-integration of zinc selenide-based crystals grown on the space station as part of an experiment to study how a lack of gravity might affect the crystals’ growth and structure. The experiment was conducted using six sample cartridge assemblies heated up to 1,200 degrees Celsius (2,192 degrees Fahrenheit) inside the Materials Science Laboratory of the Materials Science Research Rack on the space station.

John Luke Bili, lead systems test engineer for the sample cartridge assemblies within Marshall’s Instrument Development, Integration, and Test Branch, begins the process by working with engineers, scientists, project personnel, and the experiment’s principal investigator to create an ampoule, or sealed glass vial, to use as a sample container.

“We’ll take the ampoule and do some ground testing, like a normal flight integration,” Bili said. “We’ll assemble it with the hardware we have, then we are responsible for completing different mitigation efforts to prepare for sealing the ampoule up and processing it at the required high temperatures.”

The team exposes the test article to extreme heat and pressure using a duplicate of the furnace on the space station, allowing them to also test the experiment’s software.

The zinc selenide-based crystal experiment required six sample cartridge assemblies. After a month of preparation from Marshall’s team, the assemblies traveled to NASA’s Johnson Space Center for a final round of packing before arriving at the agency’s Kennedy Space Center for launch.

The assemblies launched on NASA’s SpaceX 24th commercial resupply services mission in December 2021 and NASA’s Northrop Grumman 19th commercial resupply services mission in August 2023. Each sample took about a week to process through the space station’s lab furnace. The samples were then brought back to Earth, with three of the six arriving at Marshall on Feb. 9.

While unpacking the crystal samples, team members took photos and notes of the tubes throughout the de-integration process in Marshall’s Space Systems Integration & Test Facility. The team includes technicians with 20 to 30 years of experience, ensuring samples safely travel to and from the station and helping expand access for researchers to explore microgravity, space exposure, and future missions in low Earth orbit.

“It’s really nice having that kind of experience when we’re working on the hardware that’s going in space,” he said. “We’ve got a lot of people that are very skilled machinists that are able to help us in a moment’s notice, we have people with a really good understanding of technical tolerances and stuff like that, and we have people with a lot of varying experience doing flight hardware integration and tests.”

For more than two decades, humans have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and making research breakthroughs that are not possible on Earth. The station is a critical testbed for NASA to understand and overcome the challenges of long-duration spaceflight and to expand commercial opportunities in low Earth orbit.

Learn more about the space station.

Barnett, a Media Fusion employee, supports the Marshall Office of Communications.

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Spotted: ‘Death Star’ Black Holes in Action

A team of astronomers have studied 16 supermassive black holes that are firing powerful beams into space, to track where these beams, or jets, are pointing now and where they were aimed in the past, as reported in a press release. Using NASA’s Chandra X-ray Observatory and the U.S. National Science Foundation (NSF) National Radio Astronomical Observatory’s (NRAO) Very Large Baseline Array (VLBA), they found that some of the beams have changed directions by large amounts.

These two Chandra images show hot gas in the middle of the galaxy cluster Abell 478 (left) and the galaxy group NGC 5044 (right). The center of each image contains one of the sixteen black holes firing beams outwards. Each black hole is in the center of a galaxy embedded in the hot gas.

In the images below, labels and the radio images appear. Ellipses show a pair of cavities in the hot gas for Abell 478, left, and ellipses show two pairs of cavities for NGC 5044, right. These cavities were carved out by the beams millions of years ago, giving the directions of the beams in the past. An X shows the location of each supermassive black hole.

The VLBA images are shown as insets, which reveal where the beams are currently pointing, as seen from Earth. The radio images are both much smaller than the X-ray images. For Abell 478 the radio image is about 3% of the width of the Chandra image and for NGC 5044 the radio image is about 4% of the Chandra image’s width.

A comparison between the Chandra and VLBA images shows that the beams for Abell 478 changed direction by about 35 degrees and the beams for NGC 5044 changed direction by about 70 degrees.

Across the entire sample the researchers found that about a third of the 16 galaxies have beams that are pointing in completely different directions than they were before. Some have changed directions by nearly 90 degrees in some cases, and over timescales between one million years and a few tens of millions of years. Given that the black holes are of the order of 10 billion years old, this represents a relatively rapid change for these galaxies.

Black holes generate beams when material falls onto them via a spinning disk of matter and some of it then gets redirected outward. The direction of the beams from each of these giant black holes, which are likely spinning, is thought to align with the rotation axis of the black hole, meaning that the beams point along a line connecting the poles.

These beams are thought to be perpendicular to the disk. If material falls towards the black holes at a different angle that is not parallel to the disk, it could affect the direction of the black hole’s rotation axes, changing the direction of the beams.

Scientists think that beams from black holes and the cavities they carve out play an important role in how many stars form in their galaxies. The beams pump energy into the hot gas in and around the galaxy, preventing it from cooling down enough to form huge numbers of new stars. If the beams change directions by large amounts, they can tamp down star formation across much larger areas of the galaxy.

The paper describing these results was published in the January 20th, 2024 issue of The Astrophysical Journal, and is available here. The authors are Francesco Ubertosi (University of Bologna in Italy), Gerritt Schellenberger (Center for Astrophysics | Harvard & Smithsonian), Ewan O’Sullivan (CfA), Jan Vrtilek (CfA), Simona Giacintucci (Naval Research Laboratory), Laurence David (CfA), William Forman (CfA), Myriam Gitti (University of Bologna), Tiziana Venturi (National Institute of Astrophysics—Institute of Radio Astronomy in Italy), Christine Jones (CfA), and Fabrizio Brighenti (University of Bologna).

NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science from Cambridge Massachusetts and flight operations from Burlington, Massachusetts.

Read more from NASA’s Chandra X-ray Observatory.

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NASA, IBM Research to Release New AI Model for Weather, Climate

By Jessica Barnett

Working together, NASA and IBM Research have developed a new artificial intelligence model to support a variety of weather and climate applications. The new model – known as the Prithvi-weather-climate foundational model – uses artificial intelligence (AI) in ways that could vastly improve the resolution we’ll be able to get, opening the door to better regional and local weather and climate models.  

Foundational models are large-scale, base models which are trained on large, unlabeled datasets and can be fine-tuned for a variety of applications. The Prithvi-weather-climate model is trained on a broad set of data – in this case NASA data from NASA’s Modern-Era Retrospective analysis for Research and Applications (MERRA-2)– and then makes use of AI learning abilities to apply patterns gleaned from the initial data across a broad range of additional scenarios.  

“Advancing NASA’s Earth science for the benefit of humanity means delivering actionable science in ways that are useful to people, organizations, and communities. The rapid changes we’re witnessing on our home planet demand this strategy to meet the urgency of the moment,” said Karen St. Germain, director of the Earth Science Division of NASA’s Science Mission Directorate. “The NASA foundation model will help us produce a tool that people can use: weather, seasonal and climate projections to help inform decisions on how to prepare, respond and mitigate.”  

With the Prithvi-weather-climate model, researchers will be able to support many different climate applications that can be used throughout the science community. These applications include detecting and predicting severe weather patterns or natural disasters, creating targeted forecasts based on localized observations, improving spatial resolution on global climate simulations down to regional levels, and improving the representation of how physical processes are included in weather and climate models.

“These transformative AI models are reshaping data accessibility by significantly lowering the barrier of entry to using NASA’s scientific data,” said Kevin Murphy, NASA’s chief science data officer, Science Mission Directorate at NASA Headquarters. “Our open approach to sharing these models invites the global community to explore and harness the capabilities we’ve cultivated, ensuring that NASA’s investment enriches and benefits all.” 

Prithvi-weather-climate was developed through an open collaboration with IBM Research, Oak Ridge National Laboratory, and NASA, including the agency’s Interagency Implementation and Advanced Concepts Team (IMPACT) at NASA’s Marshall Space Flight Center. 

Prithvi-weather-climate can capture the complex dynamics of atmospheric physics even when there is missing information thanks to the flexibility of the model’s architecture. This foundational model for weather and climate can scale to both global and regional areas without compromising resolution. 

“This model is part of our overall strategy to develop a family of AI foundation models to support NASA’s science mission goals,” said Rahul Ramachandran, who leads IMPACT at Marshall. “These models will augment our capabilities to draw insights from our vast archives of Earth observations.”  

Prithvi-weather-climate is part of a larger model family– the Prithvi family – which includes models trained on NASA’s Harmonized LandSat and Sentinel-2 data. The latest model serves as an open collaboration in line with NASA’s open science principles to make all data accessible and usable by communities everywhere. It will be released later this year on Hugging Face, a machine learning and data science platform that helps users build, deploy, and train machine learning models. 

“The development of the NASA foundation model for weather and climate is an important step towards the democratization of NASA’s science and observation mission,” said Tsendgar Lee, program manager for NASA’s Research and Analysis Weather Focus Area, High-End Computing Program, and Data for Operation and Assessment. “We will continue developing new technology for climate scenario analysis and decision making.” 

Along with IMPACT and IBM Research, development of Prithvi-weather-climate featured significant contributions from NASA’s Office of the Chief Science Data Officer, NASA’s Global Modeling and Assimilation Office at Goddard Space Flight Center, Oak Ridge National Laboratory, the University of Alabama in Huntsville, Colorado State University, and Stanford University. 

Learn more about Earth data and previous Prithvi models.

Barnett, a Media Fusion employee, supports the Marshall Office of Communications.

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Psyche Fires Up Its Sci-Fi-Worthy Thrusters

NASA’s Psyche spacecraft passed its six-month checkup with a clean bill of health, and there’s no holding back now. Navigators are firing its futuristic-looking electric thrusters, which emit a blue glow, nearly nonstop as the orbiter zips farther into deep space.

The spacecraft launched from NASA’s Kennedy Space Center atop a SpaceX Falcon Heavy on Oct. 13, 2023. After leaving Earth’s atmosphere, Psyche made the most of its rocket boost and coasted beyond the orbit of Mars.

For the next year, the spacecraft will be in what mission planners call “full cruise” mode, when its electric thrusters take over and propel the orbiter toward the asteroid belt. The thrusters work by expelling charged atoms, or ions, of xenon, emitting a brilliant blue glow that trails behind the spacecraft.

They are part of Psyche’s incredibly efficient solar electric propulsion system, which is powered by sunlight. The thrust created by the ionized xenon is gentle, but it does the job. Even in full cruise mode, the pressure exerted by the thrusters is about what you’d feel holding three quarters in your hand.

The orbiter is now more than 190 million miles away and moving at a clip of 23 miles per second, relative to Earth. That’s about 84,000 mph. Over time, with no atmospheric drag to slow it down, Psyche will accelerate to speeds of up to 124,000 mph.

The spacecraft will arrive at the metal-rich asteroid Psyche in 2029 and will make observations from orbit for about two years. The data it collects will help scientists better understand the formation of rocky planets with metallic cores, including Earth. Scientists have evidence that the asteroid, which is about 173 miles across at its widest point, may be the partial core of a planetesimal, the building block of an early planet.  

The flight team used Psyche’s first 100 days in space to conduct a full checkout of all spacecraft systems. All of the engineering systems are working just as expected, and the three science instruments have been operating without a hitch. The magnetometer is working so well that it was able to detect an eruption of charged particles from the Sun, as did the gamma-ray and neutron spectrometer. And this past December, the twin cameras on the imaging instrument captured their first images.

“Until this point, we have been powering on and checking out the various pieces of equipment needed to complete the mission, and we can report they are working beautifully,” said Henry Stone, Psyche project manager at NASA’s Jet Propulsion Laboratory, which manages the mission. “Now we are on our way and looking forward to an upcoming close flyby of Mars.”

That’s because the spacecraft’s trajectory will bring it back toward the Red Planet in the spring of 2026. The spacecraft will power down the thrusters as it coasts toward Mars, using the planet’s gravity to slingshot itself out. From there, the thrusters return to full cruise mode. Next stop: the asteroid Psyche.

In the meantime, the Deep Space Optical Communications technology demonstration aboard the spacecraft will keep on testing its mettle. The experiment already surpassed expectations when, in April, it transmitted test data from over 140 million miles away at a rate of 267 megabits per second to a downlink station on Earth – a bit rate comparable to broadband internet download speeds.

Arizona State University leads the Psyche mission. A division of Caltech in Pasadena, JPL is responsible for the mission’s overall management, system engineering, integration and test, and mission operations. Maxar Technologies in Palo Alto, California, provided the high-power solar electric propulsion spacecraft chassis.

JPL manages DSOC for the Technology Demonstration Missions program within NASA’s Space Technology Mission Directorate and the Space Communications and Navigation program within the Space Operations Mission Directorate.

Psyche is the 14th mission selected as part of NASA’s Discovery Program, which is managed by the agency’s Marshall Space Flight Center. NASA’s Launch Services Program, based at Kennedy, managed the launch service.

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NASA’s OSIRIS-APEX Unscathed After Searing Pass of Sun

Mission engineers were confident NASA’s OSIRIS-APEX (Origins, Spectral Interpretation, Resource Identification – Apophis Explorer) spacecraft could weather its closest ever pass of the Sun on Jan. 2. Their models had predicted that, despite traveling 25 million miles closer to the heat of the Sun than it was originally designed to, OSIRIS-APEX and its components would remain safe.

The mission team confirmed that the spacecraft indeed had come out of the experience unscathed after downloading stored telemetry data in mid-March. The team also tested OSIRIS-APEX’s instruments in early April, once the spacecraft was far enough from the Sun to return to normal operations. Between December 2023 and March, OSIRIS-APEX was inactive, with only limited telemetry data available to the team on Earth.

The spacecraft’s clean bill of health was due to creative engineering. Engineers placed OSIRIS-APEX in a fixed orientation with respect to the Sun and repositioned one of its two solar arrays to shade the spacecraft’s most sensitive components during the pass.

The spacecraft is in an elliptical orbit around the Sun that brings it to a point closest to the Sun, called a perihelion, about every nine months. To get on a path that will allow it to meet up with its new target Apophis in 2029, the spacecraft’s trajectory includes several perihelions that are closer to the Sun than the spacecraft’s components were originally designed to withstand.

“It’s phenomenal how well our spacecraft configuration protected OSIRIS-APEX, so I’m really encouraged by this first close perihelion pass,” said Ron Mink, mission systems engineer for OSIRIS-APEX, based at NASA’s Goddard Space Flight Center.

Besides confirming that the January perihelion worked out according to predictions, engineers found surprises while testing spacecraft components. A couple of instruments came out better than expected after exposure to higher temperatures.

A camera that helped map asteroid Bennu and will do the same at Apophis, saw a 70% reduction in “hot pixels” since April 13, 2023, the last time it was tested. Hot pixels, which are common in well-used cameras in space, show up as white spots in images when detectors accumulate exposure to high-energy radiation, mostly from our Sun.

“We think the heat from the Sun reset the pixels through annealing,” said Amy Simon, OSIRIS-APEX project scientist, based at NASA Goddard. Annealing is a heat process that can restore function of instruments and is often done intentionally through built-in heaters on some spacecraft.

Another welcome surprise, said Simon, came from the spacecraft’s visible and near-infrared spectrometer. Before perihelion, the spectrometer, which mapped the surface composition of Bennu, and will do the same at Apophis, seemed to have a rock from Bennu stuck inside its calibration port. Scientist suspected that some sunlight was blocked from filtering through the instrument after the spacecraft, then called OSIRIS-REx, grabbed a sample from asteroid Bennu on Oct. 20, 2020. By picking up the sample and then firing its engines to back away from Bennu, the spacecraft stirred up dust and pebbles that clung to it.

“But, with enough spacecraft maneuvers and engine burns after sample collection,” Simon said, the rock in the calibration port appears to have been dislodged. Scientists will check the spectrometer again when OSIRIS-APEX swings by Earth on Sept. 25, 2025, for a gravitational boost.

OSIRIS-APEX is now operating normally as it continues its journey toward asteroid Apophis for a 2029 rendezvous. Its better-than-expected performance during the first close perihelion is welcome news. But engineers caution that it doesn’t mean it’s time to relax. OSIRIS-APEX needs to execute five more exceptionally close passes of the Sun – along with three Earth gravity assists – to get to its destination. It’s unclear how the cumulative effect of six perihelions at a closer distance than designed will impact the spacecraft and its components.

The second OSIRIS-APEX perihelion is scheduled for Sept. 1. The spacecraft will be 46.5 million miles away from the Sun, which is roughly half the distance between Earth and the Sun, and well inside the orbit of Venus.

OSIRIS-APEX (previously named OSIRIS-REx) is the third mission in NASA’s New Frontiers Program, managed by NASA’s Marshall Space Flight Center in for the agency’s Science Mission Directorate.

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Lee Mohon