25 Years Ago: Launch of Deep Space 1 Technology Demonstration Spacecraft
On Oct. 24, 1998, NASA launched the Deep Space 1 spacecraft. Managed by NASA’s Jet Propulsion Laboratory in Pasadena, California, Deep Space 1 served as a testbed for 12 new technologies, including solar electric, also known as ion propulsion, for use in future deep space and interplanetary missions. The spacecraft, the first in NASA’s New Millennium program, flew by asteroid Braille and comet Borrelly, returning images and scientific data about the two small bodies. The ion propulsion engine that Deep Space 1 successfully demonstrated allowed the Dawn spacecraft to explore the protoplanet Vesta and the dwarf planet Ceres using that technology. The Psyche spacecraft currently on its way to explore the asteroid of the same name, also uses ion propulsion. Future programs such as Gateway will use ion propulsion to enable human lunar exploration. Deep Space 1 completed its mission on Dec. 18, 2001.
Left: The fully assembled Deep Space 1 spacecraft prepared for launch. Middle: View of the Deep Space 1 spacecraft’s ion propulsion engine. Right: Launch of Deep Space 1 on a Delta II rocket from Launch Pad 17A at Cape Canaveral Air Force Station, now Cape Canaveral Space Force Station, in Florida.
The 12 technologies Deep Space 1 tested included the ion propulsion system; the autonomous navigation system; an autonomous control system; a beacon system that sends simple tones to Earth to advise controllers of spacecraft health; a solar array with concentrator lenses; an integrated camera and imaging spectrometer; an integrated ion and electron spectrometer; a small deep-space transponder; a Ka-band solid-state power amplifier; low-power electronics; a multifunctional structure testing new packaging technology; and a power activation and switching module. Scientists also gathered data on whether the ion engine’s plume interfered with any of the spacecraft’s instruments. The ion engine used xenon gas as its propellant and obtained power from the spacecraft’s high-efficiency solar arrays. Although providing low thrust overall, the engine achieved more thrust than any chemical engine.
The Deep Space 1 spacecraft’s primary mission trajectory, including the flyby of asteroid 1992 KD, renamed 9969 Braille.
The launch of Deep Space 1 took place atop a Delta II rocket on Oct. 24, 1998, from Launch Pad 17A at Cape Canaveral Air Force Station, now Cape Canaveral Space Force Station, in Florida. After entering an initial parking orbit around the Earth, the rocket’s third stage boosted Deep Space 1 into solar orbit. The initial mission plan included demonstration of the new technologies and a flyby of asteroid 1992 KD, renamed 9969 Braille shortly before the spacecraft’s encounter. On Nov. 10, ground controllers commanded the ion engine to commence firing but it only operated for 4.5 minutes. They tried again on Nov. 24 with the spacecraft 3 million miles from Earth, and this time the engine firing succeeded, running for the planned 14 days. Over the next six months, the spacecraft successfully tested all 12 of its technology demonstrations, completing the activity in June 1999.
Left: Illustration of Deep Space 1 and the blue exhaust of its ion propulsion engine. Middle: Blurry image of asteroid 9969 Braille. Right: Highest quality image of comet 19P/Borrelly.
Due to an onboard computer crash shortly before the encounter, as well as the inability of the autonomous navigation system to lock onto the darker than expected asteroid, Deep Space 1’s flyby of Braille on July 29, 1999, occurred at a distance of 16 miles instead of the planned 790 feet. Thus, the images the spacecraft returned did not show any detail, while other instruments provided good data. When the spacecraft’s primary mission ended on Sept. 18, 1999, mission managers approved an extended mission to target a flyby of comet 19P/Borrelly. The spacecraft’s star tracker failed on Nov. 11, 1999, putting the comet flyby in jeopardy. Over the next five months, ground controllers built a new attitude control system that did not rely on the star tracker, and the flyby could proceed. Deep Space 1 entered comet Borrelly’s coma on Sept. 22, 2001, and flew by its nucleus at a distance of 1,350 miles. The spacecraft provided the most detailed images of a comet’s nucleus up to that time. Having operated well beyond its expected lifetime and with its attitude control fuel running low, ground controllers turned off the spacecraft on Dec. 18, 2001. Its ion propulsion engine had operated for 16,265 hours, far longer than any previous spacecraft, and provided a total velocity change of three miles per second, the largest achieved by any spacecraft with its own propulsion system.
Left: Dawn spacecraft image of dwarf planet Ceres. Middle: Illustration of the Psyche spacecraft during its encounter with the asteroid of the same name. Right: Illustration of Gateway Habitation and Logistics Outpost and Power and Propulsion Element using ion propulsion.
The ion propulsion technology that Deep Space 1 demonstrated has found use in interplanetary uncrewed missions and will see use in future human lunar exploration. Launched in 2007, the Dawn spacecraft’s ion propulsion system enabled it to explore two worlds between 2011 and 2018, the protoplanet Vesta and the dwarf planet Ceres, entering orbit around each to conduct in-depth studies not otherwise possible. The Psyche spacecraft, currently on its way to explore the asteroid of the same name, also uses ion propulsion. In the arena of future human space exploration, the Gateway, part of NASA-led Artemis missions to return astronauts to the Moon, will establish a human presence in lunar orbit. The Gateway’s Power and Propulsion Element plans to use its Advanced Electric Propulsion System to arrive in lunar orbit and to maintain that orbit enabling regular astronaut visits.
How NASA Is Protecting Europa Clipper From Space Radiation
5 min read
How NASA Is Protecting Europa Clipper From Space Radiation
Engineers and technicians are seen closing the vault of NASA’s Europa Clipper in the main clean room of the Spacecraft Assembly Facility at JPL on Oct. 7. The vault will protect the electronics of the spacecraft as it orbits Jupiter.
NASA/JPL-Caltech
To explore the mysterious ice-encrusted moon Europa, the mission will need to endure bombardment by radiation and high-energy particles surrounding Jupiter.
When NASA’s Europa Clipper begins orbiting Jupiter to investigate whether its ice-encased moon, Europa, has conditions suitable for life, the spacecraft will pass repeatedly through one of the most punishing radiation environments in our solar system.
Hardening the spacecraft against potential damage from that radiation is no easy task. But on Oct. 7, the mission put the final piece of the spacecraft’s “armor” in place when it sealed the vault, a container specially designed to shield Europa Clipper’s sophisticated electronics. The probe is being put together, piece by piece, in the Spacecraft Assembly Facility at NASA’s Jet Propulsion Laboratory in Southern California ahead of its launch in October 2024.
Join team members from NASA’s Europa Clipper mission behind the scenes in a clean room at JPL to learn about the design of the spacecraft. Credit: NASA/JPL-Caltech
“Closing the vault is a major milestone,” said Kendra Short, Europa Clipper’s deputy flight system manager at JPL. “It means we’ve got everything in there that we have to have in there. We’re ready to button it up.”
Just under a half-inch (1 centimeter) thick, the aluminum vault houses the electronics for the spacecraft’s suite of science instruments. The alternative of shielding each set of electronic parts individually would add cost and weight to the spacecraft.
“The vault is designed to reduce the radiation environment to acceptable levels for most of the electronics,” said JPL’s Insoo Jun, the co-chair of the Europa Clipper Radiation Focus Group and an expert on space radiation.
Punishing Radiation
Jupiter’s gigantic magnetic field is 20,000 times as strong as Earth’s and spins rapidly in time with the planet’s 10-hour rotation period. This field captures and accelerates charged particles from Jupiter’s space environment to create powerful radiation belts. The radiation is a constant, physical presence – a kind of space weather – bombarding everything in its sphere of influence with damaging particles.
“Jupiter has the most intense radiation environment other than the Sun in the solar system,” Jun said. “The radiation environment is affecting every aspect of the mission.”
This illustration depicts NASA’s Europa Clipper as it flies by Jupiter’s moon Europa. The mission is targeting an October 2024 launch.
NASA/JPL-Caltech
That’s why when the spacecraft arrives at Jupiter in 2030, Europa Clipper won’t simply park in orbit around Europa. Instead, like some previous spacecraft that studied the Jovian system, it will make a wide-ranging orbit of Jupiter itself to move away from the planet and its harsh radiation as much as possible. During those looping orbits of the planet, the spacecraft will fly past Europa nearly 50 times to gather scientific data.
The radiation is so intense that scientists believe it modifies the surface of Europa, causing visible color changes, said Tom Nordheim, a planetary scientist at JPL who specializes in icy outer moons – Europa as well as Saturn’s Enceladus.
“Radiation on the surface of Europa is a major geologic modification process,” Nordheim said. “When you look at Europa – you know, the reddish-brown color – scientists have shown that this is consistent with radiation processing.”
Chaotic Icescape
So even as engineers work to keep radiation out of Europa Clipper, scientists like Nordheim and Jun hope to use the space probe to study it.
“With a dedicated radiation monitoring unit, and using opportunistic radiation data from its instruments, Europa Clipper will help reveal the unique and challenging radiation environment at Jupiter,” Jun said.
Nordheim zeroes in on Europa’s “chaos terrain,” areas where blocks of surface material appear to have broken apart, rotated, and moved into new positions, in many cases preserving preexisting linear fracture patterns.
Deep beneath the moon’s icy surface is a vast liquid-water ocean, scientists believe, that could offer a habitable environment for life. Some areas of Europa’s surface show evidence of material transport from the subsurface to the surface. “We need to understand the context of how radiation modified that material,” Nordheim said. “It can alter the chemical makeup of the material.”
The Power of Heat
Because Europa’s ocean is locked inside an envelope of ice, any possible life forms would not be able to rely directly on the Sun for energy, as plants do on Earth. Instead, they’d need an alternative energy source, such as heat or chemical energy. Radiation raining down on Europa’s surface could help provide such a source by creating oxidants, such as oxygen or hydrogen peroxide, as the radiation interacts with the surface ice layer.
Over time, these oxidants could be transported from the surface to the interior ocean. “The surface could be a window into the subsurface,” Nordheim said. A better understanding of such processes could provide a key to unlock more of the Jupiter system’s secrets, he added: “Radiation is one of the things that makes Europa so interesting. It’s part of the story.”
More About the Mission
Europa Clipper’s main science goal is to determine whether there are places below Jupiter’s icy moon, Europa, that could support life. The mission’s three main science objectives are to determine the thickness of the moon’s icy shell and its surface interactions with the ocean below, to investigate its composition, and to characterize its geology. The mission’s detailed exploration of Europa will help scientists better understand the astrobiological potential for habitable worlds beyond our planet.
IV&V Program’s Orion Team Receives Space Flight Awareness Award
FAIRMONT – The NASA Independent Verification & Validation Program’s Orion Team received an award for their contributions to the Artemis I Mission during a ceremony hosted at the I-79 Technology Park, in Fairmont.
The Goddard Space Flight Center (GSFC) Space Flight Awareness (SFA) Award Ceremony is an annual event recognizing employees and teams who have made strides in their role in promoting astronaut safety and mission success. Members of the IV&V Orion Team took home the team award for significant contributions “to improving the quality, reliability, and safety of the Orion Program’s safety and mission critical software in support of the Artemis I Mission.”
Members of the IV&V Orion Team pose for a celebratory photo with Astronaut and Scientist Stanley Love at the Space Flight Awareness Awards Ceremony, in Fairmont.
Travis Wohlrab GSFC
Artemis I was an uncrewed lunar flight test and the first in a series of increasingly complex missions that will enable human exploration at the Moon and future missions to Mars.
The IV&V winners were among those honored at a recent ceremony in Fairmont, West Virginia, with IV&V Program Director Wes Deadrick and NASA Astronaut and Scientist Stanley Love among those speaking at the event.
“It’s a treat to be able to come out and shake hands with some of the folks who keep us safe and keep our missions going,” Love said.
According to the SFA Program, the IV&V Orion Team identified and helped resolve nearly 3,000 high-severity issues and risks, working closely with its customers in the Orion Program and others.
According to the agency, on Artemis missions, Orion will carry the crew to space, provide emergency abort capability, sustain the crew during the space travel, and provide safe re-entry from deep space return velocities.
“NASA’s human spaceflight missions greatly rely on evolving systems and software, and if the safety for these systems fail then the mission fails,” Deadrick said during the ceremony. “In this regard, both for human spaceflight missions and for science missions, the IV&V Program has become indispensable to Goddard and the agency.”
IV&V Program Director Wes Deadrick makes a speech during the Space Flight Awareness Awards Ceremony, in Fairmont.
Observing Storms from the International Space Station
A storm is pictured in the Arabian Sea less than 700 miles off the coast of Oman as the International Space Station orbited 260 miles above.
NASA / Jasmin Moghbeli
While the International Space Station orbited 260 miles above Earth on Oct. 20, 2023, astronaut Jasmin Moghbeli snapped this image of a storm in the Arabian Sea, less than 700 miles off the coast of Oman. In addition to photographing our planet from the space station, NASA also observes Earth with satellites. These satellites collect data on storms that scientists can then use to create near real-time products to support disaster response.
For example, NASA and JAXA’s (Japan Aerospace Exploration Agency) Global Precipitation Measurement (GPM) satellite frequently observes the structure of precipitation within tropical cyclones and hurricanes, and the Integrated Multi-Satellite Retrievals for GPM product maps their intense rainfall rates over time to provide situational awareness for potential flood events. Following landfall, optical data collected by the Aqua, Terra, Landsat, or Suomi NPP satellites can map the extent and severity of flooding – and should clouds obscure the region, SAR data from ESA Sentinel satellites or NASA Airborne Science instruments can also be used to detect flooding. In addition to giving insights into how storms form and intensify, NASA satellites also supply key inputs to weather models to help generate life-saving forecasts.
Freight, smoke, and ozone impact the health of both Chicago residents and communities downwind. A NASA-led mission looks to help by mapping air pollutants at a neighborhood scale.
Credits: NASA/Kathleen Gaeta
It was a hazy August day on Chicago’s South Side, and Nedra Sims Fears was hosting a small gathering to talk about the air. Interstate-94, which bisects her Chatham neighborhood, hummed nearby.
“This was the summer I spent watching summer out my window,” Fears said.
That’s because asthma runs in her family, and smoke from wildfires in Canada had wafted into Chicago, making it difficult for her to breathe. Many of her neighbors don’t have air conditioning, which means they don’t have the luxury of shutting their windows against the tiny hazardous particles contained in the smoke.
Scott Collis of Argonne National Laboratory, left, and community leader Nedra Sims Fears work to advance urban resilience through science. They collaborated with NASA during the STAQS air quality mission in Chicago.
NASA/Kathleen Gaeta
The fine particles, called PM2.5, are more than 35 times smaller than a grain of sand and can infiltrate deep into lung tissue. They degrade air quality in Chicago neighborhoods that are already disproportionately exposed to fossil fuel emissions. These include South and West Side neighborhoods located near highways, warehouses, and intermodal facilities, where freight-loaded trains and trucks converge. Thousands of such facilities are spread throughout Illinois, and they are hot spots of diesel exhaust and nitrogen oxides.
“Walking down the road, you see truck after truck after truck going into these facilities,” said Fears, who leads the Greater Chatham Initiative to revitalize a host of South Side neighborhoods. “Those neighborhoods live with day-to-day air pollution. It doesn’t take Canada being on fire for them to suffer.”
This was the summer I spent watching summer out my window.
Nedra Sims Fears
Chicago community leader
The result is that residents of Chicago and communities downwind are breathing harmful air pollutants including PM2.5, fossil fuel emissions, and smog. These pollutants move throughout the atmosphere and change by the hour, periodically exceeding the levels considered safe by the U.S. Environmental Protection Agency.
A version of this story plays out in every city in America. In New York and Los Angeles, tailpipe emissions spew from congested streets. In Phoenix, record-breaking heat stokes ozone formation. In port cities like Baltimore and Houston, emissions from ships, as well as oil refineries and chemical plants, contribute to dirty air.
While air quality monitors are distributed throughout the country, they are sparse in some regions, which means they cannot tell every neighborhood’s story. A NASA mission aims to change that with new tools to monitor air pollutants from the streets to the stratosphere.
STAQing Up Observations
NASA and NOAA, among other agencies, worked together this summer through the STAQS and AEROMMA missions to calibrate and validate NASA’s new TEMPO satellite. The satellite and missions combined aim to not only better measure air quality, and the major pollutants that impact it, but also to improve air quality, from street to stratosphere. This effort was documented during the August 2023 campaign leg, which took place over the Chicago region. Credit: NASA/Kathleen Gaeta
Several thousand feet above the Fears’ home, one of the largest flying laboratories in the world circled the skies over Chicago.
The plane – NASA’s four-engine DC-8 jet – is a storied research craft. Over the past 25 years it has supported field campaigns across all seven continents. On this August 2023 day, it carried 40 researchers and a pack of scientific instruments investigating air pollution over the cities and pasturelands of the Midwest.
From his seat over the wing, Barry Lefer watched the city’s iconic skyline rise from Lake Michigan.
“Air pollution has dramatically improved across the U.S. in the past few decades due to environmental regulations, but some communities are still hot spots of poor air quality,” said Lefer, head of the Tropospheric Composition Program at NASA Headquarters in Washington.
The researchers onboard – from NASA, NOAA, and multiple universities – converged this summer on cities across North America. In coordinated research campaigns, they studied a range of air pollutants from industrial emissions to volatile chemical products used in cleaning agents and personal care items.
Crew member Matt Berry of NASA Armstrong smiles from the communications switchboard of NASA’s DC-8 airplane during a research flight over the Upper Midwest. Credit: NASA/Kathleen Gaeta
NASA’s part of the mission was called STAQS, short for Synergistic TEMPO Air Quality Science, and it focused on Chicago, New York City, Los Angeles, and Toronto. STAQS included two Gulfstream jets equipped with state-of-the-art sensors and ground crews deployed in mobile research trailers across the country.
At the heart of the mission were two overarching questions: How do air pollutants change and move through the atmosphere, and which communities are disproportionately exposed?
A Vivid New Picture
2023 was a noteworthy summer for another reason: More than 22,000 miles above Earth’s surface, a new NASA-funded instrument started scanning Earth. TEMPO, short for Tropospheric Emissions: Monitoring of Pollution, is the first space-based instrument designed to continuously measure daytime air quality over North America at the resolution of a few square miles. TEMPO launched in April, and NASA and the Smithsonian Astrophysical Observatory released its first data maps in August.
The Tropospheric Emissions: Monitoring of Pollution (TEMPO) instrument measures sunlight reflected and scattered off the Earth’s surface, clouds and the atmosphere. Gases in the atmosphere absorb the sunlight, and the resulting spectra are then used to determine the amounts of several gases in the Earth’s atmosphere, including nitrogen dioxide. Credit: NASA’s Scientific Visualization Studio/Kel Elkins
TEMPO plus field campaigns like STAQS are giving scientists a more vivid picture of the air pollutants that contribute to disease and premature deaths in the U.S. These include nitrogen oxides, a byproduct of fossil fuel combustion commonly emitted by tailpipes and smokestacks; aerosols such as dust and soot particles; volatile organic compounds; and heat-trapping greenhouse gases such as methane and water vapor. As that new data is gathered and analyzed, air pollution scientists will have details down to a level that matters to people on the street.
The data will be freely accessible, Lefer said, and particularly useful to researchers, state agencies, and local policymakers working to develop solutions. “The hope is that the detailed new data we’re collecting will help communities make their air safer to breathe,” Lefer said.
Ground-level ozone, a main ingredient in smog, is a particularly compelling target for Lefer and the STAQS team. While ozone high in the atmosphere protects Earth from dangerous solar radiation, ground-level ozone aggravates respiratory diseases. It often spikes after rush hour, as nitrogen oxides react with chemicals called volatile organic compounds and sunlight. Each year, ground-level ozone and PM2.5 particles lead to more than 100,000 premature deaths and billions of dollars in annual damages in the U.S, according to the National Weather Service.
In the Chicago area, Lake Michigan’s powerful influence on local weather and winds cause ozone plumes to “travel on air currents, causing pollution levels to exceed EPA standards in rural communities hundreds of miles away,” Lefer said.
Chemicals emitted from cars, trucks and factories react with sunlight and heat to form ozone, a key ingredient of smog. Plumes of ozone then get pushed by lake breezes into rural communities. Credit: NASA’s Goddard Space Flight Center/Conceptual Image Lab
Plume Over the Prairie
A short drive up Interstate-94 from Chicago, ozone was on the mind of Todd McKinney, who was scrambling in the dark. A raging Lake Michigan storm had knocked out power in his research trailer nestled in a Wisconsin prairie blooming with wildflowers just across the state line from Illinois. McKinney, a graduate student from the University of Alabama-Huntsville, was trying to get the lights back on before members of a Wisconsin environmental agency arrived for a tour.
For much of the summer, he has been living and working in the trailer, which is one part camper van, two parts high-tech laboratory. Its centerpiece is a custom-built lidar for measuring ozone in different layers of the lower atmosphere, also known as the troposphere. The mobile facility is part of NASA’s Tropospheric Ozone Lidar Network (TOLNet), a high-powered array of lasers used to identify and locate air pollutants.
Is the ozone that we’re seeing coming from an industrial source or the whole city? Is it caused by people idling in their cars at rush hour? We don’t know yet, but we’re working to track it back.
Todd McKinney
University of Alabama, Huntsville Graduate Student
The instruments were originally designed to be stationary. But McKinney said that the development of TEMPO was an inspiration for many researchers, who wanted to get out into the field and contribute real-time data to the summer’s air quality campaign. The trailer he’s working from has been in the making for 10 years – ever since the first announcement of TEMPO. Such ground-based measurements — which also include hourly drone flights and a continual stream of high-altitude weather balloons — help crosscheck the early data coming down from TEMPO in space.
Located downwind from Chicago, shoreline areas like Chiwaukee Prairie are occasionally dosed with ozone that has blown in from the city, he said. But the source is often difficult to pinpoint.
“Is the ozone that we’re seeing coming from an industrial source or the whole city?” he said. “Is it caused by people idling in their cars at rush hour? We don’t know yet, but we’re working to track it back.”
And tracking it back is the first step to developing a solution.
Empowering communities
Using advanced computer modeling to map air pollution hotspots across Chicago, a research team from Northwestern University found that neighborhoods alongside Lake Michigan experience more ground-level ozone pollution than the rest of the city. The researchers also found that neighborhoods located near highways like I-94 experience twice the concentration of nitrogen dioxide and dust than communities with the best air quality in the city.
The growth of online shopping and same-day delivery warehouses comes at a cost to air quality, with nearby homes taking on the burden of pollution. Credit: NASA’s Goddard Space Flight Center/Conceptual Image Lab
“Empowering communities with data is an environmental justice issue,” said Daniel Horton, assistant professor in the department of earth and planetary sciences at Northwestern, who leads this research. He hopes that NASA measurements will inform clean-air solutions, such as the electrification of heavy-duty trucks and buses, and more green space in urban neighborhoods.
Air pollution is not an intractable problem, emphasized Zac Adelman, whose regional consortium works with state agencies in the Upper Midwest to improve air quality. The solution lies in devoting resources where they’ll be most effective.
“The question is, what do we control?” said Adelman, executive director of the Lake Michigan Air Directors Consortium. “What are the sources that we need to be concerned about, and what’s actionable information that we can bring to the state regulators and to the federal government, too?”
Empowering communities with data is an environmental justice issue.
Daniel Horton
Northwestern University professor and researcher
“The STAQS campaign and associated monitoring activities that are growing up around it are giving us an opportunity to try to answer those questions,” he added. “That’s a pretty empowering concept, right?”
Sacred Space Requires Clean Air
Back in her living room, Nedra Fears and atmospheric scientist Scott Collis of Argonne National Laboratory discussed how more trees, open spaces, and green rooftops might improve air quality in hard-hit neighborhoods. It’s part of a project they’re collaborating on called CROCUS, short for Community Research on Climate and Urban Science.
Combining scientific research and community guidance, the CROCUS team studies climate challenges in urban Chicago. Community input is critical, Collis said, to identify questions and topics – from localized flooding to heat waves – and ensure that research results directly benefit local residents. The team contributed to the summer’s air quality campaign using a network of sensors deployed throughout the region. CROCUS is funded by the Department of Energy.
Air quality is a complicated issue, but for Fears, the goal is simple. She wants to go on morning walks with her husband. She wants her neighbors’ concerns to be heard. Mostly, she wants to breathe clean air in her own living room, not shut the windows against the pollution she can often feel at the back of her throat.
“You don’t want that pollution in your house,” she said. “Your house is your sacred space where you can be joyful and well.”
Story by Sally Younger. Video and stills by Kathleen Gaeta.
