Archivo del Autor: admin

This US-Indian Satellite Will Monitor Earth’s Changing Frozen Regions

por | |
Deja un comentario

This US-Indian Satellite Will Monitor Earth’s Changing Frozen Regions

Satellite imagery shows a portion of East Antarctica on Jan. 9, 2022, before icebergs calved off the Glenzer and Conger glaciers. NISAR will observe nearly all of the planet’s land and ice surfaces twice every 12 days, monitoring Earth’s frozen regions, known as the cryosphere.
Satellite imagery shows a portion of East Antarctica on Jan. 9, 2022, before icebergs calved off the Glenzer and Conger glaciers. NISAR will observe nearly all of the planet’s land and ice surfaces twice every 12 days, monitoring Earth’s frozen regions, known as the cryosphere.
USGS

Much of the Glenzer and Conger glaciers had collapsed by March 23, 2022, spawning numerous icebergs, as shown in this satellite image. NISAR will document such changes around the globe, and its geographic coverage of Antarctica will be the most extensive for a radar satellite mission to date.
Much of the Glenzer and Conger glaciers had collapsed by March 23, 2022, spawning numerous icebergs, as shown in this satellite image. NISAR will document such changes around the globe, and its geographic coverage of Antarctica will be the most extensive for a radar satellite mission to date.
USGS


NISAR will study changes to ice sheets, glaciers, and sea ice in fine detail, as climate change warms the air and ocean.

NISAR, the soon-to-launch radar satellite from NASA and the Indian Space Research Organisation (ISRO), will measure some key Earth vital signs, from the health of wetlands to ground deformation by volcanoes to the dynamics of land and sea ice.

This last capability will help researchers decipher how small-scale processes can cause monumental changes in the ice sheets covering Antarctica and Greenland, as well as on mountain glaciers and sea ice around the world.

Short for NASA-ISRO Synthetic Aperture Radar, NISAR will provide the most comprehensive picture to date of motion and deformation of frozen surfaces in Earth’s ice- and snow-covered environments, collectively known as the cryosphere.

“Our planet has the thermostat set on high, and Earth’s ice is responding by speeding up its motion and melting faster,” said Alex Gardner, a glaciologist at NASA’s Jet Propulsion Laboratory in Southern California. “We need to better understand the processes at play, and NISAR will provide measurements to do that.”

NASA and the Indian Space Research Organisation have teamed up to create NISAR, a new satellite mission that will track the changing Earth in fine detail. Learn how NISAR will use radar to deepen our understanding of deforestation, shrinking glaciers, natural hazards, and other global vital signs. Credit: NASA/JPL-Caltech

Set to be launched in 2024 by ISRO from southern India, NISAR will observe nearly all the planet’s land and ice surfaces twice every 12 days. The satellite’s unique insights into Earth’s cryosphere will come from the combined use of two radars: an L-band system with a 10-inch (25-centimeter) wavelength and an S-band system with a 4-inch (10-centimeter) wavelength.

L-band can see through snow, helping scientists better track the motion of ice underneath, while S-band is more sensitive to snow moisture, which indicates melting. Both signals penetrate clouds and darkness, enabling observations during monthslong polar winter nights.

‘Time-Lapse Movie’ of Ice Sheets

NISAR’s orientation in orbit will enable it to collect data from Antarctica’s far interior, close to the South Pole – unlike other large imaging radar satellites, which have more extensively covered the Arctic.

Antarctica’s ice sheets hold the planet’s largest reservoir of frozen fresh water, and the rate at which it may lose ice represents the greatest uncertainty in sea level rise projections. NISAR’s increased coverage will be crucial for studying the motion of ice flowing down from central Antarctica’s high elevations toward the sea.

The measurements will also enable scientists to closely study what happens where ice and ocean meet. For example, when parts of an ice sheet sit on ground that is below sea level, saltwater can seep under the ice and increase melting and instability. Both Antarctica and Greenland also have ice shelves – masses of ice that extend from land and float on the ocean – that are thinning and crumbling as icebergs break off. Ice shelves help keep glacial ice on the land from slipping into the ocean. If they are diminished, glaciers can flow and calve faster.

Pictured in this artist’s concept, NISAR will use two radar systems to monitor change in nearly all of Earth’s land and ice surfaces. The satellite marks the first time the U.S. and Indian space agencies have cooperated on hardware development for an Earth-observing mission.
NASA/JPL-Caltech

Ice losses on both Antarctica and Greenland have accelerated since the 1990s, and there’s uncertainty about how quickly each will continue to recede. NISAR will improve our horizontal and vertical views of these changes.

“NISAR will give us a consistent time-lapse movie of that motion, so we can understand how and why it’s changing and better predict how it will change into the future,” said Ian Joughin, a glaciologist at the University of Washington in Seattle and the NISAR cryosphere lead.

Mountain Glaciers, Water Supply, and Flooding

The satellite will also track changes in Earth’s mountain glaciers. Their melting has contributed about a third of the sea level rise seen since the 1960s, and climate-driven changes to freezing and thawing patterns can affect the water supplies of downstream populations.

In the Himalayas, NISAR’s all-weather capability will help researchers monitor how much water is stored in glacial lakes, which is essential to assessing the risk of catastrophic floods.

“The beauty and the difficulty of the Himalayas are the clouds,” said Sushil Kumar Singh, a glaciologist at the ISRO Space Applications Centre in Ahmedabad, India. “With NISAR we will be able to get a more continuous and complete data set that would not be possible with instruments that use visible light.”

Sea Ice Dynamics Near Both Poles

NISAR will also capture the movement and extent of sea ice in both hemispheres. Sea ice insulates the ocean from the air, reducing evaporation and heat loss to the atmosphere. It also reflects sunlight, keeping the planet cool through the albedo effect.

Arctic sea ice has been diminishing for decades as rising water and air temperatures have increased melting. With more of its surface exposed to sunlight, the Arctic Ocean gains and holds more heat in summer and takes longer to cool. This means less ice formation in winter and faster melting the next summer, said Ben Holt, a JPL sea-ice scientist.

With greater coverage of the Southern Ocean than any radar mission to date, NISAR will open new insights around Antarctica, where sea ice had mostly been more stable until the past few years. It reached a record low in 2023.

More About the Mission

NISAR is an equal collaboration between NASA and ISRO and marks the first time the two agencies have cooperated on hardware development for an Earth-observing mission. NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech in Pasadena, California, leads the U.S. component of the project and is providing the mission’s L-band SAR. NASA is also providing the radar reflector antenna, the deployable boom, a high-rate communication subsystem for science data, GPS receivers, a solid-state recorder, and payload data subsystem. U R Rao Satellite Centre (URSC) in Bengaluru, which leads the ISRO component of the mission, is providing the spacecraft bus, the launch vehicle, and associated launch services and satellite mission operations. ISRO’s Space Applications Centre in Ahmedabad is providing the S-band SAR electronics.

To learn more about NISAR, visit:

https://nisar.jpl.nasa.gov/


See NISAR in 3D with NASA’s Eyes on Earth


How NISAR will monitor change in forest and wetland ecosystems


NISAR put to the test in preparation for launch

News Media Contacts

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

2024-001

Powered by WPeMatico

Get The Details…
Naomi Hartono

NASA’s Webb Discovers Dusty ‘Cat’s Tail’ in Beta Pictoris System

por | |
Deja un comentario

NASA’s Webb Discovers Dusty ‘Cat’s Tail’ in Beta Pictoris System

6 Min Read

NASA’s Webb Discovers Dusty ‘Cat’s Tail’ in Beta Pictoris System

Star system Beta Pictoris. A thin, elongated horizontal orange line appears at the center of the frame, extending almost to the edges. This is a debris disk seen edge-on. A thin blue-green disk is inclined about five degrees counterclockwise relative to the orange main disk. Cloudy, translucent gray material is most prominent near the orange main debris disk. Some of the gray material forms a curved feature in the upper right, resembling a cat’s tail. The central star, represented as a small white star icon, is blocked by an instrument known as a coronagraph, which forms a large black circle at center and two small disks pointing to the upper left and lower right. The background of space is black.

This image from Webb’s MIRI (Mid-Infrared Instrument) shows the star system Beta Pictoris.

Credits:
NASA, ESA, CSA, STScI, C. Stark and K. Lawson (NASA GSFC), J. Kammerer (ESO), and M. Perrin (STScI).

Beta Pictoris, a young planetary system located just 63 light-years away, continues to intrigue scientists even after decades of in-depth study. It possesses the first dust disk imaged around another star — a disk of debris produced by collisions between asteroids, comets, and planetesimals. Observations from NASA’s Hubble Space Telescope revealed a second debris disk in this system, inclined with respect to the outer disk, which was seen first. Now, a team of astronomers using NASA’s James Webb Space Telescope to image the Beta Pictoris system (Beta Pic) has discovered a new, previously unseen structure.

The team, led by Isabel Rebollido of the Astrobiology Center in Spain, used Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to investigate the composition of Beta Pic’s previously detected main and secondary debris disks. The results exceeded their expectations, revealing a sharply inclined branch of dust, shaped like a cat’s tail, that extends from the southwest portion of the secondary debris disk.

Image: Star System Beta Pictoris

Star system Beta Pictoris. A thin, elongated horizontal orange line appears at the center of the frame, extending almost to the edges. This is a debris disk seen edge-on. A thin blue-green disk is inclined about five degrees counterclockwise relative to the orange main disk. Cloudy, translucent gray material is most prominent near the orange main debris disk. Some of the gray material forms a curved feature in the upper right, resembling a cat’s tail. The central star, represented as a small white star icon, is blocked by an instrument known as a coronagraph, which forms a large black circle at center and two small disks pointing to the upper left and lower right. The background of space is black.
This image from Webb’s MIRI (Mid-Infrared Instrument) shows the star system Beta Pictoris. An edge-on disk of dusty debris generated by collisions between planetesimals (orange) dominates the view. A hotter, secondary disk (cyan) is inclined by about 5 degrees relative to the primary disk. The curved feature at upper right, which the science team nicknamed the “cat’s tail,” has never been seen before. A coronagraph (black circle and two small disks) has been used to block the light of the central star, whose location is marked with a white star shape. In this image light at 15.5 microns is colored cyan and 23 microns is orange (filters F1550C and F2300C, respectively).
NASA, ESA, CSA, STScI, C. Stark and K. Lawson (NASA GSFC), J. Kammerer (ESO), and M. Perrin (STScI).

“Beta Pictoris is the debris disk that has it all: It has a really bright, close star that we can study very well, and a complex cirumstellar environment with a multi-component disk, exocomets, and two imaged exoplanets,” said Rebollido, lead author of the study. “While there have been previous observations from the ground in this wavelength range, they did not have the sensitivity and the spatial resolution that we now have with Webb, so they didn’t detect this feature.”

A Star’s Portrait Improved with Webb

Even with Webb or JWST, peering at Beta Pic in the right wavelength range — in this case, the mid-infrared — was crucial to detect the cat’s tail, as it only appeared in the MIRI data. Webb’s mid-infrared data also revealed differences in temperature between Beta Pic’s two disks, which likely is due to differences in composition.

“We didn’t expect Webb to reveal that there are two different types of material around Beta Pic, but MIRI clearly showed us that the material of the secondary disk and cat’s tail is hotter than the main disk,” said Christopher Stark, a co-author of the study at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The dust that forms that disk and tail must be very dark, so we don’t easily see it at visible wavelengths — but in the mid-infrared, it’s glowing.”

To explain the hotter temperature, the team deduced that the dust may be highly porous “organic refractory material,” similar to the matter found on the surfaces of comets and asteroids in our solar system. For example, a preliminary analysis of material sampled from asteroid Bennu by NASA’s OSIRIS-REx mission found it to be very dark and carbon-rich, much like what MIRI detected at Beta Pic.

Image: Annotated Image

Star system Beta Pictoris with labels and graphic overlays. A thin, elongated horizontal orange line appears at the center of the frame, extending almost to the edges. This is a debris disk seen edge-on. A white line traces over the orange debris disk and is labeled “main disk plane.” A thin blue-green disk is inclined about five degrees counterclockwise relative to the orange main disk and is highlighted by a blue-green line labeled “extended secondary disk.” Cloudy, translucent gray material is most prominent near the orange main debris disk. Some of the gray material forms a curved feature in the upper right and is marked with a yellow line labeled “cat’s tail.” The central star, represented as a small white star icon, is blocked by an instrument known as a coronagraph, which forms a large black circle at center and two small disks pointing to the upper left and lower right. The background of space is black. In the lower right corner is a white bar labeled “100 A U.”
This image from Webb’s MIRI (Mid-Infrared Instrument) shows the star system Beta Pictoris. An edge-on disk of dusty debris generated by collisions between planetesimals (orange) dominates the view and is labeled “main disk plane.” While a secondary disk (cyan), inclined 5 degrees relative to the main disk, was already known, Webb showed its true extent at lower left. Webb also detected a never-before-seen feature labeled the cat’s tail. A coronagraph (black circle and two small disks) has been used to block the light of the central star. A scale bar shows that the disks of Beta Pic extend for hundreds of astronomical units (AU), where one AU is the average Earth-Sun distance. (In our solar system, Neptune orbits 30 AU from the sun.) In this image light at 15.5 microns is colored cyan and 23 microns is orange (filters F1550C and F2300C, respectively).
NASA, ESA, CSA, STScI, C. Stark and K. Lawson (NASA GSFC), J. Kammerer (ESO), and M. Perrin (STScI).

The Tail’s Puzzling Beginning Warrants Future Research

However, a major lingering question remains: What could explain the shape of the cat’s tail, a uniquely curved feature unlike what is seen in disks around other stars?

Rebollido and the team modeled various scenarios in an attempt to emulate the cat’s tail and unravel its origins. Though further research and testing is required, the team presents a strong hypothesis that the cat’s tail is the result of a dust production event that occurred a mere one hundred years ago.

“Something happens — like a collision — and a lot of dust is produced,” shared Marshall Perrin, a co-author of the study at the Space Telescope Science Institute in Baltimore, Maryland. “At first, the dust goes in the same orbital direction as its source, but then it also starts to spread out. The light from the star pushes the smallest, fluffiest dust particles away from the star faster, while the bigger grains do not move as much, creating a long tendril of dust.”

“The cat’s tail feature is highly unusual, and reproducing the curvature with a dynamical model was difficult,” explained Stark. “Our model requires dust that can be pushed out of the system extremely rapidly, which again suggests it’s made of organic refractory material.”

Animation: Cat’s Tail Creation

This is an animation portraying the creation of the cat’s tail, as hypothesized by a team of astronomers. The cat’s tail may be the result of a dust production event — like a collision — that occurred a mere one hundred years ago. This tendril of dust, which is seen in the southwest portion of Beta Pic’s secondary debris disk, is estimated to span 10 billion miles.
Credit: NASA, ESA, CSA, STScI, R. Crawford (STScI), C. Stark (NASA-GSFC), M. Perrin (STScI), and I. Rebollido (Astrobiology Center).

The team’s preferred model explains the sharp angle of the tail away from the disk as a simple optical illusion. Our perspective combined with the curved shape of the tail creates the observed angle of the tail, while in fact, the arc of material is only departing from the disk at a five-degree incline. Taking into consideration the tail’s brightness, the team estimates the amount of dust within the cat’s tail to be equivalent to a large main belt asteroid spread out across 10 billion miles.

A recent dust production event within Beta Pic’s debris disks could also explain a newly-seen asymmetric extension of the inclined inner disk, as shown in the MIRI data and seen only on the side opposite of the tail. Recent collisional dust production could also account for a feature previously spotted by the Atacama Large Millimeter/submillimeter Array in 2014: a clump of carbon monoxide (CO) located near the cat’s tail. Since the star’s radiation should break down CO within roughly one hundred years, this still-present concentration of gas could be lingering evidence of the same event.

“Our research suggests that Beta Pic may be even more active and chaotic than we had previously thought,” said Stark. “JWST continues to surprise us, even when looking at the most well-studied objects. We have a completely new window into these planetary systems.”

These results were presented in a press conference at the 243rd meeting of the American Astronomical Society in New Orleans, Louisiana.

The observations were taken as part of Guaranteed Time Observation program 1411.

The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency

Downloads

Download full resolution images for this article from the Space Telescope Science Institute.

Right click the images in this article to open a larger version in a new tab/window.

Media Contacts

Laura Betz – laura.e.betz@nasa.gov, Rob Gutro– rob.gutro@nasa.gov
NASA’s  Goddard Space Flight Center, , Greenbelt, Md.

Abigail Major amajor@stsci.edu, Christine Pulliam – cpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.

Related Information

About protoplanetary disks

LIfe and Death of a Planetary System

More Webb News – https://science.nasa.gov/mission/webb/latestnews/

More Webb Images – https://science.nasa.gov/mission/webb/multimedia/images/

Webb Mission Page – https://science.nasa.gov/mission/webb/

Related For Kids

How did our Solar System Form?

What is the Webb Telescope?

SpacePlace for Kids

En Español

Ciencia de la NASA

NASA en español 

Space Place para niños

Keep Exploring

Related Topics

James Webb Space Telescope

Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…


Stars

Overview Stars are giant balls of hot gas – mostly hydrogen, with some helium and small amounts of other elements.…


Planets

Our solar system has eight planets, and five dwarf planets – all located in an outer spiral arm of the…


Our Solar System

Overview Our planetary system is located in an outer spiral arm of the Milky Way galaxy. We call it the…

Share

Details

Last Updated

Jan 10, 2024

Related Terms

Powered by WPeMatico

Get The Details…
Steve Sabia

Discovery Alert: Earth-sized Planet Has a ‘Lava Hemisphere’

por | |
Deja un comentario

Discovery Alert: Earth-sized Planet Has a ‘Lava Hemisphere’

4 min read

Discovery Alert: Earth-sized Planet Has a ‘Lava Hemisphere’

An artist's concept illustration shows a planet large in the frame and back-lit by a nearby bright yellow star. Another planet in the system can be seen as a black dot crossing the face of the star against the background of space.
Like Kepler-10 b, illustrated above, the exoplanet HD 63433 d is a small, rocky planet in a tight orbit of its star. HD 63433 d is the smallest confirmed exoplanet younger than 500 million years old. It’s also the closest discovered Earth-sized planet this young, at about 400 million years old.
NASA/Ames/JPL-Caltech/T. Pyle

The discovery: In a system with two known planets, astronomers spotted something new: a small object transiting across the Sun-sized star. This turned out to be another planet: extra hot and Earth-sized.

Key Facts: The newly-spotted planet, called HD 63433 d, is tidally locked, meaning there is a dayside which always faces its star and a side that is constantly in darkness. This exoplanet, or planet outside of our solar system, orbits around the star HD 63433 (TOI 1726) in the HD 63433 planetary system. This scorching world is the smallest confirmed exoplanet younger than 500 million years old. It’s also the closest discovered Earth-sized planet this young, at about 400 million years old.


The Planet That Shouldn’t Be There


15 Years of Exoplanet Images

Details: A team of astronomers analyzed this system using data from NASA’s TESS (Transiting Exoplanet Survey Satellite), which spots “transits,” or instances where planets cross in front of their star as they orbit, blocking a tiny piece of the starlight. Two planets had already been previously discovered in this planetary system, so to see what else might be lurking in the star’s orbit, the team took the data and removed the signals of the

two known planets. This allowed them to see an additional signal – a small transit that would reappear every 4.2 days. Upon further investigation, they were able to validate that this was actually a third, smaller planet.

The tidally locked planet is very close to Earth size (it is approximately 1.1 times the diameter of our own planet) and it’s orbiting a star that’s similar to the size of our Sun (the star is about 0.91 the size and 0.99 the mass of the Sun).

The star in this system is a G-type star, the same type as our Sun. But HD 63433 d orbits much closer to its star than we do, with a minuscule 4.2 day long “year” and extremely high temperatures on its dayside. 

Fun Facts: While this newly found planet and its star are just about the size of our own planet and Sun, HD 63433 d is quite different from our home world.

Firstly, it is a very young planet in a very young system. The planetary system itself is about 10 times younger than ours and this 400-million-year-old planet is in its infancy compared to our 4.5-billion-year-old world.

It is also much closer to its star than we are to ours. This planet is 8 times closer to its star than Mercury is to the Sun. Being so close to its star, this dayside of this tidally-locked planet can reach temperatures of about 2,294 Fahrenheit (1,257 Celsius). Being so hot, so close to its star, and so small, this planet likely lacks a substantial atmosphere.

These scorching temperatures are comparable to lava worlds like CoRoT-7 b and Kepler-10 b, and the team behind this discovery thinks that the planet’s dayside could be a “lava hemisphere.”

The planet’s small size, young age, and closeness to its star make it an interesting candidate for further exploration. Follow-up study could confirm the results of this study and potentially reveal more information about the planet’s “dark side,” and the status of its (possible) atmosphere. As this study states, “Young terrestrial worlds are critical test beds to constrain prevailing theories of planetary formation and evolution.”

The Discoverers: This discovery was described in a new study, accepted for publication in the Astronomical Journal, titled “TESS Hunt for Young and Maturing Exoplanets (THYME) XI: An Earth-sized Planet Orbiting a Nearby, Solar-like Host in the 400 Myr Ursa Major Moving Group.” The study, led by co-authors Benjamin Capistrant and Melinda Soares-Furtado, will be discussed in a Jan. 10 presentation at the 2024 American Astronomical Society Meeting.

This study was conducted as part of the TESS Hunt for Young and Maturing Exoplanets, which is a project focused on searching for young exoplanets that are in moving groups, stellar associations, or open clusters.

Read the paper.

Explore More

5 min read

NASA Features New Discoveries at American Astronomical Society Meeting



Article


5 days ago

4 min read

NASA’s Hubble Observes Exoplanet Atmosphere Changing Over 3 Years



Article


6 days ago

5 min read

Seeing and Believing: 15 Years of Exoplanet Images

Fifteen years ago, astronomers delivered what is now an iconic direct image of an exoplanet,…



Article


4 weeks ago

Powered by WPeMatico

Get The Details…

Artemis Media Resources

por | |
Deja un comentario

Artemis Media Resources

​Media Contacts

NASA Headquarters: Kathryn Hambleton, Rachel Kraft, Vanessa Lloyd, 202-358-1100

Latest Updates: Artemis blog

Briefings

Artemis Update (Jan 9, 2024)

Related Resources

Artemis WHAT/WHY/HOW
Artemis Accords

Program and Project Resources
Education and STEM Engagement

Broadcast and Historical Resources

Artemis B-roll

Artemis Imagery
Q&A with NASA Administrator Bill Nelson
Q&A with Deputy Administrator Pam Melroy
Q&A with Associate Administrator Bob Cabana

Keep Exploring

Discover More Artemis

Artemis


Artemis News and Articles


Artemis II News and Updates


Artemis III News and Updates

Powered by WPeMatico

Get The Details…
Kathryn Hambleton

Orbital-1 Launch’s 10th Anniversary

por | |
Deja un comentario

Orbital-1 Launch’s 10th Anniversary

A white rocket launches upward, leaving a short trail of vapor behind it. The flame at the bottom of the rocket is a bright spot near the center of the photo. To the left of the rocket is a white tower and other structures. Thick plumes of white smoke frame the field in the foreground.
NASA/Bill Ingalls

An Orbital Sciences Corporation (now Northrop Grumman) Antares rocket carrying the Cygnus spacecraft launches from NASA’s Wallops Flight Facility in Virginia on Thursday, January 9, 2014. The Orbital-1 mission was Orbital Sciences’ first contracted cargo delivery flight to the space station for NASA. Cygnus brought science experiments, crew provisions, spare parts and other hardware to the space station. One NASA experiment studied the decreased effectiveness of antibiotics during spaceflight, while another examined how different fuel samples burned in microgravity.

Learn more about the first operational Cygnus cargo mission.

Image Credit: NASA/Bill Ingalls

Powered by WPeMatico

Get The Details…
Monika Luabeya