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Earth orbit, Moon, Mars: ESA’s ambitious roadmap
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By NASA
5 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
Typically, asteroids — like the one depicted in this artist’s concept — originate from the main asteroid belt between the orbits of Mars and Jupiter, but a small population of near-Earth objects may also come from the Moon’s surface after being ejected into space by an impact.NASA/JPL-Caltech The near-Earth object was likely ejected into space after an impact thousands of years ago. Now it could contribute new insights to asteroid and lunar science.
The small near-Earth object 2024 PT5 captured the world’s attention last year after a NASA-funded telescope discovered it lingering close to, but never orbiting, our planet for several months. The asteroid, which is about 33 feet (10 meters) wide, does not pose a hazard to Earth, but its orbit around the Sun closely matches that of our planet, hinting that it may have originated nearby.
As described in a study published Jan. 14 in the Astrophysical Journal Letters, researchers have collected further evidence of 2024 PT5 being of local origin: It appears to be composed of rock broken off from the Moon’s surface and ejected into space after a large impact.
“We had a general idea that this asteroid may have come from the Moon, but the smoking gun was when we found out that it was rich in silicate minerals — not the kind that are seen on asteroids but those that have been found in lunar rock samples,” said Teddy Kareta, an astronomer at Lowell Observatory in Arizona, who led the research. “It looks like it hasn’t been in space for very long, maybe just a few thousand years or so, as there’s a lack of space weathering that would have caused its spectrum to redden.”
The asteroid was first detected on Aug. 7, 2024, by the NASA-funded Sutherland, South Africa, telescope of the University of Hawai’i’s Asteroid Terrestrial-impact Last Alert System (ATLAS). Kareta’s team then used observations from the Lowell Discovery Telescope and the NASA Infrared Telescope Facility (IRTF) at the Mauna Kea Observatory in Hawai’i to show that the spectrum of reflected sunlight from the small object’s surface didn’t match that of any known asteroid type; instead, the reflected light more closely matched rock from the Moon.
Not (Old) Rocket Science
A second clue came from observing how the object moves. Along with asteroids, Space Age debris, such as old rockets from historic launches, can also be found in Earth-like orbits.
The difference in their orbits has to do with how each type responds to solar radiation pressure, which comes from the momentum of photons — quantum particles of light from the Sun — exerting a tiny force when they hit a solid object in space. This momentum exchange from many photons over time can push an object around ever so slightly, speeding it up or slowing it down. While a human-made object, like a hollow rocket booster, will move like an empty tin can in the wind, a natural object, such as an asteroid, will be much less affected.
Researchers studying asteroid 2024 PT5 have plotted its looping motion on two graphs. To a trained eye, they show that the object never gets captured by Earth’s gravity but, instead, lingers nearby before continuing its orbit around the Sun. NASA/JPL-Caltech To rule out 2024 PT5 being space junk, scientists at NASA’s Center for Near Earth Object Studies (CNEOS), which is managed by the agency’s Jet Propulsion Laboratory in Southern California, analyzed its motion. Their precise calculations of the object’s motion under the force of gravity ultimately enabled them to search for additional motion caused by solar radiation pressure. In this case, the effects were found to be too small for the object to be artificial, proving 2024 PT5 is most likely of natural origin.
“Space debris and space rocks move slightly differently in space,” said Oscar Fuentes-Muñoz, a study coauthor and NASA postdoctoral fellow at JPL working with the CNEOS team. “Human-made debris is usually relatively light and gets pushed around by the pressure of sunlight. That 2024 PT5 doesn’t move this way indicates it is much denser than space debris.”
Asteroid Lunar Studies
The discovery of 2024 PT5 doubles the number of known asteroids thought to originate from the Moon. Asteroid 469219 Kamo’oalewa was found in 2016 with an Earth-like orbit around the Sun, indicating that it may also have been ejected from the lunar surface after a large impact. As telescopes become more sensitive to smaller asteroids, more potential Moon boulders will be discovered, creating an exciting opportunity not only for scientists studying a rare population of asteroids, but also for scientists studying the Moon.
If a lunar asteroid can be directly linked to a specific impact crater on the Moon, studying it could lend insights into cratering processes on the pockmarked lunar surface. Also, material from deep below the lunar surface — in the form of asteroids passing close to Earth — may be accessible to future scientists to study.
“This is a story about the Moon as told by asteroid scientists,” said Kareta. “It’s a rare situation where we’ve gone out to study an asteroid but then strayed into new territory in terms of the questions we can ask of 2024 PT5.”
The ATLAS, IRTF, and CNEOS projects are funded by NASA’s planetary defense program, which is managed by the Planetary Defense Coordination Office at NASA Headquarters in Washington.
For more information about asteroids and comets, visit:
https://www.jpl.nasa.gov/topics/asteroids/
NASA Asteroid Experts Create Hypothetical Impact Scenario for Exercise NASA Researchers Discover More Dark Comets Lesson Plan: How to Explore an Asteroid News Media Contacts
Ian J. O’Neill
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-2649
ian.j.oneill@jpl.nasa.gov
Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
Kevin Schindler
Lowell Observatory Public Information Officer
928-607-1387
kevin@lowell.edu
2025-007
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Last Updated Jan 22, 2025 Related Terms
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By NASA
NASA’s Jet Propulsion Laboratory used radar data taken by ESA’s Sentinel-1A satellite before and after the 2015 eruption of the Calbuco volcano in Chile to create this inter-ferogram showing land deformation. The color bands west of the volcano indicate land sinking. NISAR will produce similar images.ESA/NASA/JPL-Caltech A SAR image — like ones NISAR will produce — shows land cover on Mount Okmok on Alaska’s Umnak Island . Created with data taken in August 2011 by NASA’s UAVSAR instrument, it is an example of polarimetry, which measures return waves’ orientation relative to that of transmitted signals.NASA/JPL-Caltech Data from NASA’s Magellan spacecraft, which launched in 1989, was used to create this image of Crater Isabella, a 108-mile-wide (175-kilometer-wide) impact crater on Venus’ surface. NISAR will use the same basic SAR principles to measure properties and characteristics of Earth’s solid surfaces.NASA/JPL-Caltech Set to launch within a few months, NISAR will use a technique called synthetic aperture radar to produce incredibly detailed maps of surface change on our planet.
When NASA and the Indian Space Research Organization’s (ISRO) new Earth satellite NISAR (NASA-ISRO Synthetic Aperture Radar) launches in coming months, it will capture images of Earth’s surface so detailed they will show how much small plots of land and ice are moving, down to fractions of an inch. Imaging nearly all of Earth’s solid surfaces twice every 12 days, it will see the flex of Earth’s crust before and after natural disasters such as earthquakes; it will monitor the motion of glaciers and ice sheets; and it will track ecosystem changes, including forest growth and deforestation.
The mission’s extraordinary capabilities come from the technique noted in its name: synthetic aperture radar, or SAR. Pioneered by NASA for use in space, SAR combines multiple measurements, taken as a radar flies overhead, to sharpen the scene below. It works like conventional radar, which uses microwaves to detect distant surfaces and objects, but steps up the data processing to reveal properties and characteristics at high resolution.
To get such detail without SAR, radar satellites would need antennas too enormous to launch, much less operate. At 39 feet (12 meters) wide when deployed, NISAR’s radar antenna reflector is as wide as a city bus is long. Yet it would have to be 12 miles (19 kilometers) in diameter for the mission’s L-band instrument, using traditional radar techniques, to image pixels of Earth down to 30 feet (10 meters) across.
Synthetic aperture radar “allows us to refine things very accurately,” said Charles Elachi, who led NASA spaceborne SAR missions before serving as director of NASA’s Jet Propulsion Laboratory in Southern California from 2001 to 2016. “The NISAR mission will open a whole new realm to learn about our planet as a dynamic system.”
Data from NASA’s Magellan spacecraft, which launched in 1989, was used to create this image of Crater Isabella, a 108-mile-wide (175-kilometer-wide) impact crater on Venus’ surface. NISAR will use the same basic SAR principles to measure properties and characteristics of Earth’s solid surfaces.NASA/JPL-Caltech How SAR Works
Elachi arrived at JPL in 1971 after graduating from Caltech, joining a group of engineers developing a radar to study Venus’ surface. Then, as now, radar’s allure was simple: It could collect measurements day and night and see through clouds. The team’s work led to the Magellan mission to Venus in 1989 and several NASA space shuttle radar missions.
An orbiting radar operates on the same principles as one tracking planes at an airport. The spaceborne antenna emits microwave pulses toward Earth. When the pulses hit something — a volcanic cone, for example — they scatter. The antenna receives those signals that echo back to the instrument, which measures their strength, change in frequency, how long they took to return, and if they bounced off of multiple surfaces, such as buildings.
This information can help detect the presence of an object or surface, its distance away, and its speed, but the resolution is too low to generate a clear picture. First conceived at Goodyear Aircraft Corp. in 1952, SAR addresses that issue.
“It’s a technique to create high-resolution images from a low-resolution system,” said Paul Rosen, NISAR’s project scientist at JPL.
As the radar travels, its antenna continuously transmits microwaves and receives echoes from the surface. Because the instrument is moving relative to Earth, there are slight changes in frequency in the return signals. Called the Doppler shift, it’s the same effect that causes a siren’s pitch to rise as a fire engine approaches then fall as it departs.
Computer processing of those signals is like a camera lens redirecting and focusing light to produce a sharp photograph. With SAR, the spacecraft’s path forms the “lens,” and the processing adjusts for the Doppler shifts, allowing the echoes to be aggregated into a single, focused image.
Using SAR
One type of SAR-based visualization is an interferogram, a composite of two images taken at separate times that reveals the differences by measuring the change in the delay of echoes. Though they may look like modern art to the untrained eye, the multicolor concentric bands of interferograms show how far land surfaces have moved: The closer the bands, the greater the motion. Seismologists use these visualizations to measure land deformation from earthquakes.
Another type of SAR analysis, called polarimetry, measures the vertical or horizontal orientation of return waves relative to that of transmitted signals. Waves bouncing off linear structures like buildings tend to return in the same orientation, while those bouncing off irregular features, like tree canopies, return in another orientation. By mapping the differences and the strength of the return signals, researchers can identify an area’s land cover, which is useful for studying deforestation and flooding.
Such analyses are examples of ways NISAR will help researchers better understand processes that affect billions of lives.
“This mission packs in a wide range of science toward a common goal of studying our changing planet and the impacts of natural hazards,” said Deepak Putrevu, co-lead of the ISRO science team at the Space Applications Centre in Ahmedabad, India.
Learn more about NISAR at:
https://nisar.jpl.nasa.gov
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
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Last Updated Jan 21, 2025 Related Terms
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By NASA
4 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
A test rover with shape memory alloy spring tires traverses rocky, Martian-simulated terrain.Credit: NASA The mystique of Mars has been studied for centuries. The fourth planet from the Sun is reminiscent of a rich, red desert and features a rugged surface challenging to traverse. While several robotic missions have landed on Mars, NASA has only explored 1% of its surface. Ahead of future human and robotic missions to the Red Planet, NASA recently completed rigorous rover testing on Martian-simulated terrain, featuring revolutionary shape memory alloy spring tire technology developed at the agency’s Glenn Research Center in Cleveland in partnership with Goodyear Tire & Rubber.
Rovers — mobile robots that explore lunar or planetary surfaces — must be equipped with adequate tires for the environments they’re exploring. As Mars has an uneven, rocky surface, durable tires are essential for mobility. Shape memory alloy (SMA) spring tires help make that possible.
Shape memory alloys are metals that can return to their original shape after being bent, stretched, heated, and cooled. NASA has used them for decades, but applying this technology to tires is a fairly new concept.
“We at Glenn are one of the world leaders in bringing the science and understanding of how you change the alloy compositions, how you change the processing of the material, and how you model these systems in a way that we can control and stabilize the behaviors so that they can actually be utilized in real applications,” said Dr. Santo Padula II, materials research engineer at NASA Glenn.
Researchers from NASA’s Glenn Research Center and Airbus Defence & Space pose with a test rover on Martian-simulated terrain.Credit: NASA Padula and his team have tested several applications for SMAs, but his epiphany of the possibilities for tires came about because of a chance encounter.
While leaving a meeting, Padula encountered Colin Creager, a mechanical engineer at NASA Glenn whom he hadn’t seen in years. Creager used the opportunity to tell him about the work he was doing in the NASA Glenn Simulated Lunar Operations (SLOPE) Laboratory, which can simulate the surfaces of the Moon and Mars to help scientists test rover performance. He brought Padula to the lab, where Padula immediately took note of the spring tires. At the time, they were made of steel.
Padula remarked, “The minute I saw the tire, I said, aren’t you having problems with those plasticizing?” Plasticizing refers to a metal undergoing deformation that isn’t reversible and can lead to damage or failure of the component.
“Colin told me, ‘That’s the only problem we can’t solve.’” Padula continued, “I said, I have your solution. I’m developing a new alloy that will solve that. And that’s how SMA tires started.”
From there, Padula, Creager, and their teams joined forces to improve NASA’s existing spring tires with a game-changing material: nickel-titanium SMAs. The metal can accommodate deformation despite extreme stress, permitting the tires to return to their original shape even with rigorous impact, which is not possible for spring tires made with conventional metal.
Credit: NASA Since then, research has been abundant, and in the fall of 2024, teams from NASA Glenn traveled to Airbus Defence and Space in Stevenage, United Kingdom, to test NASA’s innovative SMA spring tires. Testing took place at the Airbus Mars Yard — an enclosed facility created to simulate the harsh conditions of Martian terrain.
“We went out there with the team, we brought our motion tracking system and did different tests uphill and back downhill,” Creager said. “We conducted a lot of cross slope tests over rocks and sand where the focus was on understanding stability because this was something we had never tested before.”
During the tests, researchers monitored rovers as the wheels went over rocks, paying close attention to how much the crowns of the tires shifted, any damage, and downhill sliding. The team expected sliding and shifting, but it was very minimal, and testing met all expectations. Researchers also gathered insights about the tires’ stability, maneuverability, and rock traversal capabilities.
As NASA continues to advance systems for deep space exploration, the agency’s Extravehicular Activity and Human Surface Mobility program enlisted Padula to research additional ways to improve the properties of SMAs for future rover tires and other potential uses, including lunar environments.
“My goal is to extend the operating temperature capability of SMAs for applications like tires, and to look at applying these materials for habitat protection,” Padula said. “We need new materials for extreme environments that can provide energy absorption for micrometeorite strikes that happen on the Moon to enable things like habitat structures for large numbers of astronauts and scientists to do work on the Moon and Mars.”
Researchers say shape memory alloy spring tires are just the beginning.
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By NASA
Creating a golden streak in the night sky, a SpaceX Falcon 9 rocket carrying Firefly Aerospace’s Blue Ghost Mission One lander soars upward after liftoff from Launch Complex 39A at NASA’s Kennedy Space Center in Florida on Wednesday, Jan. 15, as part of NASA’s CLPS (Commercial Lunar Payload Services) initiative. The Blue Ghost lander will carry 10 NASA science and technology instruments to the lunar surface to further understand the Moon and help prepare for future human missions.Credit: NASA/Frank Michaux A suite of NASA scientific investigations and technology demonstrations is on its way to our nearest celestial neighbor aboard a commercial spacecraft, where they will provide insights into the Moon’s environment and test technologies to support future astronauts landing safely on the lunar surface under the agency’s Artemis campaign.
Carrying science and tech on Firefly Aerospace’s first CLPS or Commercial Lunar Payload Services flight for NASA, Blue Ghost Mission 1 launched at 1:11 a.m. EST aboard a SpaceX Falcon 9 rocket from Launch Complex 39A at the agency’s Kennedy Space Center in Florida. The company is targeting a lunar landing on Sunday, March 2.
“This mission embodies the bold spirit of NASA’s Artemis campaign – a campaign driven by scientific exploration and discovery,” said NASA Deputy Administrator Pam Melroy. “Each flight we’re part of is vital step in the larger blueprint to establish a responsible, sustained human presence at the Moon, Mars, and beyond. Each scientific instrument and technology demonstration brings us closer to realizing our vision. Congratulations to the NASA, Firefly, and SpaceX teams on this successful launch.”
Once on the Moon, NASA will test and demonstrate lunar drilling technology, regolith (lunar rocks and soil) sample collection capabilities, global navigation satellite system abilities, radiation tolerant computing, and lunar dust mitigation methods. The data captured could also benefit humans on Earth by providing insights into how space weather and other cosmic forces impact our home planet.
“NASA leads the world in space exploration, and American companies are a critical part of bringing humanity back to the Moon,” said Nicola Fox, associate administrator, Science Mission Directorate, NASA Headquarters in Washington. “We learned many lessons during the Apollo Era which informed the technological and science demonstrations aboard Firefly’s Blue Ghost Mission 1 – ensuring the safety and health of our future science instruments, spacecraft, and, most importantly, our astronauts on the lunar surface. I am excited to see the incredible science and technological data Firefly’s Blue Ghost Mission 1 will deliver in the days to come.”
As part of NASA’s modern lunar exploration activities, CLPS deliveries to the Moon will help humanity better understand planetary processes and evolution, search for water and other resources, and support long-term, sustainable human exploration of the Moon in preparation for the first human mission to Mars.
There are 10 NASA payloads flying on this flight:
Lunar Instrumentation for Subsurface Thermal Exploration with Rapidity (LISTER) will characterize heat flow from the interior of the Moon by measuring the thermal gradient and conductivity of the lunar subsurface. It will take several measurements to about a 10-foot final depth using pneumatic drilling technology with a custom heat flow needle instrument at its tip. Lead organization: Texas Tech University Lunar PlanetVac (LPV) is designed to collect regolith samples from the lunar surface using a burst of compressed gas to drive the regolith into a sample chamber for collection and analysis by various instruments. Additional instrumentation will then transmit the results back to Earth. Lead organization: Honeybee Robotics Next Generation Lunar Retroreflector (NGLR) serves as a target for lasers on Earth to precisely measure the distance between Earth and the Moon. The retroreflector that will fly on this mission could also collect data to understand various aspects of the lunar interior and address fundamental physics questions. Lead organization: University of Maryland Regolith Adherence Characterization (RAC) will determine how lunar regolith sticks to a range of materials exposed to the Moon’s environment throughout the lunar day. The RAC instrument will measure accumulation rates of lunar regolith on the surfaces of several materials including solar cells, optical systems, coatings, and sensors through imaging to determine their ability to repel or shed lunar dust. The data captured will allow the industry to test, improve, and protect spacecraft, spacesuits, and habitats from abrasive regolith. Lead organization: Aegis Aerospace Radiation Tolerant Computer (RadPC) will demonstrate a computer that can recover from faults caused by ionizing radiation. Several RadPC prototypes have been tested aboard the International Space Station and Earth-orbiting satellites, but now will demonstrate the computer’s ability to withstand space radiation as it passes through Earth’s radiation belts, while in transit to the Moon, and on the lunar surface. Lead organization: Montana State University Electrodynamic Dust Shield (EDS) is an active dust mitigation technology that uses electric fields to move and prevent hazardous lunar dust accumulation on surfaces. The EDS technology is designed to lift, transport, and remove particles from surfaces with no moving parts. Multiple tests will demonstrate the feasibility of the self-cleaning glasses and thermal radiator surfaces on the Moon. In the event the surfaces do not receive dust during landing, EDS has the capability to re-dust itself using the same technology. Lead organization: NASA’s Kennedy Space Center Lunar Environment heliospheric X-ray Imager (LEXI) will capture a series of X-ray images to study the interaction of solar wind and the Earth’s magnetic field that drives geomagnetic disturbances and storms. Deployed and operated on the lunar surface, this instrument will provide the first global images showing the edge of Earth’s magnetic field for critical insights into how space weather and other cosmic forces surrounding our planet impact it. Lead organizations: NASA’s Goddard Space Flight Center, Boston University, and Johns Hopkins University Lunar Magnetotelluric Sounder (LMS) will characterize the structure and composition of the Moon’s mantle by measuring electric and magnetic fields. This investigation will help determine the Moon’s temperature structure and thermal evolution to understand how the Moon has cooled and chemically differentiated since it formed. Lead organization: Southwest Research Institute Lunar GNSS Receiver Experiment (LuGRE) will demonstrate the possibility of acquiring and tracking signals from Global Navigation Satellite System constellations, specifically GPS and Galileo, during transit to the Moon, during lunar orbit, and on the lunar surface. If successful, LuGRE will be the first pathfinder for future lunar spacecraft to use existing Earth-based navigation constellations to autonomously and accurately estimate their position, velocity, and time. Lead organizations: NASA Goddard, Italian Space Agency Stereo Camera for Lunar Plume-Surface Studies (SCALPSS) will use stereo imaging photogrammetry to capture the impact of rocket plume on lunar regolith as the lander descends on the Moon’s surface. The high-resolution stereo images will aid in creating models to predict lunar regolith erosion, which is an important task as bigger, heavier payloads are delivered to the Moon in close proximity to each other. This instrument also flew on Intuitive Machine’s first CLPS delivery. Lead organization: NASA’s Langley Research Center “With 10 NASA science and technology instruments launching to the Moon, this is the largest CLPS delivery to date, and we are proud of the teams that have gotten us to this point,” said Chris Culbert, program manager for the Commercial Lunar Payload Services initiative at NASA’s Johnson Space Center in Houston. “We will follow this latest CLPS delivery with more in 2025 and later years. American innovation and interest to the Moon continues to grow, and NASA has already awarded 11 CLPS deliveries and plans to continue to select two more flights per year.”
Firefly’s Blue Ghost lander is targeted to land near a volcanic feature called Mons Latreille within Mare Crisium, a more than 300-mile-wide basin located in the northeast quadrant of the Moon’s near side. The NASA science on this flight will gather valuable scientific data studying Earth’s nearest neighbor and helping pave the way for the first Artemis astronauts to explore the lunar surface later this decade.
Learn more about NASA’s CLPS initiative at:
https://www.nasa.gov/clps
-end-
Amber Jacobson / Karen Fox
Headquarters, Washington
202-358-1600
amber.c.jacobson@nasa.gov / karen.c.fox@nasa.gov
Natalia Riusech / Nilufar Ramji
Johnson Space Center, Houston
281-483-5111
nataila.s.riusech@nasa.gov / nilufar.ramji@nasa.gov
Antonia Jaramillo
Kennedy Space Center, Florida
321-501-8425
antonia.jaramillobotero@nasa.gov
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Last Updated Jan 15, 2025 LocationNASA Headquarters Related Terms
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