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By NASA
NASA has selected multiple companies to expand the agency’s Near Space Network’s commercial direct-to-Earth capabilities services, which is a mission-critical communication capability that allows spacecraft to transmit data directly to ground stations on Earth.
The work will be awarded under new Near Space Network services contracts that are firm-fixed-price, indefinite-delivery/indefinite-quantity contracts. Project timelines span from February 2025 to September 2029, with an additional five-year option period that could extend a contract through Sept. 30, 2034. The cumulative maximum value of all Near Space Network Services contracts is $4.82 billion.
Some companies received multiple task orders for subcategories identified in their contracts. Awards are as follows:
Intuitive Machines of Houston will receive two task order awards on its contract for Subcategory 1.2 GEO to Cislunar Direct to Earth (DTE) Services and Subcategory 1.3 xCislunar DTE Services to support NASA’s Lunar Exploration Ground Segment, providing additional capacity to alleviate demand on the Deep Space Network and to meet the mission requirements for unique, highly elliptical orbits. The company also previously received a task order award for Subcategory 2.2 GEO to Cislunar Relay Services. Kongsberg Satellite Services of Tromsø, Norway, will receive two task order awards on its contract for Subcategory 1.1 Earth Proximity DTE and Subcategory 1.2 to support science missions in low Earth orbit and NASA’s Lunar Exploration Ground Segment, providing additional capacity to alleviate demand on the Deep Space Network. SSC Space U.S. Inc. of Horsham, Pennsylvania, will receive two task order awards on its contract for Subcategories 1.1 and 1.3 to support science missions in low Earth orbit and to meet the mission requirements for unique, highly elliptical orbits. Viasat, Inc. of Duluth, Georgia, will be awarded a task order on its contract for Subcategory 1.1 to support science missions in low Earth orbit. The Near Space Network’s direct-to-Earth capability supports many of NASA’s missions ranging from climate studies on Earth to research on celestial objects. It also will play a role in NASA’s Artemis campaign, which calls for long-term exploration of the Moon.
NASA’s goal is to provide users with communication and navigation services that are secure, reliable, and affordable, so that all NASA users receive the services required by their mission within their latency, accuracy, and availability requirements.
These awards demonstrate NASA’s ongoing commitment to fostering strong partnerships with the commercial space sector, which plays an essential role in delivering the communications infrastructure critical to the agency’s science and exploration missions.
As part of the agency’s SCaN (Space Communications and Navigation) Program, teams at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, will carry out the work of the Near Space Network. The Near Space Network provides missions out to 1.2 million miles (2 million kilometers) with communications and navigation services, enabling spacecraft to exchange critical data with mission operators on Earth. Using space relays in geosynchronous orbit and a global system of government and commercial direct-to-Earth antennas on Earth, the network brings down terabytes of data each day.
Learn more about NASA’s Near Space Network:
https://www.nasa.gov/near-space-network
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Joshua Finch
Headquarters, Washington
202-358-1100
joshua.a.finch@nasa.gov
Jeremy Eggers
Goddard Space Flight Center, Greenbelt, Maryland
757-824-2958
jeremy.l.eggers@nasa.gov
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By NASA
NASA’s Dawn spacecraft captured this image of Vesta as it left the giant asteroid’s orbit in 2012. The framing camera was looking down at the north pole, which is in the middle of the image.NASA/JPL-Caltech/UCLA/MPS/DLR/IDA Known as flow formations, these channels could be etched on bodies that would seem inhospitable to liquid because they are exposed to the extreme vacuum conditions of space.
Pocked with craters, the surfaces of many celestial bodies in our solar system provide clear evidence of a 4.6-billion-year battering by meteoroids and other space debris. But on some worlds, including the giant asteroid Vesta that NASA’s Dawn mission explored, the surfaces also contain deep channels, or gullies, whose origins are not fully understood.
A prime hypothesis holds that they formed from dry debris flows driven by geophysical processes, such as meteoroid impacts, and changes in temperature due to Sun exposure. A recent NASA-funded study, however, provides some evidence that impacts on Vesta may have triggered a less-obvious geologic process: sudden and brief flows of water that carved gullies and deposited fans of sediment. By using lab equipment to mimic conditions on Vesta, the study, which appeared in Planetary Science Journal, detailed for the first time what the liquid could be made of and how long it would flow before freezing.
Although the existence of frozen brine deposits on Vesta is unconfirmed, scientists have previously hypothesized that meteoroid impacts could have exposed and melted ice that lay under the surface of worlds like Vesta. In that scenario, flows resulting from this process could have etched gullies and other surface features that resemble those on Earth.
To explore potential explanations for deep channels, or gullies, seen on Vesta, scientists used JPL’s Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE, to simulate conditions on the giant asteroid that would occur after meteoroids strike the surface.NASA/JPL-Caltech But how could airless worlds — celestial bodies without atmospheres and exposed to the intense vacuum of space — host liquids on the surface long enough for them to flow? Such a process would run contrary to the understanding that liquids quickly destabilize in a vacuum, changing to a gas when the pressure drops.
“Not only do impacts trigger a flow of liquid on the surface, the liquids are active long enough to create specific surface features,” said project leader and planetary scientist Jennifer Scully of NASA’s Jet Propulsion Laboratory in Southern California, where the experiments were conducted. “But for how long? Most liquids become unstable quickly on these airless bodies, where the vacuum of space is unyielding.”
The critical component turns out to be sodium chloride — table salt. The experiments found that in conditions like those on Vesta, pure water froze almost instantly, while briny liquids stayed fluid for at least an hour. “That’s long enough to form the flow-associated features identified on Vesta, which were estimated to require up to a half-hour,” said lead author Michael J. Poston of the Southwest Research Institute in San Antonio.
Launched in 2007, the Dawn spacecraft traveled to the main asteroid belt between Mars and Jupiter to orbit Vesta for 14 months and Ceres for almost four years. Before ending in 2018, the mission uncovered evidence that Ceres had been home to a subsurface reservoir of brine and may still be transferring brines from its interior to the surface. The recent research offers insights into processes on Ceres but focuses on Vesta, where ice and salts may produce briny liquid when heated by an impact, scientists said.
Re-creating Vesta
To re-create Vesta-like conditions that would occur after a meteoroid impact, the scientists relied on a test chamber at JPL called the Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE. By rapidly reducing the air pressure surrounding samples of liquid, they mimicked the environment around fluid that comes to the surface. Exposed to vacuum conditions, pure water froze instantly. But salty fluids hung around longer, continuing to flow before freezing.
The brines they experimented with were a little over an inch (a few centimeters) deep; scientists concluded the flows on Vesta that are yards to tens of yards deep would take even longer to refreeze.
The researchers were also able to re-create the “lids” of frozen material thought to form on brines. Essentially a frozen top layer, the lids stabilize the liquid beneath them, protecting it from being exposed to the vacuum of space — or, in this case the vacuum of the DUSTIE chamber — and helping the liquid flow longer before freezing again.
This phenomenon is similar to how on Earth lava flows farther in lava tubes than when exposed to cool surface temperatures. It also matches up with modeling research conducted around potential mud volcanoes on Mars and volcanoes that may have spewed icy material from volcanoes on Jupiter’s moon Europa.
“Our results contribute to a growing body of work that uses lab experiments to understand how long liquids last on a variety of worlds,” Scully said.
Find more information about NASA’s Dawn mission here:
https://science.nasa.gov/mission/dawn/
News Media Contacts
Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif.
818-287-4115
gretchen.p.mccartney@jpl.nasa.gov
Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
2024-178
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Last Updated Dec 20, 2024 Related Terms
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By USH
While observing the Orion Nebula with his 12-inch Dobsonian telescope, a sky-watcher noticed an unusual flashing object. As stars appeared to drift due to Earth's rotation, this particular object while flashing approximately every 20 seconds clearly travels through deep space.
The observer wonders whether it might be a rotating satellite or not. However, this isn’t the first sighting of cigar-shaped UFOs or other mysterious objects traveling through space near the Orion Nebula, so it is quite possible that it could be an interstellar craft.
Over the years, I have shared several articles, complete with images and videos, documenting similar UFO sightings around the Orion Nebula. You can explore these under the tag: Orion Nebula.
Interestingly, these sightings have all occurred between November and February, suggesting there may be a seasonal pattern to these observations.
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By NASA
4 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
The Permafrost Tunnel north of Fairbanks, Alaska, was dug in the 1960s and is run by the U.S. Army’s Cold Regions Research and Engineering Laboratory. It is the site of much research into permafrost — ground that stays frozen throughout the year, for multiple years.NASA/Kate Ramsayer Earth’s far northern reaches have locked carbon underground for millennia. New research paints a picture of a landscape in change.
A new study, co-authored by NASA scientists, details where and how greenhouse gases are escaping from the Earth’s vast northern permafrost region as the Arctic warms. The frozen soils encircling the Arctic from Alaska to Canada to Siberia store twice as much carbon as currently resides in the atmosphere — hundreds of billions of tons — and most of it has been buried for centuries.
An international team, led by researchers at Stockholm University, found that from 2000 to 2020, carbon dioxide uptake by the land was largely offset by emissions from it. Overall, they concluded that the region has been a net contributor to global warming in recent decades in large part because of another greenhouse gas, methane, that is shorter-lived but traps significantly more heat per molecule than carbon dioxide.
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Greenhouse gases shroud the globe in this animation showing data from 2021. Carbon dioxide is shown in orange; methane is shown in purple. Methane traps heat 28 times more effectively than carbon dioxide over a 100-year timescale. Wetlands are a significant source of such emissions.NASA’s Scientific Visualization Studio The findings reveal a landscape in flux, said Abhishek Chatterjee, a co-author and scientist at NASA’s Jet Propulsion Laboratory in Southern California. “We know that the permafrost region has captured and stored carbon for tens of thousands of years,” he said. “But what we are finding now is that climate-driven changes are tipping the balance toward permafrost being a net source of greenhouse gas emissions.”
Carbon Stockpile
Permafrost is ground that has been permanently frozen for anywhere from two years to hundreds of thousands of years. A core of it reveals thick layers of icy soils enriched with dead plant and animal matter that can be dated using radiocarbon and other techniques. When permafrost thaws and decomposes, microbes feed on this organic carbon, releasing some of it as greenhouse gases.
Unlocking a fraction of the carbon stored in permafrost could further fuel climate change. Temperatures in the Arctic are already warming two to four times faster than the global average, and scientists are learning how thawing permafrost is shifting the region from being a net sink for greenhouse gases to becoming a net source of warming.
They’ve tracked emissions using ground-based instruments, aircraft, and satellites. One such campaign, NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE), is focused on Alaska and western Canada. Yet locating and measuring emissions across the far northern fringes of Earth remains challenging. One obstacle is the vast scale and diversity of the environment, composed of evergreen forests, sprawling tundra, and waterways.
This map, based on data provided by the National Snow and Ice Data Center, shows the extent of Arctic permafrost. The amount of permafrost underlying the surface ranges from continuous — in the coldest areas — to more isolated and sporadic patches.NASA Earth Observatory Cracks in the Sink
The new study was undertaken as part of the Global Carbon Project’s RECCAP-2 effort, which brings together different science teams, tools, and datasets to assess regional carbon balances every few years. The authors followed the trail of three greenhouse gases — carbon dioxide, methane, and nitrous oxide — across 7 million square miles (18 million square kilometers) of permafrost terrain from 2000 to 2020.
Researchers found the region, especially the forests, took up a fraction more carbon dioxide than it released. This uptake was largely offset by carbon dioxide emitted from lakes and rivers, as well as from fires that burned both forest and tundra.
They also found that the region’s lakes and wetlands were strong sources of methane during those two decades. Their waterlogged soils are low in oxygen while containing large volumes of dead vegetation and animal matter — ripe conditions for hungry microbes. Compared to carbon dioxide, methane can drive significant climate warming in short timescales before breaking down relatively quickly. Methane’s lifespan in the atmosphere is about 10 years, whereas carbon dioxide can last hundreds of years.
The findings suggest the net change in greenhouse gases helped warm the planet over the 20-year period. But over a 100-year period, emissions and absorptions would mostly cancel each other out. In other words, the region teeters from carbon source to weak sink. The authors noted that events such as extreme wildfires and heat waves are major sources of uncertainty when projecting into the future.
Bottom Up, Top Down
The scientists used two main strategies to tally greenhouse gas emissions from the region. “Bottom-up” methods estimate emissions from ground- and air-based measurements and ecosystem models. Top-down methods use atmospheric measurements taken directly from satellite sensors, including those on NASA’s Orbiting Carbon Observatory-2 (OCO-2) and JAXA’s (Japan Aerospace Exploration Agency)Greenhouse Gases Observing Satellite.
Regarding near-term, 20-year, global warming potential, both scientific approaches aligned on the big picture but differed in magnitude: The bottom-up calculations indicated significantly more warming.
“This study is one of the first where we are able to integrate different methods and datasets to put together this very comprehensive greenhouse gas budget into one report,” Chatterjee said. “It reveals a very complex picture.”
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
Written by Sally Younger
2024-147
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Last Updated Oct 29, 2024 Related Terms
Earth Carbon Cycle Climate Change Greenhouse Gases Jet Propulsion Laboratory Explore More
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