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By Space Force
The Space Force Year in Review is a collection of photos that showcase the men and women of the U.S. Space Force participating in activities and operations necessary to develop and protect U.S. interests in space.
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By Space Force
The Space Force Year in Review is a collection of photos that showcase the men and women of the U.S. Space Force participating in activities and operations necessary to develop and protect U.S. interests in space.
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By NASA
Modular Assembled Radiators for Nuclear Electric Propulsion Vehicles, or MARVL, aims to take a critical element of nuclear electric propulsion, its heat dissipation system, and divide it into smaller components that can be assembled robotically and autonomously in space. This is an artist’s rendering of what the fully assembled system might look like.NASA The trip to Mars and back is not one for the faint of heart. We’re not talking days, weeks, or months. But there are technologies that could help transport a crew on that round-trip journey in a relatively quick two years.
One option NASA is exploring is nuclear electric propulsion, which employs a nuclear reactor to generate electricity that ionizes, or positively charges, and electrically accelerates gaseous propellants to provide thrust to a spacecraft.
Researchers at NASA’s Langley Research Center in Hampton, Virginia, are working on a system that could help bring nuclear electric propulsion one significant, technology-defining step closer to reality.
Modular Assembled Radiators for Nuclear Electric Propulsion Vehicles, or MARVL, aims to take a critical element of nuclear electric propulsion, its heat dissipation system, and divide it into smaller components that can be assembled robotically and autonomously in space.
“By doing that, we eliminate trying to fit the whole system into one rocket fairing,” said Amanda Stark, a heat transfer engineer at NASA Langley and the principal investigator for MARVL. “In turn, that allows us to loosen up the design a little bit and really optimize it.”
Loosening up the design is key, because as Stark mentioned, previous ideas called for fitting the entire nuclear electric radiator system under a rocket fairing, or nose cone, which covers and protects a payload. Fully deployed, the heat dissipating radiator array would be roughly the size of a football field. You can imagine the challenge engineers would face in getting such a massive system folded up neatly inside the tip of a rocket.
The MARVL technology opens a world of possibilities. Rather than cram the whole system into an existing rocket, this would allow researchers the flexibility to send pieces of the system to space in whatever way would make the most sense, then have it all assembled off the planet.
Once in space, robots would connect the nuclear electric propulsion system’s radiator panels, through which a liquid metal coolant, such as a sodium-potassium alloy, would flow.
While this is still an engineering challenge, it is exactly the kind of engineering challenge in-space-assembly experts at NASA Langley have been working on for decades. The MARVL technology could mark a significant first milestone. Rather than being an add-on to an existing technology, the in-space assembly component will benefit and influence the design of the very spacecraft it would serve.
“Existing vehicles have not previously considered in-space assembly during the design process, so we have the opportunity here to say, ‘We’re going to build this vehicle in space. How do we do it? And what does the vehicle look like if we do that?’ I think it’s going to expand what we think of when it comes to nuclear propulsion,” said Julia Cline, a mentor for the project in NASA Langley’s Research Directorate, who led the center’s participation in the Nuclear Electric Propulsion tech maturation plan development as a precursor to MARVL. That tech maturation plan was run out of the agency’s Space Nuclear Propulsion project at Marshall Space Flight Center in Huntsville, Alabama.
NASA’s Space Technology Mission Directorate awarded the MARVL project through the Early Career Initiative, giving the team two years to advance the concept. Stark and her teammates are working with an external partner, Boyd Lancaster, Inc., to develop the thermal management system. The team also includes radiator design engineers from NASA’s Glenn Research Center in Cleveland and fluid engineers from NASA’s Kennedy Space Center in Florida. After two years, the team hopes to move the MARVL design to a small-scale ground demonstration.
The idea of robotically building a nuclear propulsion system in space is sparking imaginations.
“One of our mentors remarked, ‘This is why I wanted to work at NASA, for projects like this,’” said Stark, “which is awesome because I am so happy to be involved with it, and I feel the same way.”
Additional support for MARVL comes from the agency’s Space Nuclear Propulsion project. The project’s ongoing effort is maturing technologies for operations around the Moon and near-Earth exploration, deep space science missions, and human exploration using nuclear electric propulsion and nuclear thermal propulsion.
An artist’s rendering that shows the different components of a fully assembled nuclear electric propulsion system.NASAView the full article
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By NASA
This map of Earth in 2024 shows global surface temperature anomalies, or how much warmer or cooler each region of the planet was compared to the average from 1951 to 1980. Normal temperatures are shown in white, higher-than-normal temperatures in red and orange, and lower-than-normal temperatures in blue. An animated version of this map shows global temperature anomalies changing over time, dating back to 1880. Download this visualization from NASA Goddard’s Scientific Visualization Studio: https://svs.gsfc.nasa.gov/5450. Credit: NASA’s Scientific Visualization Studio Earth’s average surface temperature in 2024 was the warmest on record, according to an analysis led by NASA scientists.
Global temperatures in 2024 were 2.30 degrees Fahrenheit (1.28 degrees Celsius) above the agency’s 20th-century baseline (1951-1980), which tops the record set in 2023. The new record comes after 15 consecutive months (June 2023 through August 2024) of monthly temperature records — an unprecedented heat streak.
“Once again, the temperature record has been shattered — 2024 was the hottest year since record keeping began in 1880,” said NASA Administrator Bill Nelson. “Between record breaking temperatures and wildfires currently threatening our centers and workforce in California, it has never been more important to understand our changing planet.”
NASA scientists further estimate Earth in 2024 was about 2.65 degrees Fahrenheit (1.47 degrees Celsius) warmer than the mid-19th century average (1850-1900). For more than half of 2024, average temperatures were more than 1.5 degrees Celsius above the baseline, and the annual average, with mathematical uncertainties, may have exceeded the level for the first time.
“The Paris Agreement on climate change sets forth efforts to remain below 1.5 degrees Celsius over the long term. To put that in perspective, temperatures during the warm periods on Earth three million years ago — when sea levels were dozens of feet higher than today — were only around 3 degrees Celsius warmer than pre-industrial levels,” said Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies (GISS) in New York. “We are halfway to Pliocene-level warmth in just 150 years.”
Scientists have concluded the warming trend of recent decades is driven by heat-trapping carbon dioxide, methane, and other greenhouse gases. In 2022 and 2023, Earth saw record increases in carbon dioxide emissions from fossil fuels, according to a recent international analysis. The concentration of carbon dioxide in the atmosphere has increased from pre-industrial levels in the 18th century of approximately 278 parts per million to about 420 parts per million today.
NASA and other federal agencies regularly collect data on greenhouse gas concentrations and emissions. These data are available at the U.S. Greenhouse Gas Center, a multi-agency effort that consolidates information from observations and models, with a goal of providing decision-makers with one location for data and analysis.
Exceptional heat trends
The temperatures of individual years can be influenced by natural climate fluctuations such as El Niño and La Niña, which alternately warm and cool the tropical Pacific Ocean. The strong El Niño that began in fall 2023 helped nudge global temperatures above previous records.
The heat surge that began in 2023 continued to exceed expectations in 2024, Schmidt said, even though El Niño abated. Researchers are working to identify contributing factors, including possible climate impacts of the January 2022 Tonga volcanic eruption and reductions in pollution, which may change cloud cover and how solar energy is reflected back into space.
“Not every year is going to break records, but the long-term trend is clear,” Schmidt said. “We’re already seeing the impact in extreme rainfall, heat waves, and increased flood risk, which are going to keep getting worse as long as emissions continue.”
Seeing changes locally
NASA assembles its temperature record using surface air temperature data collected from tens of thousands of meteorological stations, as well as sea surface temperature data acquired by ship- and buoy-based instruments. This data is analyzed using methods that account for the varied spacing of temperature stations around the globe and for urban heating effects that could skew the calculations.
A new assessment published earlier this year by scientists at the Colorado School of Mines, National Science Foundation, the National Atmospheric and Oceanic Administration (NOAA), and NASA further increases confidence in the agency’s global and regional temperature data.
“When changes happen in the climate, you see it first in the global mean, then you see it at the continental scale and then at the regional scale. Now, we’re seeing it at the local level,” Schmidt said. “The changes occurring in people’s everyday weather experiences have become abundantly clear.”
Independent analyses by NOAA, Berkeley Earth, the Hadley Centre (part of the United Kingdom’s weather forecasting Met Office) and Copernicus Climate Services in Europe have also concluded that the global surface temperatures for 2024 were the highest since modern record-keeping began. These scientists use much of the same temperature data in their analyses but use different methodologies and models. Each shows the same ongoing warming trend.
NASA’s full dataset of global surface temperatures, as well as details of how NASA scientists conducted the analysis, are publicly available from GISS, a NASA laboratory managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland.
For more information about NASA’s Earth science programs, visit:
https://www.nasa.gov/earth
-end-
Liz Vlock
Headquarters, Washington
202-358-1600
elizabeth.a.vlock@nasa.gov
Peter Jacobs
Goddard Space Flight Center, Greenbelt, Md.
301-286-0535
peter.jacobs@nasa.gov
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By NASA
Hubble Space Telescope Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Hubble News Archive Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Glossary Posters Hubble on the NASA App More 35th Anniversary 2 min read
Hubble Rings In the New Year
ESA/Hubble, NASA, and D. Erb This NASA/ESA Hubble Space Telescope image reveals a tiny patch of sky in the constellation Hydra. The stars and galaxies depicted here span a mind-bending range of distances. The objects in this image that are nearest to us are stars within our own Milky Way galaxy. You can easily spot these stars by their diffraction spikes, lines that radiate from bright light sources, like nearby stars, as a result of how that light interacts with Hubble’s secondary mirror supports. The bright star that sits just at the edge of the prominent bluish galaxy is only 3,230 light-years away, as measured by ESA’s Gaia space observatory.
Behind this star is a galaxy named LEDA 803211. At 622 million light-years distant, this galaxy is close enough that its bright galactic nucleus is clearly visible, as are numerous star clusters scattered around its patchy disk. Many of the more distant galaxies in this frame appear star-like, with no discernible structure, but without the diffraction spikes of a star in our galaxy.
Of all the galaxies in this frame, one pair stands out: a smooth golden galaxy encircled by a nearly complete ring in the upper-right corner of the image. This curious configuration is the result of gravitational lensing that warps and magnifies the light of distant objects. Einstein predicted the curving of spacetime by matter in his general theory of relativity, and galaxies seemingly stretched into rings like the one in this image are called Einstein rings.
The lensed galaxy, whose image we see as the ring, lies incredibly far away from Earth: we are seeing it as it was when the universe was just 2.5 billion years old. The galaxy acting as the gravitational lens itself is likely much closer. A nearly perfect alignment of the two galaxies is necessary to give us this rare kind of glimpse into galactic life in the early days of the universe.
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Hubble’s Gravitational Lenses
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
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Last Updated Jan 10, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
Astrophysics Astrophysics Division Elliptical Galaxies Galaxies Goddard Space Flight Center Gravitational Lensing Hubble Space Telescope Spiral Galaxies The Universe Keep Exploring Discover More Topics From NASA
Hubble Space Telescope
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
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