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By NASA
Due to launch in the early 2030s, NASA’s DAVINCI mission will investigate whether Venus — a sweltering world wrapped in an atmosphere of noxious gases — once had oceans and continents like Earth.
Consisting of a flyby spacecraft and descent probe, DAVINCI will focus on a mountainous region called Alpha Regio, a possible ancient continent. Though a handful of international spacecraft plunged through Venus’ atmosphere between 1970 and 1985, DAVINCI’s probe will be the first to capture images of this intriguing terrain ever taken from below Venus’ thick and opaque clouds.
But how does a team prepare for a mission to a planet that hasn’t seen an atmospheric probe in nearly 50 years, and that tends to crush or melt its spacecraft visitors?
Scientists leading the DAVINCI mission started by using modern data-analysis techniques to pore over decades-old data from previous Venus missions. Their goal is to arrive at our neighboring planet with as much detail as possible. This will allow scientists to most effectively use the probe’s descent time to collect new information that can help answer longstanding questions about Venus’ evolutionary path and why it diverged drastically from Earth’s.
On the left, a new and more detailed view of Venus’ Alpha Regio region developed by scientists on NASA’s DAVINCI mission to Venus, due to launch in the early 2030s. On the right is a less detailed map created using radar altimeter data collected by NASA’s Magellan spacecraft in the early 1990s. The colors on the maps depict topography, with dark blues identifying low elevations and browns identifying high elevations. To make the map on the left, the DAVINCI science team re-analyzed Magellan data and supplemented it with radar data collected on three occasions from the Arecibo Observatory in Puerto Rico, and used machine vision computer models to scrutinize the data and fill in gaps in information. The red ellipses on each image mark the area DAVINCI’s probe will descend over as it collects data on its way toward the surface. Jim Garvin/NASA’s Goddard Space Flight Center Between 1990 and 1994, NASA’s Magellan spacecraft used radar imaging and altimetry to map the topography of Alpha Regio from Venus’ orbit. Recently, NASA’s DAVINICI’s team sought more detail from these maps, so scientists applied new techniques to analyze Magellan’s radar altimeter data. They then supplemented this data with radar images taken on three occasions from the former Arecibo Observatory in Puerto Rico and used machine vision computer models to scrutinize the data and fill in gaps in information at new scales (less than 0.6 miles, or 1 kilometer).
As a result, scientists improved the resolution of Alpha Regio maps tenfold, predicting new geologic patterns on the surface and prompting questions about how these patterns could have formed in Alpha Regio’s mountains.
Benefits of Looking Backward
Old data offers many benefits to new missions, including information about what frequencies, parts of spectrum, or particle sizes earlier instruments covered so that new instruments can fill in the gaps.
At NASA Space Science Data Coordinated Archive, which is managed out of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, staff restore and digitize data from old spacecraft. That vintage data, when compared with modern observations, can show how a planet changes over time, and can even lead to new discoveries long after missions end. Thanks to new looks at Magellan observations, for instance, scientists recently found evidence of modern-day volcanic activity on Venus.
The three images in this carousel were taken in March 2024 at NASA Space Science Data Coordinated Archive at NASA’s Goddard Space Flight Center in Greenbelt, Md. The first shows stacked boxes of microfilm with data from Apollo missions. The middle image shows miniaturized records from NASA’s 1964 Mariner 4 flyby mission to Mars. And the final image shows a view of Jupiter from NASA’s Pioneer 10 flyby mission to the outer planets, which launched on March 2, 1972. The three images in this carousel were taken in March 2024 at NASA Space Science Data Coordinated Archive at NASA’s Goddard Space Flight Center in Greenbelt, Md. The first shows stacked boxes of microfilm with data from Apollo missions. The middle image shows miniaturized records from NASA’s 1964 Mariner 4 flyby mission to Mars. And the final image shows a view of Jupiter from NASA’s Pioneer 10 flyby mission to the outer planets, which launched on March 2, 1972. The three images in this carousel were taken in March 2024 at NASA Space Science Data Coordinated Archive at NASA’s Goddard Space Flight Center in Greenbelt, Md. The first shows stacked boxes of microfilm with data from Apollo missions. The middle image shows miniaturized records from NASA’s 1964 Mariner 4 flyby mission to Mars. And the final image shows a view of Jupiter from NASA’s Pioneer 10 flyby mission to the outer planets, which launched on March 2, 1972.
Magellan was among the first missions to be digitally archived in NASA’s publicly accessible online repository of planetary mission data. But the agency has reams of data — much of it not yet digitized — dating back to 1958, when the U.S. launched its first satellite, Explorer 1.
Data restoration is a complex and resource-intensive job, and NASA prioritizes digitizing data that scientists need. With three forthcoming missions to Venus — NASA’s DAVINCI and VERITAS, plus ESA’s (European Space Agency) Envision — space data archive staff are helping scientists access data from Pioneer Venus, NASA’s last mission to drop probes into Venus’ atmosphere in 1978.
Mosaic of Venus
Alpha Regio is one of the most mysterious spots on Venus. Its terrain, known as “tessera,” is similar in appearance to rugged Earth mountains, but more irregular and disorderly.
So called because they resemble a geometric parquet floor pattern, tesserae have been found only on Venus, and DAVINCI will be the first mission to explore such terrain in detail and to map its topography.
DAVINCI’s probe will begin photographing Alpha Regio — collecting the highest-resolution images yet — once it descends below the planet’s clouds, starting at about 25 miles, or 40 kilometers, altitude. But even there, gases in the atmosphere scatter light, as does the surface, such that these images will appear blurred.
Could Venus once have been a habitable world with liquid water oceans — like Earth? This is one of the many mysteries associated with our shrouded sister world. Credit: NASA’s Goddard Space Flight Center DAVINCI scientists are working on a solution. Recently, scientists re-analyzed old Venus imaging data using a new artificial-intelligence technique that can sharpen the images and use them to compute three-dimensional topographic maps. This technique ultimately will help the team optimize DAVINCI’s images and maps of Alpha Regio’s mountains. The upgraded images will give scientists the most detailed view ever — down to a resolution of 3 feet, or nearly 1 meter, per pixel — possibly allowing them to detect small features such as rocks, rivers, and gullies for the first time in history.
“All this old mission data is part of a mosaic that tells the story of Venus,” said Jim Garvin, DAVINCI principal investigator and chief scientist at NASA Goddard. “A story that is a masterpiece in the making but incomplete.”
By analyzing the surface texture and rock types at Alpha Regio, scientists hope to determine if Venusian tesserae formed through the same processes that create mountains and certain volcanoes on Earth.
By Lonnie Shekhtman
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Get to know Venus
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Last Updated Oct 17, 2024 Editor Lonnie Shekhtman Contact Lonnie Shekhtman lonnie.shekhtman@nasa.gov Location Goddard Space Flight Center Related Terms
DAVINCI (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging) Pioneer Venus Planetary Science Planetary Science Division Planets Science & Research Science Mission Directorate The Solar System Venus VERITAS (Venus Emissivity, Radio Science, InSAR, Topography & Spectroscopy) View the full article
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By European Space Agency
At the International Astronautical Congress (IAC) in Milan this week, ESA signed a contract for Element #1, the first phase of the HydRON Demonstration System. HydRON, which stands for High thRoughput Optical Network, is set to transform the way data-collecting satellites communicate, using laser technology that will allow satellites to connect with each other and ground networks much faster.
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By Space Force
Delta 8 recently partnered with the JCO cell integrate Space Cockpit-customized dashboards into their COP on their operations floors providing them a tailored approach to domain awareness and to set specific alert parameters to bring their attention quickly to an asset that may be at risk.
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By NASA
5 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
Pacific Island nations such as Kiribati — a low-lying country in the southern Pacific Ocean — are preparing now for a future of higher sea levels.NASA Earth Observatory Climate change is rapidly reshaping a region of the world that’s home to millions of people.
In the next 30 years, Pacific Island nations such as Tuvalu, Kiribati, and Fiji will experience at least 8 inches (15 centimeters) of sea level rise, according to an analysis by NASA’s sea level change science team. This amount of rise will occur regardless of whether greenhouse gas emissions change in the coming years.
The sea level change team undertook the analysis of this region at the request of several Pacific Island nations, including Tuvalu and Kiribati, and in close coordination with the U.S. Department of State.
In addition to the overall analysis, the agency’s sea level team produced high-resolution maps showing which areas of different Pacific Island nations will be vulnerable to high-tide flooding — otherwise known as nuisance flooding or sunny day flooding — by the 2050s. Released on Sept. 23, the maps outline flooding potential in a range of emissions scenarios, from best-case to business-as-usual to worst-case.
“Sea level will continue to rise for centuries, causing more frequent flooding,” said Nadya Vinogradova Shiffer, who directs ocean physics programs for NASA’s Earth Science Division. “NASA’s new flood tool tells you what the potential increase in flooding frequency and severity look like in the next decades for the coastal communities of the Pacific Island nations.”
Team members, led by researchers at the University of Hawaii and in collaboration with scientists at the University of Colorado and Virginia Tech, started with flood maps of Kiribati, Tuvalu, Fiji, Nauru, and Niue. They plan to build high-resolution maps for other Pacific Island nations in the near future. The maps can assist Pacific Island nations in deciding where to focus mitigation efforts.
“Science and data can help the community of Tuvalu in relaying accurate sea level rise projections,” said Grace Malie, a youth leader from Tuvalu who is involved with the Rising Nations Initiative, a United Nations-supported program led by Pacific Island nations to help preserve their statehood and protect the rights and heritage of populations affected by climate change. “This will also help with early warning systems, which is something that our country is focusing on at the moment.”
Future Flooding
The analysis by the sea level change team also found that the number of high-tide flooding days in an average year will increase by an order of magnitude for nearly all Pacific Island nations by the 2050s. Portions of the NASA team’s analysis were included in a sea level rise report published by the United Nations in August 2024.
Areas of Tuvalu that currently see less than five high-tide flood days a year could average 25 flood days annually by the 2050s. Regions of Kiribati that see fewer than five flood days a year today will experience an average of 65 flood days annually by the 2050s.
“I am living the reality of climate change,” said Malie. “Everyone (in Tuvalu) lives by the coast or along the coastline, so everyone gets heavily affected by this.”
Flooding on island nations can come from the ocean inundating land during storms or during exceptionally high tides, called king tides. But it can also result when saltwater intrudes into underground areas and pushes the water table to the surface. “There are points on the island where we will see seawater bubbling from beneath the surface and heavily flooding the area,” Malie added.
Matter of Location
Sea level rise doesn’t occur uniformly around the world. A combination of global and local conditions, such as the topography of a coastline and how glacial meltwater is distributed in the ocean, affects the amount of rise a particular region will experience.
“We’re always focused on the differences in sea level rise from one region to another, but in the Pacific, the numbers are surprisingly consistent,” said Ben Hamlington, a sea level researcher at NASA’s Jet Propulsion Laboratory in Southern California and the agency’s sea level change science team lead.
The impacts of 8 inches (15 centimeters) of sea level rise will vary from country to country. For instance, some nations could experience nuisance flooding several times a year at their airport, while others might face frequent neighborhood flooding equivalent to being inundated for nearly half the year.
Researchers would like to combine satellite data on ocean levels with ground-based measurements of sea levels at specific points, as well as with better land elevation information. “But there’s a real lack of on-the-ground data in these countries,” said Hamlington. The combination of space-based and ground-based measurements can yield more precise sea level rise projections and improved understanding of the impacts to countries in the Pacific.
“The future of the young people of Tuvalu is already at stake,” said Malie. “Climate change is more than an environmental crisis. It is about justice, survival for nations like Tuvalu, and global responsibility.”
To explore the high-tide flooding maps for Pacific Island nations, go to:
https://sealevel.nasa.gov
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
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Last Updated Sep 25, 2024 Related Terms
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
This image, taken from a data visualization, shows Arctic sea ice minimum extent on September 11, 2024. The yellow boundary shows the minimum extent averaged over the 30-year period from 1981 to 2010. Download high-resolution video and images from NASA’s Scientific Visualization Studio: https://svsdev.gsfc.nasa.gov/5382NASA’s Scientific Visualization Studio/Trent L. Schindler Arctic sea ice retreated to near-historic lows in the Northern Hemisphere this summer, likely melting to its minimum extent for the year on Sept.11, 2024, according to researchers at NASA and the National Snow and Ice Data Center (NSIDC). The decline continues the decades-long trend of shrinking and thinning ice cover in the Arctic Ocean.
The amount of frozen seawater in the Arctic fluctuates during the year as the ice thaws and regrows between seasons. Scientists chart these swings to construct a picture of how the Arctic responds over time to rising air and sea temperatures and longer melting seasons. Over the past 46 years, satellites have observed persistent trends of more melting in the summer and less ice formation in winter.
This summer, Arctic sea ice decreased to a its minimum extent on September 11, 2024. According to the National Snow and Ice Data Center this is the 7th lowest in the satellite record). The decline continues the long-term trend of shrinking ice cover in the Arctic Ocean.
Credit: NASA’s Goddard Space Flight Center Tracking sea ice changes in real time has revealed wide-ranging impacts, from losses and changes in polar wildlife habitat to impacts on local communities in the Arctic and international trade routes.
This year, Arctic sea ice shrank to a minimal extent of 1.65 million square miles (4.28 million square kilometers). That’s about 750,000 square miles (1.94 million square kilometers) below the 1981 to 2010 end-of-summer average of 2.4 million square miles (6.22 million square kilometers). The difference in ice cover spans an area larger than the state of Alaska. Sea ice extent is defined as the total area of the ocean with at least 15% ice concentration.
Seventh-Lowest in Satellite Record
This year’s minimum remained above the all-time low of 1.31 million square miles (3.39 million square kilometers) set in September 2012. While sea ice coverage can fluctuate from year to year, it has trended downward since the start of the satellite record for ice in the late 1970s. Since then, the loss of sea ice has been about 30,000 square miles (77,800 square kilometers) per year, according to NSIDC.
Scientists currently measure sea ice extent using data from passive microwave sensors aboard satellites in the Defense Meteorological Satellite Program, with additional historical data from the Nimbus-7 satellite, jointly operated by NASA and the National Oceanic and Atmospheric Administration (NOAA).
Today, the overwhelming majority of ice in the Arctic Ocean is thinner, first-year ice, which is less able to survive the warmer months. There is far, far less ice that is three years or older now,
Nathan Kurtz
Chief, NASA's Cryospheric Sciences Laboratory
Sea ice is not only shrinking, it’s getting younger, noted Nathan Kurtz, lab chief of NASA’s Cryospheric Sciences Laboratory at the agency’s Goddard Space Flight Center in Greenbelt, Maryland.
“Today, the overwhelming majority of ice in the Arctic Ocean is thinner, first-year ice, which is less able to survive the warmer months. There is far, far less ice that is three years or older now,” Kurtz said.
Ice thickness measurements collected with spaceborne altimeters, including NASA’s ICESat and ICESat-2 satellites, have found that much of the oldest, thickest ice has already been lost. New research out of NASA’s Jet Propulsion Laboratory in Southern California shows that in the central Arctic, away from the coasts, fall sea ice now hovers around 4.2 feet (1.3 meters) thick, down from a peak of 8.8 feet (2.7 meters) in 1980.
Another Meager Winter Around Antarctica
Sea ice in the southern polar regions of the planet was also low in 2024. Around Antarctica, scientists are tracking near record-low sea ice at a time when it should have been growing extensively during the Southern Hemisphere’s darkest and coldest months.
Ice around the continent is on track to be just over 6.6 million square miles (16.96 million square kilometers). The average maximum extent between 1981 and 2010 was 7.22 million square miles (18.71 million square kilometers).
The meager growth so far in 2024 prolongs a recent downward trend. Prior to 2014, sea ice in the Antarctic was increasing slightly by about 1% per decade. Following a spike in 2014, ice growth has fallen dramatically. Scientists are working to understand the cause of this reversal. The recurring loss hints at a long-term shift in conditions in the Southern Ocean, likely resulting from global climate change.
“While changes in sea ice have been dramatic in the Arctic over several decades, Antarctic sea ice was relatively stable. But that has changed,” said Walt Meier, a sea ice scientist at NSIDC. “It appears that global warming has come to the Southern Ocean.”
In both the Arctic and Antarctic, ice loss compounds ice loss. This is due to the fact that while bright sea ice reflects most of the Sun’s energy back to space, open ocean water absorbs 90% of it. With more of the ocean exposed to sunlight, water temperatures rise, further delaying sea ice growth. This cycle of reinforced warming is called ice-albedo feedback.
Overall, the loss of sea ice increases heat in the Arctic, where temperatures have risen about four times the global average, Kurtz said.
About the Author
Sally Younger
Senior Science Writer
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Last Updated Sep 24, 2024 LocationGoddard Space Flight Center Related Terms
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