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By European Space Agency
Image: With the festive season approaching, even Earth-observing satellites are getting into the spirit, capturing a stunning compilation of European cities that resemble stars. View the full article
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By NASA
5 Min Read NASA DAVINCI Mission’s Many ‘Firsts’ to Unlock Venus’ Hidden Secrets
The surface of Venus is an inferno with temperatures hot enough to melt lead. This image is a composite of data from NASA’s Magellan spacecraft and Pioneer Venus Orbiter. Credits:
NASA/JPL-Caltech NASA’s DAVINCI — Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging — mission embodies the spirit of innovation and exploration that its namesake, Leonardo da Vinci, was famous for.
Scheduled to launch in the early 2030s, DAVINCI will explore Venus with both a spacecraft and a descent probe. DAVINCI’s probe will be the first in the 21st century to brave Venus’ atmosphere as it descends from above the planet’s clouds down to its surface. Two other missions, NASA’s VERITAS and ESA’s (European Space Agency) Envision, will also explore Venus in the 2030s from the planet’s orbit.
The DAVINCI spacecraft will study Venus’ clouds and highlands during two flybys. It also will release a spherical probe, about 3 feet wide, that will plunge through the planet’s thick atmosphere and corrosive clouds, taking measurements and capturing high-resolution images of the Venusian surface as it descends below the clouds.
Here are some of DAVINCI’s coming “firsts” in Venus exploration:
Exploring Solar System’s One-of-a-Kind Terrain
The DAVINCI mission will be the first to closely explore Alpha Regio, a region known as a “tessera.” So far found only on Venus, where they make up about 8% of the surface, tesserae are highland regions similar in appearance to rugged mountains on Earth. Previous missions discovered these features using radar instruments, but of the many international spacecraft that dove through Venus’ atmosphere between 1966 and 1985, none studied or photographed tesserae.
Thought to be ancient continents, tesserae like Alpha Regio may be among the oldest surfaces on the planet, offering scientists access to rocks that are billions of years old.
By studying these rocks from above Alpha Regio, DAVINCI scientists may learn whether ancient Venus had continents and oceans, and how water may have influenced the surface.
Photographing One of the Oldest Surfaces on Venus
The DAVINCI probe will capture the first close-up views of Alpha Regio with its infrared and optical cameras; these will also be the first photos of the planet’s surface taken in more than 40 years.
With surface temperatures reaching 900° F and air pressure 90 times that of Earth’s, Venus’ harsh environment makes exploration challenging, while its opaque atmosphere obscures direct views. Typically, scientists rely on radar instruments from Earth or Venus-orbiting spacecraft to study its terrain.
But DAVINCI’s probe will descend through the atmosphere and below the clouds for a clear view of the mountains and plains. It will capture images comparable to an airplane’s landing view of Earth’s surface. Scientists will use the photos to compile 3D maps of Alpha Regio that will provide more detail than ever of Venus’ terrain, helping them look for rocks that are usually only made in association with water.
Unveiling Secrets of Venus’ Mysterious Lower Atmosphere
The DAVINCI mission will be the first to analyze the chemical composition of Venus’ lower atmosphere through measurements taken at regular intervals, starting from approximately 90,000 feet above the surface and continuing until just before impact.
This region is critical because it contains gases and chemical compounds that may originate from Venus’ lower clouds, surface, or even subsurface.
For example, sulfur compounds detected here could indicate whether Venusian volcanoes are currently active or were active in the recent past. Noble gases (like helium or xenon), on the other hand, remain chemically inert and maintain stable concentrations, offering invaluable clues about Venus’ ancient history, such as the planet’s past water inventory.
By comparing Venus’ noble gas composition with that of Earth and Mars, scientists can better understand why these planets — despite forming from similar starting materials — evolved into dramatically different worlds.
Moreover, DAVINCI’s measurements of isotopes and trace gases in the lower atmosphere will shed light on Venus’ water history, from ancient times to the present, and the processes that triggered the planet’s extreme greenhouse effect.
State-of-the-Art Technology to Study Venus in Detail
Thanks to modern technology, the DAVINCI probe will be able to do things 1980s-era spacecraft couldn’t.
The descent probe will be better equipped than previous probes to protect the sensitive electronics inside of it, as it will be lined on the inside with high-temperature, multi-layer insulation — layers of advanced ceramic and silica fabrics separated by aluminum sheets.
Venus’ super thick atmosphere will slow the probe’s descent, but a parachute will also be released to slow it down further. Most Earth-friendly parachute fabrics, like nylon, would dissolve in Venus’ sulfuric acid clouds, so DAVINCI will have to use a different type of material than previous Venus missions did: one that’s resistant to acids and five times stronger than steel.
Read More: Old Data Yields New Secrets as NASA’s DAVINCI Preps for Venus Trip
By Lauren Colvin, with Lonnie Shekhtman
NASA’s Goddard Space Flight Center, Greenbelt, Md.
NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is the principal investigator institution for DAVINCI and will perform project management for the mission, provide science instruments, as well as project systems engineering to develop the in-situ probe flight system that will enter the atmosphere of Venus. Goddard also leads the overall science for the mission with an external science team from across the United States. Lockheed Martin Space in Denver, Colorado, will build the carrier/relay spacecraft. DAVINCI is a mission within the Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington.
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By NASA
As any urban dweller who has lived through a heat wave knows, a shady tree can make all the difference. But what happens when there’s no shade available?
A recent study in Nature Communications used NASA satellite data to identify a major gap in global resilience to climate change: cities in the Global South have far less green space — and therefore less cooling capacity — than cities in the Global North. The terms Global North and Global South were used in the study to distinguish developed countries (mostly in the Northern Hemisphere) from developing nations (mostly in the Southern Hemisphere).
Cities tend to be hotter than nearby rural areas because of the urban heat island effect. Heat-trapping dark surfaces such as sidewalks, buildings, and roads absorb heat from the Sun’s rays, which raises the temperature of the city. Extreme heat poses serious health threats for urban residents, including dehydration, heat stroke, and even death. Though not a cure-all, greenery provides shade and releases moisture into the air, cooling the surroundings.
“Cities can strategically prioritize developing new green spaces in areas that have less green space,” said Christian Braneon, a climate scientist at NASA’s Goddard Institute for Space Studies in New York who was not affiliated with this study. “Satellite data can be really helpful for this.”
The Operational Land Imager (OLI) on the NASA and U.S. Geological Survey’s Landsat 8 satellite captured this natural color image of Sanaa, Yemen, on June 8, 2024. Sanaa, which has a hot, dry climate and little green space, had the second-lowest cooling capacity of 500 cities studied in a paper recently published in the journal Nature Communications. Wanmei Liang, NASA Earth Observatory An international team of researchers led by Yuxiang Li, a doctoral student at Nanjing University, analyzed the 500 largest cities in the world to compare their cooling capacities. They used data from the Landsat 8 satellite, jointly managed by NASA and the U.S. Geological Survey, to determine how effective green space was at cooling each city.
First, they calculated the average land surface temperature for the hottest month of 2018 for each city, as well as the average of the hottest months from 2017 to 2019. Next, the researchers used a metric called the Normalized Difference Vegetation Index (NDVI) to map how much green space each city had. The NDVI relies on the fact that healthy vegetation absorbs red light and reflects infrared light: the ratio of these wavelengths can show the density of healthy vegetation in a given satellite image.
Researchers found that cities in the Global South have just 70% of the greenery-related cooling capacity of cities in the Global North. The green spaces in an average Global South city cool the temperature by about 4.5 F (2.5 C). In an average Global North city, that cooling capacity is 6.5 F (3.6 C). This compounds an existing problem: cities in the South tend to be at lower latitudes (that is, nearer to the Equator), which are predicted to see more heat extremes in the coming years.
“It’s already clear that Global South countries will be impacted by heat waves, rising temperatures, and climatic extremes more than their Global North counterparts,” said Chi Xu, a professor of ecology at Nanjing University and a co-author of the study. The Global South has less capacity to adapt to heat because air conditioning is less common and power outages are more frequent.
Why do cities in the Global South struggle to stay cool? Cities in the Global South tend to have less green space than cities in the Global North. This mirrors studies of the disparities within cities, sometimes referred to as the “luxury effect”: wealthier neighborhoods tend to have more green space than poorer neighborhoods. “Wealthier cities also have more urban green spaces than the poorest cities,” Chi said.
It’s unlikely that urban planners can close the gap between the study’s worst-performing city (Mogadishu, Somalia) and the best-performing one (Charlotte, North Carolina).
Mogadishu is a dense city with a dry climate that limits vegetation growth. Still, there’s a lot that each city can learn from its neighbors. Within a given region, the researchers identified the city with the greatest cooling capacity and used that as a goal. They calculated the difference between the best-performing city in the region and every city nearby to get the potential additional cooling capacity. They found that cities’ average cooling capacity could be increased substantially — to as much as 18 F (10 C) — by systematically increasing green space quantity and quality.
“How you utilize green space is really going to vary depending on the climate and the urban environment you’re focused on,” said Braneon, whose research at NASA focuses on climate change and urban planning.
Greener cities in the U.S. and Canada have lower population densities. However, fewer people per square mile isn’t necessarily good for the environment: residents in low-density cities rely more on cars, and their houses tend to be bigger and less efficient. Braneon noted that there’s a suite of solutions beyond just planting trees or designating parks: Cities can increase cooling capacity by creating water bodies, seeding green roofs, and painting roofs or pavement lighter colors to reflect more light.
With a global study like this, urban planners can compare strategies for cities within the same region or with similar densities. “For newly urbanized areas that aren’t completely built out, there’s a lot of room to still change the design,” Braneon said.
By Madeleine Gregory
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Nov 26, 2024 Editor Rob Garner Contact Rob Garner rob.garner@nasa.gov Location Goddard Space Flight Center Related Terms
Climate Change Earth Goddard Institute for Space Studies Goddard Space Flight Center Landsat Landsat 8 / LDCM (Landsat Data Continuity Mission) View the full article
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By NASA
4 min read
Final Venus Flyby for NASA’s Parker Solar Probe Queues Closest Sun Pass
On Wednesday, Nov. 6, 2024, NASA’s Parker Solar Probe will complete its final Venus gravity assist maneuver, passing within 233 miles (376 km) of Venus’ surface. The flyby will adjust Parker’s trajectory into its final orbital configuration, bringing the spacecraft to within an unprecedented 3.86 million miles of the solar surface on Dec. 24, 2024. It will be the closest any human made object has been to the Sun.
Parker’s Venus flybys have become boons for new Venus science thanks to a chance discovery from its Wide-Field Imager for Parker Solar Probe, or WISPR. The instrument peers out from Parker and away from the Sun to see fine details in the solar wind. But on July 11, 2020, during Parker’s third Venus flyby, scientists turned WISPR toward Venus in hopes of tracking changes in the planet’s thick cloud cover. The images revealed a surprise: A portion of WISPR’s data, which captures visible and near infrared light, seemed to see all the way through the clouds to the Venusian surface below.
“The WISPR cameras can see through the clouds to the surface of Venus, which glows in the near-infrared because it’s so hot,” said Noam Izenberg, a space scientist at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.
Venus, sizzling at approximately 869 degrees Fahrenheit (about 465 C), was radiating through the clouds.
The WISPR images from the 2020 flyby, as well as the next flyby in 2021, revealed Venus’ surface in a new light. But they also raised puzzling questions, and scientists have devised the Nov. 6 flyby to help answer them.
Left: A series of WISPR images of the nightside of Venus from Parker Solar Probe’s fourth flyby showing near infrared emissions from the surface. In these images, lighter shades represent warmer temperatures and darker shades represent cooler. Right: A combined mosaic of radar images of Venus’ surface from NASA’s Magellan mission, where the brightness indicates radar properties from smooth (dark) to rough (light), and the colors indicate elevation from low (blue) to high (red). The Venus images correspond well with data from the Magellan spacecraft, showing dark and light patterns that line up with surface regions Magellan captured when it mapped Venus’ surface using radar from 1990 to 1994. Yet some parts of the WISPR images appear brighter than expected, hinting at extra information captured by WISPR’s data. Is WISPR picking up on chemical differences on the surface, where the ground is made of different material? Perhaps it’s seeing variations in age, where more recent lava flows added a fresh coat to the Venusian surface.
“Because it flies over a number of similar and different landforms than the previous Venus flybys, the Nov. 6 flyby will give us more context to evaluate whether WISPR can help us distinguish physical or even chemical properties of Venus’ surface,” Izenberg said.
After the Nov. 6 flyby, Parker will be on course to swoop within 3.8 million miles of the solar surface, the final objective of the historic mission first conceived over 65 years ago. No human-made object has ever passed this close to a star, so Parker’s data will be charting as-yet uncharted territory. In this hyper-close regime, Parker will cut through plumes of plasma still connected to the Sun. It is close enough to pass inside a solar eruption, like a surfer diving under a crashing ocean wave.
“This is a major engineering accomplishment,” said Adam Szabo, project scientist for Parker Solar Probe at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
The closest approach to the Sun, or perihelion, will occur on Dec. 24, 2024, during which mission control will be out of contact with the spacecraft. Parker will send a beacon tone on Dec. 27, 2024, to confirm its success and the spacecraft’s health. Parker will remain in this orbit for the remainder of its mission, completing two more perihelia at the same distance.
Parker Solar Probe is part of NASA’s Living with a Star program to explore aspects of the Sun-Earth system that directly affect life and society. The Living with a Star program is managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland, for NASA’s Science Mission Directorate in Washington. The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, manages the Parker Solar Probe mission for NASA and designed, built, and operates the spacecraft.
By Miles Hatfield
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Nov 04, 2024 Related Terms
Goddard Space Flight Center Heliophysics Heliophysics Division Parker Solar Probe (PSP) Solar Wind The Sun Venus Keep Exploring Discover More Topics From NASA
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On a mission to “touch the Sun,” NASA’s Parker Solar Probe became the first spacecraft to fly through the corona…
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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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