Organizations – Universities

NASA’s InSight ‘Hears’ Peculiar Sounds on Mars

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Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
andrew.c.good@jpl.nasa.gov

Alana Johnson
NASA Headquarters, Washington
alana.r.johnson@nasa.gov

 

 

Clouds drift over the dome-covered seismometer
NASA’s InSight used its Instrument Context Camera (ICC) beneath the lander’s deck to image these drifting clouds at sunset. This series of images was taken on April 25, 2019, the 145th Martian day, or sol, of the mission, starting at around 6:30 p.m. Mars local time. Credit: NASA/JPL-Caltech

 

Put an ear to the ground on Mars and you’ll be rewarded with a symphony of sounds. Granted, you’ll need superhuman hearing, but NASA’s InSight lander comes equipped with a very special “ear.”

The spacecraft’s exquisitely sensitive seismometer, called the Seismic Experiment for Interior Structure (SEIS), can pick up vibrations as subtle as a breeze. The instrument was provided by the French space agency, Centre National d’Études Spatiales (CNES), and its partners.

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Scientists Finally Know What Time It Is on Saturn

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Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif. 

JoAnna Wendel 
NASA Headquarters, Washington DC

 

A view from NASA’s Cassini spacecraft shows Saturn’s northern hemisphere in 2016 as that part of the planet nears its northern hemisphere summer solstice. A year on Saturn is 29 Earth years; days only last 10:33:38, according to a new analysis of Cassini data. Credit: NASA/JPL-Caltech/Space Science Institute

 

Using new data from NASA’s Cassini spacecraft, researchers believe they have solved a longstanding mystery of solar system science: the length of a day on Saturn. It’s 10 hours, 33 minutes and 38 seconds. 

The figure has eluded planetary scientists for decades, because the gas giant has no solid surface with landmarks to track as it rotates, and it has an unusual magnetic field that hides the planet’s rotation rate.

The answer, it turned out, was hidden in the rings. 

 

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NASA’s Webb Observatory Requires More Time for Testing and Evaluation; New Launch Window Under Review

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NASA Release by Jen Rae Wang / Steve Cole
Headquarters, Washington’

James_Webb_Space_Telescope.jpg 

 

NASA’s James Webb Space Telescope currently is undergoing final integration and test phases that will require more time to ensure a successful mission. After an independent assessment of remaining tasks for the highly complex space observatory, Webb’s previously revised 2019 launch window now is targeted for approximately May 2020. 

“Webb is the highest priority project for the agency’s Science Mission Directorate, and the largest international space science project in U.S. history. All the observatory’s flight hardware is now complete, however, the issues brought to light with the spacecraft element are prompting us to take the necessary steps to refocus our efforts on the completion of this ambitious and complex observatory,” said acting NASA Administrator Robert Lightfoot.

 

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Solar Storms Can Drain Electrical Charge Above Earth

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Written by Carol Rasmussen
NASA’s Earth Science News Team

A solar eruption on Sept. 26, 2014, seen by NASA’s Solar Dynamics Observatory. If erupted solar material reaches Earth, it can deplete the electrons in the upper atmosphere in some locations while adding electrons in others, disrupting communications either way. Credit: NASA

 

New research on solar storms finds that they not only can cause regions of excessive electrical charge in the upper atmosphere above Earth’s poles, they also can do the exact opposite: cause regions that are nearly depleted of electrically charged particles. The finding adds to our knowledge of how solar storms affect Earth and could possibly lead to improved radio communication and navigation systems for the Arctic. 

A team of researchers from Denmark, the United States and Canada made the discovery while studying a solar storm that reached Earth on Feb. 19, 2014. The storm was observed to affect the ionosphere in all of Earth’s northern latitudes. Its effects on Greenland were documented by a network of global navigation satellite system, or GNSS, stations as well as geomagnetic observatories and other resources. Attila Komjathy of NASA’s Jet Propulsion Laboratory, Pasadena, California, developed software to process the GNSS data and helped with the data processing. The results were published in the journal Radio Science.

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NASA Satellite Finds Unreported Source of Toxic Air Pollution

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Human-made sulfur dioxide emissions from a medium-size power plant
New research has detected smaller sulfur dioxide concentrations and sources around the world, including human-made sources such as medium-size power plants and oil-related activities.
Credit: EPA
 
Data from NASA’s Aura spacecraft, illustrated here, were analyzed by scientists to produce improved estimates of sulfur dioxide sources and concentrations worldwide between 2005 and 2014.

Credit: NASA

Using a new satellite-based method, scientists at NASA, Environment and Climate Change Canada, and two universities have located 39 unreported and major human-made sources of toxic sulfur dioxide emissions.

A known health hazard and contributor to acid rain, sulfur dioxide (SO2) is one of six air pollutants regulated by the U.S. Environmental Protection Agency. Current, sulfur dioxide monitoring activities include the use of emission inventories that are derived from ground-based measurements and factors, such as fuel usage. The inventories are used to evaluate regulatory policies for air quality improvements and to anticipate future emission scenarios that may occur with economic and population growth.

But, to develop comprehensive and accurate inventories, industries, government agencies and scientists first must know the location of pollution sources.

“We now have an independent measurement of these emission sources that does not rely on what was known or thought known,” said Chris McLinden, an atmospheric scientist with Environment and Climate Change Canada in Toronto and lead author of the study published this week in Nature Geosciences. 

“When you look at a satellite picture of sulfur dioxide, you end up with it appearing as hotspots – bull’s-eyes, in effect — which makes the estimates of emissions easier.”

The 39 unreported emission sources, found in the analysis of satellite data from 2005 to 2014, are clusters of coal-burning power plants, smelters, oil and gas operations found notably in the Middle East, but also in Mexico and parts of Russia. In addition, reported emissions from known sources in these regions were — in some cases — two to three times lower than satellite-based estimates. 

Altogether, the unreported and underreported sources account for about 12 percent of all human-made emissions of sulfur dioxide – a discrepancy that can have a large impact on regional air quality, said McLinden.

The research team also located 75 natural sources of sulfur dioxide — non-erupting volcanoes slowly leaking the toxic gas throughout the year. While not necessarily unknown, many volcanoes are in remote locations and not monitored, so this satellite-based data set is the first to provide regular annual information on these passive volcanic emissions.

“Quantifying the sulfur dioxide bull’s-eyes is a two-step process that would not have been possible without two innovations in working with the satellite data,” said co-author Nickolay Krotkov, an atmospheric scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. 

First was an improvement in the computer processing that transforms raw satellite observations from the Dutch-Finnish Ozone Monitoring Instrument aboard NASA’s Aura spacecraft into precise estimates of sulfur dioxide concentrations. Krotkov and his team now are able to more accurately detect smaller sulfur dioxide concentrations, including those emitted by human-made sources such as oil-related activities and medium-size power plants. 

Being able to detect smaller concentrations led to the second innovation. McLinden and his colleagues used a new computer program to more precisely detect sulfur dioxide that had been dispersed and diluted by winds. They then used accurate estimates of wind strength and direction derived from a satellite data-driven model to trace the pollutant back to the location of the source, and also to estimate how much sulfur dioxide was emitted from the smoke stack.

“The unique advantage of satellite data is spatial coverage,” said Bryan Duncan, an atmospheric scientist at Goddard. 

“This paper is the perfect demonstration of how new and improved satellite datasets, coupled with new and improved data analysis techniques, allow us to identify even smaller pollutant sources and to quantify these emissions over the globe.”

The University of Maryland, College Park, and Dalhousie University in Halifax, Nova Scotia, contributed to this study.

For more information about, and access to, NASA’s air quality data, visit: http://so2.gsfc.nasa.gov/

NASA uses the vantage point of space to increase our understanding of our home planet, improve lives, and safeguard our future. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing. 

For more information about NASA Earth science research, visit: http://www.nasa.gov/earth

Less Algae, Not Clearer Water, Keeps Tahoe Blue

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Lake Tahoe is renowned for its intense blue hue. (Image credit: Wikimedia Commons)

Lake Tahoe’s iconic blueness is more strongly related to the lake’s algal concentration than to its clarity, according to research in “Tahoe: State of the Lake Report 2015,” released today by the Tahoe Environmental Research Center (TERC) of the University of California, Davis. The lower the algal concentration, the bluer the lake.

Data from a research buoy in the lake, owned and operated by NASA’s Jet Propulsion Laboratory, Pasadena, California, enabled Shohei Watanabe, a postdoctoral researcher at TERC, to create a Blueness Index that quantified Lake Tahoe’s color for the first time.

The assumption that lake clarity is tied to blueness has driven advocacy and management efforts in the Lake Tahoe Basin for decades. But Watanabe’s research showed that at times of the year when the lake’s clarity increases, its blueness decreases, and vice versa.

Watanabe combined the blueness measurements with data on clarity. Clarity is measured by observing the depth at which a dinner-plate-sized white disk remains visible when lowered into the water. He was surprised to find that blueness and clarity did not correspond. In fact, they varied in opposite directions.

This is due to seasonal interplay among sediment, algae and nutrients in the lake. Clarity is controlled by sediment. Blueness is controlled by algal concentration, which in turn is controlled by the level of nutrients available to the algae.

The JPL buoy used in the study is one of four buoys established by NASA with support from TERC to calibrate and validate measurements taken by satellites flying overhead. “This particular buoy has instruments beneath the water looking up and an instrument on the buoy looking down,” said JPL’s Simon Hook, who collaborated with Watanabe during his research. “The combination of instruments in and above the water was used in this study to look at how light is being scattered and attenuated.

That tells you something about both the color and the clarity of the lake.”

The finding is good news, according to Geoffrey Schladow, director of TERC and a civil engineering professor at UC Davis. “It shows that we better understand how Lake Tahoe works, and it reinforces the importance of controlling nutrient inputs to the lake, whether from the forest, the surrounding lawns or even from the air. It’s particularly encouraging that blueness has been increasing over the last three years.”

Past State of the Lake Reports
The University of California, Davis, has conducted continuous monitoring of Lake Tahoe since 1968, amassing a unique record of change for one of the world’s most beautiful and vulnerable lakes.

In the UC Davis Tahoe: State of the Lake Report, we summarize how natural variability, long term change and human activity have affected the lake’s clarity, physics, chemistry and biology over that period.

UC Davis provides acess to past reports, starting at 2007 to the current report. You can access them on the UC Davis Past website at: Past State of Lake Tahoe’s Reports.

More Information From the Reseacher and NASA
For more information on Watanabe’s research and other highlights of the State of the Lake report, visit: http://news.ucdavis.edu/search/news_detail.lasso?id=11265

NASA uses the vantage point of space to increase our understanding of our home planet, improve lives and safeguard our future. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing.

For more information about NASA’s Earth science activities, visit: http://www.nasa.gov/earth

NASA Spacecraft Achieves Unprecedented Success Studying Mercury

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NASA’s MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft traveled more than six and a half years before it was inserted into orbit around Mercury on March 18, 2011. (Image Credit: NASA/JHU APL/Carnegie Institution of Washington)
 


After extraordinary science findings and technological innovations, a NASA spacecraft launched in 2004 to study Mercury will impact the planet’s surface, most likely on April 30, after it runs out of propellant.

NASA’s MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft will impact the planet at more than 8,750 miles per hour (3.91 kilometers per second) on the side of the planet facing away from Earth. Due to the expected location, engineers will be unable to view in real time the exact location of impact.

On Tuesday, mission operators in mission control at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, completed the fourth in a series of orbit correction maneuvers designed to delay the spacecraft’s impact into the surface of Mercury. The last maneuver is scheduled for Friday, April 24.

“Following this last maneuver, we will finally declare the spacecraft out of propellant, as this maneuver will deplete nearly all of our remaining helium gas,” said Daniel O’Shaughnessy, mission systems engineer at APL. “At that point, the spacecraft will no longer be capable of fighting the downward push of the sun’s gravity.”

Although Mercury is one of Earth’s nearest planetary neighbors, little was known about the planet prior to the MESSENGER mission.

“For the first time in history we now have real knowledge about the planet Mercury that shows it to be a fascinating world as part of our diverse solar system,” said John Grunsfeld, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “While spacecraft operations will end, we are celebrating MESSENGER as more than a successful mission. It’s the beginning of a longer journey to analyze the data that reveals all the scientific mysteries of Mercury.” 

The spacecraft traveled more than six and a half years before it was inserted into orbit around Mercury on March 18, 2011. The prime mission was to orbit the planet and collect data for one Earth year. The spacecraft’s healthy instruments, remaining fuel, and new questions raised by early findings resulted in two approved operations extensions, allowing the mission to continue for almost four years and resulting in more scientific firsts.

One key science finding in 2012 provided compelling support for the hypothesis that Mercury harbors abundant frozen water and other volatile materials in its permanently shadowed polar craters.

Data indicated the ice in Mercury’s polar regions, if spread over an area the size of Washington, would be more than two miles thick. For the first time, scientists began seeing clearly a chapter in the story of how the inner planets, including Earth, acquired water and some of the chemical building blocks for life.

A dark layer covering most of the water ice deposits supports the theory that organic compounds,  as well as water, were delivered from the outer solar system to the inner planets and may have led to prebiotic chemical synthesis and, thusly, life on Earth.

“The water now stored in ice deposits in the permanently shadowed floors of impact craters at Mercury’s poles most likely was delivered to the innermost planet by the impacts of comets and volatile-rich asteroids,” said Sean Solomon, the mission’s principal investigator, and director of Columbia University’s Lamont-Doherty Earth Observatory in Palisades, New York. “Those same impacts also likely delivered the dark organic material.”

In addition to science discoveries, the mission provided many technological firsts, including the development of a vital heat-resistant and highly reflective ceramic cloth sunshade that isolated the spacecraft’s instruments and electronics from direct solar radiation – vital to mission success given Mercury’s proximity to the sun. The technology will help inform future designs for planetary missions within our solar system.

“The front side of the sunshade routinely experienced temperatures in excess of 300° Celsius (570° Fahrenheit), whereas the majority of components in its shadow routinely operated near room temperature (20°C or 68°F),” said Helene Winters, mission project manager at APL. “This technology to protect the spacecraft’s instruments was a key to mission success during its prime and extended operations.”

The spacecraft was designed and built by APL. The lab manages and operates the mission for NASA’s Science Mission Directorate. The mission is part of NASA’s Discovery Program, managed for the directorate by the agency’s Marshall Space Flight Center in Huntsville, Alabama.

For a complete listing of science findings and technological achievements of the mission visit:

http://www.nasa.gov/messenger