Organizations – Universities
Jet Propulsion Laboratory, Pasadena, Calif.
NASA Headquarters, Washington
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.
Jet Propulsion Laboratory, Pasadena, Calif.
NASA Headquarters, Washington DC
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.
NASA’s Webb Observatory Requires More Time for Testing and Evaluation; New Launch Window Under Review
NASA Release by Jen Rae Wang / Steve Cole
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.
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
“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 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.”