Showing posts with label NASA's Mars Atmosphere and Volatile Evolution (MAVEN). Show all posts
Showing posts with label NASA's Mars Atmosphere and Volatile Evolution (MAVEN). Show all posts

Thursday, March 19, 2015

NASA Spacecraft Detects Aurora and Mysterious Dust Cloud around Mars

Artist’s conception of MAVEN’s Imaging UltraViolet Spectrograph (IUVS) observing the “Christmas Lights Aurora" on Mars. MAVEN observations show that aurora on Mars is similar to Earth’s "Northern Lights" but has a different origin.Image Credit: University of Colorado
 
A map of IUVS’s auroral detections in December 2014 overlaid on Mars’ surface. The map shows that the aurora was widespread in the northern hemisphere, not tied to any geographic location. The aurora was detected in all observations during a 5-day period. Image Credit: University of Colorado. Hi-Res image
 

NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has observed two unexpected phenomena in the Martian atmosphere: an unexplained high-altitude dust cloud and aurora that reaches deep into the Martian atmosphere.

The presence of the dust at orbital altitudes from about 93 miles (150 kilometers) to 190 miles (300 kilometers) above the surface was not predicted. Although the source and composition of the dust are unknown, there is no hazard to MAVEN and other spacecraft orbiting Mars.

"If the dust originates from the atmosphere, this suggests we are missing some fundamental process in the Martian atmosphere," said Laila Andersson of the University of Colorado's Laboratory for Atmospherics and Space Physics (CU LASP), Boulder, Colorado.

The cloud was detected by the spacecraft’s Langmuir Probe and Waves (LPW) instrument, and has been present the whole time MAVEN has been in operation. It is unknown if the cloud is a temporary
phenomenon or something long lasting. The cloud density is greatest at lower altitudes. However, even in the densest areas it is still very thin. So far, no indication of its presence has been seen in observations from any of the other MAVEN instruments.

Possible sources for the observed dust include dust wafted up from the atmosphere; dust coming from Phobos and Deimos, the two moons of Mars; dust moving in the solar wind away from the sun; or debris orbiting the sun from comets. However, no known process on Mars can explain the appearance of dust in the observed locations from any of these sources.

MAVEN's Imaging Ultraviolet Spectrograph (IUVS) observed what scientists have named "Christmas lights." For five days just before Dec. 25, MAVEN saw a bright ultraviolet auroral glow spanning Mars' northern hemisphere. Aurora, known on Earth as northern or southern lights, are caused by energetic particles like electrons crashing down into the atmosphere and causing the gas to glow.

"What's especially surprising about the aurora we saw is how deep in the atmosphere it occurs - much deeper than at Earth or elsewhere on Mars,” said Arnaud Stiepen, IUVS team member at the University of Colorado. “The electrons producing it must be really energetic."

The source of the energetic particles appears to be the sun. MAVEN's Solar Energetic Particle instrument detected a huge surge in energetic electrons at the onset of the aurora. Billions of years ago, Mars lost a global protective magnetic field like Earth has, so solar particles can directly strike the atmosphere. The electrons producing the aurora have about 100 times more energy than you get from a spark of house current, so they can penetrate deeply in the atmosphere.

The findings are being presented at the 46th Lunar and Planetary Science Conference in The Woodlands, Texas.

MAVEN was launched to Mars on Nov. 18, 2013, to help solve the mystery of how the Red Planet lost most of its atmosphere and much of its water. The spacecraft arrived at Mars on Sept. 21, and is four months into its one-Earth-year primary mission.

"The MAVEN science instruments all are performing nominally, and the data coming out of the mission are excellent," said Bruce Jakosky of CU LASP, Principal Investigator for the mission.

MAVEN is part of the agency's Mars Exploration Program, which includes the Opportunity and Curiosity rovers, the Mars Odyssey and Mars Reconnaissance Orbiter spacecraft currently orbiting the planet.

NASA's Mars Exploration Program seeks to characterize and understand Mars as a dynamic system, including its present and past environment, climate cycles, geology and biological potential. In parallel, NASA is developing the human spaceflight capabilities needed for its journey to Mars or a future round-trip mission to the Red Planet in the 2030’s.

MAVEN's principal investigator is based at the University of Colorado's Laboratory for Atmospheric and Space Physics, and NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN project. Partner institutions include Lockheed Martin, the University of California at Berkeley, and NASA's Jet Propulsion Laboratory.

For images related to the findings, visit:  http://www.nasa.gov/maven

 
Contact
 
Dwayne Brown
Headquarters, Washington 

email:  dwayne.c.brown@nasa.gov
202-358-1726

Nancy Neal-Jones / Bill Steigerwald
Goddard Space Flight Center, Greenbelt, Md. 

email:  nancy.n.jones@nasa.gov / william.a.steigerwald@nasa.gov
301-286-0039 / 301-286-5017

Jim Scott
University of Colorado, Boulder, Colorado

email: jim.scott@colorado.edu
303-492-3114
 
Source:  NASA's News
 

Wednesday, October 15, 2014

NASA Mission Provides Its First Look at Martian Upper Atmosphere

Three views of an escaping atmosphere, obtained by MAVEN’s Imaging Ultraviolet Spectrograph. By observing all of the products of water and carbon dioxide breakdown, MAVEN's remote sensing team can characterize the processes that drive atmospheric loss on Mars.Image Credit: University of Colorado/NASA. Hi Res Image
NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has provided scientists their first look at a storm of energetic solar particles at Mars, produced unprecedented ultraviolet images of the tenuous oxygen, hydrogen, and carbon coronas surrounding the Red Planet, and yielded a comprehensive map of highly-variable ozone in the atmosphere underlying the coronas.

The spacecraft, which entered Mars' orbit Sept. 21, now is lowering its orbit and testing its instruments. MAVEN was launched to Mars in November 2013, to help solve the mystery of how the Red Planet lost most of its atmosphere.

"All the instruments are showing data quality that is better than anticipated at this early stage of the mission," said Bruce Jakosky, MAVEN Principal Investigator at the University of Colorado, Boulder. "All instruments have now been turned on -- although not yet fully checked out -- and are functioning nominally. It's turning out to be an easy and straightforward spacecraft to fly, at least so far. It really looks as if we're headed for an exciting science mission."

Solar energetic particles (SEPs) are streams of high-speed particles blasted from the sun during explosive solar activity like flares or coronal mass ejections (CMEs). Around Earth, SEP storms can damage the sensitive electronics on satellites. At Mars, they are thought to be one possible mechanism for driving atmospheric loss.

A solar flare on Sept. 26 produced a CME that was observed by NASA satellites on both sides of the sun. Computer models of the CME propagation predicted the disturbance and the accompanying SEPs would reach Mars on Sept. 29. MAVEN's Solar Energetic Particle instrument was able to observe the onset of the event that day.

"After traveling through interplanetary space, these energetic particles of mostly protons deposit their energy in the upper atmosphere of Mars," said SEP instrument lead Davin Larson of the Space Sciences Laboratory at the University of California, Berkeley. "A SEP event like this typically occurs every couple weeks. Once all the instruments are turned on, we expect to also be able to track the response of the upper atmosphere to them."

The hydrogen and oxygen coronas of Mars are the tenuous outer fringe of the planet's upper atmosphere, where the edge of the atmosphere meets space. In this region, atoms that were once a part of carbon dioxide or water molecules near the surface can escape to space. These molecules control the climate, so following them allows us to understand the history of Mars over the last four billion years and to track the change from a warm and wet climate to the cold, dry climate we see today. MAVEN observed the edges of the Martian atmosphere using the Imaging Ultraviolet Spectrograph (IUVS), which is sensitive to the sunlight reflected by these atoms.

"With these observations, MAVEN's IUVS has obtained the most complete picture of the extended Martian upper atmosphere ever made," said MAVEN Remote Sensing Team member Mike Chaffin of the University of Colorado, Boulder. "By measuring the extended upper atmosphere of the planet, MAVEN directly probes how these atoms escape to space. The observations support our current understanding that the upper atmosphere of Mars, when compared to Venus and Earth, is only tenuously bound by the Red Planet's weak gravity."

IUVS also created a map of the atmospheric ozone on Mars by detecting the absorption of ultraviolet sunlight by the molecule.

"With these maps we have the kind of complete and simultaneous coverage of Mars that is usually only possible for Earth," said MAVEN Remote Sensing Team member Justin Deighan of the University of Colorado, Boulder. "On Earth, ozone destruction by refrigerator CFCs is the cause of the polar ozone hole. On Mars, ozone is just as easily destroyed by the byproducts of water vapor breakdown by ultraviolet sunlight. Tracking the ozone lets us track the photochemical processes taking place in the Martian atmosphere. We'll be exploring this in more complete detail during MAVEN's primary science mission."

There will be about two weeks of additional instrument calibration and testing before MAVEN starts its primary science mission. This includes an end-to-end test to transmit data between NASA's Curiosity rover on the surface of Mars and Earth using the MAVEN mission's Electra telecommunications relay. The mission aims to start full science gathering in early to mid-November.

MAVEN's principal investigator is based at the University of Colorado's Laboratory for Atmospheric and Space Physics. The university provided two science instruments and leads science operations, as well as education and public outreach, for the mission. The University of California at Berkeley's Space Sciences Laboratory also provided four science instruments for the mission. NASA's Goddard Space Flight Center in Greenbelt, Maryland manages the MAVEN project and provided two science instruments for the mission.  Lockheed Martin built the spacecraft and is responsible for mission operations. NASA's Jet Propulsion Laboratory in Pasadena, California provides navigation and Deep Space Network support, as well as the Electra telecommunications relay hardware and operations.

For more about MAVEN, visit:  http://www.nasa.gov/maven


Dwayne Brown
Headquarters, Washington
202-358-1726
dwayne.c.brown@nasa.gov

Nancy Jones / Bill Steigerwald
Goddard Space Flight Center, Greenbelt, Md.
301-286-0039 / 301-286-5017
nancy.n.jones@nasa.gov / william.a.steigerwald@nasa.gov