Hola amigos: A VUELO DE UN QUINDE EL BLOG., hemos recibido de la Agencia Espacial NASA, la información del descubrimiento de la NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft, de ha
observado dos fenómenos inesperados en la atmósfera de Marte: una nube de polvo sin explicación a gran altitud y aurora que llega profundamente en la atmósfera marciana.
La presencia de polvo en altitudes orbitales de aproximadamente 93 millas (150 kilómetros) a 190 millas (300 kilómetros) por encima de la superficie no se predijo. Aunque se desconoce el origen y la composición del polvo, no hay peligro para MAVEN y otras naves espaciales en órbita alrededor de Marte.
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
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.
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
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:
NASA
Guillermo Gonzalo Sánchez Achutegui
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