Dust cloud, aurora detected around Mars

Dust cloud, aurora detected 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. Credit: University of Colorado

A NASA spacecraft circling Mars has detected a mysterious dust cloud and a vibrant aurora, both unexpected phenomena on Earth's neighboring planet, researchers said Wednesday.

NASA's Mars Atmosphere and Volatile Evolution (MAVEN) detected the aurora—known on Earth as the Northern lights—in December, so they were nicknamed "Christmas Lights," according to a statement issued by NASA on the same day as the findings were presented at a Texas astronomy conference.

"For five days just before December 25, MAVEN saw a bright ultraviolet auroral glow spanning Mars' northern hemisphere," it said.

Aurora are seen when geomagnetic storms unleashed by eruptions on the Sun cause energetic particles like electrons to crash into the atmosphere, 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, Imaging Ultraviolet Spectograph team member at the University of Colorado.

"The electrons producing it must be really energetic."

Experts believe the source of the energetic particles for the Mars aurora is the Sun, because MAVEN's Solar Energetic Particle instrument "detected a huge surge in at the onset of the aurora," NASA said.

Since Mars lost its protective magnetic field billions of years ago, the solar particles can directly strike the atmosphere and penetrate deeply.

Dust cloud, aurora detected around Mars
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. Credit: University of Colorado

Scientists also observed an unusual , with the help of MAVEN, about 93 miles (150 kilometers) above the Red Planet's surface.

The source of the dust, its contents, and whether it is temporary or permanent, are all unknown.

"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," NASA said.

"However, no known process on Mars can explain the appearance of dust in the observed locations from any of these sources."

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

MAVEN launched toward Mars in November 2013, on a mission to study how the planet lost most of its water and atmosphere.

The unmanned orbiter is four months into its one-year mission.

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© 2015 AFP

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Mar 18, 2015
The aurora would likely have been from a CME, and the dust cloud could be a result of a magnetic vortex reaching the ground and grabbing up particles.

Mar 18, 2015
Experts believe the source of the energetic particles...

Funny someone can be called and "expert" when they are oblivious to the actual processes. One of these days these dolts will start experimenting with electric discharge to find the real cause, in about 50 years or so...

Mar 19, 2015
A dyslexic eye twister: 'cloud could'

Mar 22, 2015
That which is "unexpected" to some, is predictable phenomena to others...


Mar 22, 2015
By "predictable" most reasonable people would assume you are claiming someone used EU theory to predict the solar panel washing events BEFORE they happened. So please post a link to this prediction, as it wasn't in the video you already posted.

Mar 23, 2015
@cd: Your silence = no prediction.

The video dismisses the ability of Mars wind to pick up large amounts of dust by comparing its density and temperature to those of Earth. By looking at Stokes' Law and the dynamic viscosities of ideal gases, we can investigate all the parameters that EU decided to ignore to come to that fallacious conclusion. First the settling velocity at http://en.wikiped..._a_Fluid can be used, assuming that an object can be lifted into the air if an upward-moving wind is faster than the object's terminal velocity. The lower the terminal velocity, the less wind is needed to pick up the object. The equation is directly proportional to the difference between the object's density and the fluid's density, but in this case the air density, whether on Mars or on Earth, is so much smaller than that of a common mineral that it can essentially be ignored.

Mar 23, 2015
The terminal velocity is directly proportional to g, the acceleration due to gravity. Here Mars has a distinct advantage, as Martian gravity is only 38% as strong as Earth's. We also see the terminal velocity is inversely proportional to the dynamic viscosity http://en.wikiped...of_a_gas , which puts a pure CO2 atmosphere at Martian temperatures at 61% the viscosity of an air atmosphere at typical Earth temperatures (probably an underestimate because Mars has some nitrogen). This works against Mars but is a smaller affect than that of gravity.

Mar 23, 2015
At the end of the equation we see that the terminal velocity is proportional to the radius squared. This means that even the slightest breeze can carry very small objects, and here we see another Mars advantage. It is dry and has been for a very long time. It has had billions of years to grind its surface into very fine dust, and the very low water levels in the atmosphere means these dust grains won't accumulate water or ice and get bigger as they float around. Earth on the other hand, with its abundant water, washes dust out of the air very quickly. Dry air will lead to static charges lingering longer, causing dust particles to repel each other or the ground, leading to them being suspended longer. And what about Martian wind? Storms with sustained winds of 61 km/hr and gusts up to 94 km/hr. The Martian atmosphere is capable of picking dust grains about as well as Earth's, but once aloft they will linger far longer - perfect conditions for global dust storms.

Mar 25, 2015
By "predictable" most reasonable people would assume you are claiming someone used EU theory to predict the solar panel washing events BEFORE they happened. So please post a link to this prediction, as it wasn't in the video you already posted.

Most reasonable people would think you are ridiculous. watch the video again without bias and try to see the larger picture instead of fixating on static charge on a solar cell. The rest of your babble also seems pointless so wrap your head around the idea of hundreds of dust devils occurring at the same time, that has nothing to do with how dry the dust is. Our instruments have already proven dust devils on Mars and in the Arizona desert are dynamically electrical in nature, we just do not see those hundreds happen at the same time on earth, though I have seen a half dozen or so within a relative proximity.

Mar 25, 2015

An electrics charge doesn't create dust devils. Meteorological conditions create dust devils, the whirling dust particles then become charged, it's basic science, something you EU nutters can't grasp.

Mar 26, 2015
It's not the 19th century, fluid dynamics does a poor job describing a weakly ionized plasma in the earth's vertical electric field.
When science advances not everyone gets the memo.

Apr 04, 2015
Most reasonable people would think you are ridiculous. watch the video again without bias
TYPICAL eu pseudoscience

you are actually advocating the ignoring of the SCIENCE and acceptance of a VIDEO of someone's conjecture
re-read that comment from barakn
the BEST paraphrase is here
@cd: Your silence = no prediction
just because someone SAYS there is a prediction or that they believe something is predicted is NOT EMPIRICAL EVIDENCE of said prediction

your delusions are YOURS ALONE, and are only shared with those of your own faith
not of the scientific community
unless you can provide the EVIDENCE, then you are simply parroting a dogma or a set of tenets
that is RELIGION

just because YOU FELL FOR THE CON doesn't mean we all did
in this case, it is your belief that modern astro's don't know about plasma physics
that's been proven a LIE over and over

and even PLASMA PHYSICISTS use MHD you idiot

Apr 06, 2015
Ironic you would bring MHD to the table as Alfven who wrote the book on it was considered a loon by main stream science for forty years. Ten years after his Nobel prize he said the astrophysical community still had their heads up their bums. Not to shabby a career for an electrical engineer. As for idiots, tell us again how electrical engineers have no business in astrophysics.

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