by iamlucky13 » Tue Sep 04, 2007 6:53 pm
FieryIce wrote:How can an enviroment with little atmosphere contain or hold a storm or have a storm front? How can an eviroment with little atmosphere have a planet wide dust storm? In the images of the planet wide storm where is the storm front, how is it created? Where is the dust on the rovers?
The fact that it's planetwide is rather interesting. On earth the oceans are the dominant influence on the weather, and storms are localized based on the ocean or continent they form in. On Mars you don't have the same huge discontinuties interferring with large storms forming. I couldn't tell you where the front is or specifically how its created.
Although the Martian atmosphere is very thin, it is still capable of experiencing pressure differences similar to those we see on earth, and thus the rapid winds that are able to carry dust into the air. It's really the planetwide scale and monthlong duration that allows these storms to be as dramatic as they are, and the low gravity helps, too. I don't think they get as crazy as a sandstorm in the Sahara, but because they extend much higher into the atmosphere, even a thin haze of dust can cut the light quite a bit.
Because the rovers are exposed and generally pretty smooth-surfaced, they tend not to accumulate to much dust. Very fortunately, a lot of it blows off as fast as it can deposity. The team has been taking a lot of pictures of the rover deck lately to get an idea how much dust actually is there. Also, they mentioned in the latest update seeing a jump in Opportunity's power output that looks like another dust-clearing wind event.
http://marsrovers.jpl.nasa.gov/newsroom ... 0824a.html[quote="FieryIce"]How can an enviroment with little atmosphere contain or hold a storm or have a storm front? How can an eviroment with little atmosphere have a planet wide dust storm? In the images of the planet wide storm where is the storm front, how is it created? Where is the dust on the rovers?[/quote]
The fact that it's planetwide is rather interesting. On earth the oceans are the dominant influence on the weather, and storms are localized based on the ocean or continent they form in. On Mars you don't have the same huge discontinuties interferring with large storms forming. I couldn't tell you where the front is or specifically how its created.
Although the Martian atmosphere is very thin, it is still capable of experiencing pressure differences similar to those we see on earth, and thus the rapid winds that are able to carry dust into the air. It's really the planetwide scale and monthlong duration that allows these storms to be as dramatic as they are, and the low gravity helps, too. I don't think they get as crazy as a sandstorm in the Sahara, but because they extend much higher into the atmosphere, even a thin haze of dust can cut the light quite a bit.
Because the rovers are exposed and generally pretty smooth-surfaced, they tend not to accumulate to much dust. Very fortunately, a lot of it blows off as fast as it can deposity. The team has been taking a lot of pictures of the rover deck lately to get an idea how much dust actually is there. Also, they mentioned in the latest update seeing a jump in Opportunity's power output that looks like another dust-clearing wind event.
http://marsrovers.jpl.nasa.gov/newsroom/pressreleases/20070824a.html