aesmael

Originally published at a denizen's entertainment. You can comment here or there.

( Large in extent image behind cut )

A new month, so time for a new desktop background. I had been using art shared from other people, but this time chose a screenshot I'd taken in Celestia a few days before.

The perspective is from the surface of Deimos, looking down to Mars below. Much closer than our moon to Earth. If you look along the terminator marking day from night, a white spot is visible. That is Phobos, the other moon, caught in its (less than) 8 hour orbit at a dramatic moment.

Apart from its large crater Stickney (not shown), Phobos is famous for its low and fast orbit, which contrary to that of our moon is decaying lower and faster. When it drops not much lower, tidal forces from Mars will tear it apart and for awhile Mars may be ringed until those fragments rain down upon its surface.

Deimos gets much less love, but perhaps when it is the last moon remaining this will change.

    From this post I learn there is a small chance of a recently discovered asteroid colliding with Mars. Naturally I went to my own favoured sources to get more information.
    Anyway, there is news here. Numbers are all there. The object is about the same size as the one that exploded over Tunguska in 1908 but since Mars has a thinner atmosphere than Earth, if it hits it is expected to make a crater roughly 1 km in diameter.
    There have not been many observed impacts, however, so if this object (2007 WDS) does hit
 it will be a good opportunity to test the models that have been developed in the past. Previous impact possibilities (aimed at Earth usually because that is where we are and where we look to guard) have on further observation negligible chance of impact (with one possible exception). It is likely that further observations and refined orbital predictions will also lead to the conclusion 2007 WDS is going to miss Mars but from what I have been reading most scientists are hoping it will hit.
    It seems odd to me at first thought, to be hoping for catastrophic change to a planet's surface, but then I am quite preservationist in instinct. There is no conscious agency behind the asteroid's movement, which would be one of a few more momentous discoveries than an impact and a large part of my initial concern over such an event comes from my perspective in time, I think.
    Humans are ephemeral creatures, our culture barely less so. There have likely been several such impacts on Mars - indeed, on Earth too - since the beginning of recorded history, but not since we have been able to detect them in advance. Over longer timescales this is insignificant, a commonplace and minor occurrence, but possibly a fascinating opportunity for us to learn from.
    This post suggests that the impact flash would not be visible from Earth, but fortunately we have a number of probes available to collect data on-site. The projected impact site is even near to the area being explored by the Opportunity rover, although not so near that the rover itself is in danger. I wonder if it would be able to return any images of the event.

    Perhaps seeing the creation of a crater roughly this size by an object only 50 m across would remind governments of the importance of funding projects to survey the sky for objection which might impact Earth, such as the one which discovered 2007 WDS.
    I should note that 2007 WDS was discovered after its closest approach to Earth, as is often the case.

From APOD, quote: An unusual spot has been found on Mars that scientists believe is not natural in origin. The spot appears mobile and is now hypothesized to be a robot created by an intelligent species alien to Mars.

Cool! That Mars Reconaissance Orbiter sure has some high resolution.