Monday, March 15, 2010

Phobos Flyby

Images from the recent flyby of Phobos, on 7 March 2010, are released today. The images show Mars’ rocky moon in exquisite detail, with a resolution of just 4.4 metres per pixel. They show the proposed landing sites for the forthcoming Phobos-Grunt mission.
 

9 comments:

pimp-a-lot bear said...

kewl! I like the bumps.
I never knew it's such a small moon. Is it correct to state there is no lower limit for wat is considered a moon?

annom said...

I don't think there is an official limit, but I don't call the rocks in the rings of Saturn moons. They are natural satellites (=moon), but not moons imo :)
Earth is also a natural satellite of the Sun, but again no moon imo. Technically it probably is.

Also remember there is only one Moon.

pimp-a-lot bear said...

Hmmm.
So calling Phobos a moon is strictly speaking incorrect?

Are this Black and White pictures or does this moon have no color?

annom said...

No Phobos is a moon, but no Moon ;)
It's a natural satellite of a planet and has a serious size so I call it a moon.

I think they are near-infrared images shown as grey-scale. The phobos wiki has a more realistic colour view, using rbg and infrared. It's a bit reddish like Mars.

annom said...

cybrbeast may explain the lines on Phobos' surface.

cybrbeast said...

I wouldn't know how the lines formed, but apparently:
" The grooves seem to radiate in all directions from the giant Stickney crater and converge on the opposite side of the satellite at a region close to the Stickney antipode. "

I don't know if I'd call Phobos a moon. Phobos is has a mean radius of only 11.1km. Maybe only objects large enough to become sufficiently spherical should be considered moons.

annom said...

The lines may be from the impact ejecta; a continuous ejecta curtain.

cybrbeast said...

That might be Annom, though I doubt it because the lines spread across the entire body, so that means the ejacta must have orbited the body which seems unlikely because the escape velocity must be minuscule.
Also the lines look like depression to me, though that could be due to secondary cratering.
I don't know, maybe they are fracture or fault lines. Lets hope Phobos-Grunt finds out.

annom said...

Here is a paper about the grooves.