Messenger Discovers "Spider" Crater on Mercury

I Don't Believe in Imaginary Property brings us a Washington Post story which discusses how scientists are finding surprises among the pictures sent back from Mercury by the Messenger spacecraft. In particular, images depicting a crater with over 100 troughs radiating out from it are stumping researchers. The crater is referred to as 'The Spider', and it occupies a basin that has turned out to be larger than once thought. NASA also has a discussion of the crater. The Messenger craft began taking the up-close photos earlier this month. From the Post: "Scientists were also surprised by evidence of ancient volcanoes on many parts of the planet's surface and how different it looks compared with the moon, which is about the same size. Unlike the moon, Mercury has huge cliffs, as well as formations snaking hundreds of miles that indicate patterns of fault activity from Mercury's earliest days, more than 4 billion years ago."

Comments

Cosmic Water balloon

[LiquidCoooled]

Its a cosmic water balloon strike.
A comet impacted and splatted its matter all over.

Hmm...

[jwietelmann]

Is it the Great Stone Ass of Mars? http://www.gotfuturama.com/Multimedia/EpisodeSounds/3ACV10/09.mp3

Re:Hmm...

[audubon]

Looks like Uranus.

Evidence of Water!

[ErroneousBee]

Clearly, those are water channels running into the crater.

Obviously at some point Mercury was hollow and covered by an ocean, then an asteroid hits, punctures the surface, and the ocean drains into the center of the planet, creating the channels we see today.

Now, I know there are those who will say "but liquid water cant exist that close to the sun".
Well, to those people I say "Its not called Mercury for nothing".

It's Just amazing!

[DRAGONWEEZEL]

When I think about how far we have come, I am truly amazed. These pictures are from a flyby too! Imagine what we will get when this thing sits in orbit!

Faults from extreme tides, etc

[192939495969798999]

I thought the faults and crustal weirdness on Mercury was from the Sun's insane gravity warping and distorting the planet as it rotates and revolves around the sun (also - the super-hot temperature causes expansion on the hot side, compression on the cool side).

Re:Faults from extreme tides, etc

[TripMaster Monkey]

I wouldn't exactly call it "insane"...the Sun's tidal effects on Mercury are only about 17% greater then the Moon's tidal effects on Earth.

Re:Faults from extreme tides, etc

[nusuth]

That is incorrect, Mercury is not tidally locked with Sun. It is in 3:2 spin resonance with Sun, therefore the forces vary slowly (change direction twice for every three orbits) but they are not constant.

Looks less like spider

[jsheedy]

More like sperm.

Probably Moon was formed later

[anandsr]

I think the difference is due to their formation. Mercury I believe was formed naturally out of gas and elements like Earth, and so has volcanoes etc. While Moon is probably a breakaway part of earth, which got formed just before solidification of earth started. So that Moon never had a hot core, and so there was no volcanic activity.

Re:Probably Moon was formed later

[spacemandave]

Actually, you have that backwards. The Moon is covered in volcanic features. The dark "seas" are actually huge lava flood plains formed by volcanoes that were active for about a billion years after the Moon's formation. Mercury lacks these extensive volcanic features, likely because Mercury's crust is under compression making it harder for magma to break through and reach the surface. The compression is likely due to Mercury's massive iron core, which shrunk slightly as it cooled shortly after the planet formed.

Ground Control to Major Tom

[Ranger]

"The spiders are on not on Mars. Get your ass over to Mercury!"

Tidally Locked?

[DeeVeeAnt]

Oh no it isn't!
http://en.wikipedia.org/wiki/Tidal_locking#Planets
"Until radar observations in 1965 proved otherwise, it was thought that Mercury was tidally locked with the Sun. Instead, it turned out that Mercury has a 3:2 spin-orbit resonance, rotating three times for every two revolutions around the Sun; the eccentricity of Mercury's orbit makes this resonance stable. The original reason astronomers thought it was tidally locked was because whenever Mercury was best placed for observation, it was always at the same point in its 3:2 resonance, so showing the same face, which would be also the case if it were totally locked."

Great.

[imnojezus]

Now I get to have nightmares about "Mercurian Crater Spiders". Thanks Slashdot.

spider planet

[razorh]

Spiderplanet Spiderplanet does whatever a spiderplanet does...

The Shadows are comming.

[jellomizer]

It is a Shadow Ship. Hiding for thousands of years. Waiting for the year 2268

Re:The Shadows are comming.

[N1ck0]

Its clearly the impression of the Flying Spaghetti Monster. See for yourself the picture and indentations match perfectly.

After creating the universe he surely had to stop somewhere for a brief rest. And we all know that since the 1800 there has been an increase in discovering impact craters, colliding galaxies, planets, black holes, cosmic ray bursts, etc. These number of these events are also in inverse correlation to the amount of pirates remaining on earth. Thus this is proof that the 'pirate effect' is clearly not isolated to our planet.

My Forensic Opinion

[flyneye]

Just from what I can see,it looks as though perhaps Mercury isn't as solid underneath its crust as perhaps thought.It looks to me like it was hit causing compression,sunk,then pressure pushed back up causing the cracks which may or may not have guided lava.Mercury,a bad place to visit and I wouldn't wanna live there.

Reporter not paying attention

[L. J. Beauregard]

Scientists were also surprised by evidence of ancient volcanoes on many parts of the planet's surface and how different it looks compared with the moon, which is about the same size.

FAIL. Mercury has about 1.4 times the Moon's radius and 4.5 times its mass.