The Mercury MESSENGER probe folks just released a new cool image, and this one shows one fo the larger craters on the planet that has a dark ring around it. Emily has lots of details, of course, with an explanation… but I know the real cause of these rings. You’d have dark circles around your eyes too if the Sun were constantly shining in your face.
P.S. My buddy Chris Lintott is hosting the Carnival of Space this week, too.










February 21st, 2008 at 4:45 pm
Sun constantly shining? Mercury isn’t tidally locked 1:1. Am I missing something here or do I just lack a sense of humour?
February 21st, 2008 at 5:26 pm
‘f course, that mostly affects individuals with thin skin. So are you suggesting that the messenger of gods doesn’t have (to be gifted with) a particularly thick crust? I seriously doubt this is a fruitful way to do astronomy. (Or medicine. Or mythology.)
Btw, what would we make of all the craters and wrinkles? Bad impact of youth acne followed by premature aging due to too much sun exposure?
February 21st, 2008 at 5:52 pm
Hello! I’m from Argentina, and I just found this great blog!
I have a question:
What size have those little craters, that looks like dots in the image? 2-3 meters, prehaps?
Thanks!
February 21st, 2008 at 6:20 pm
Huh. And here I thought that the Mercury Messenger was a minivan. Y’learn something new every day.
February 21st, 2008 at 7:09 pm
@Fer Probably not, I don’t know the actual numbers, but you should look at these similar craters, it points out the “smaller” ones as 1 mile!
http://www.nasa.gov/mission_pages/messenger/multimedia/phone_crater.html
It’s just that we are not used to think on those scales, but we can try
February 21st, 2008 at 8:06 pm
Wayne: To answer your question: Yes, you’re lacking a sense of humor. The joke is simply that Mercury is so dang close to the Sun, and since, like most planets, it has no arms, it is unable to apply sunscreen to itself. In fact, those dark areas may well be basal cell carcinoma. Only someone who majored in astronomy with a minor in dermatology can tell for sure.
Mercury does rotate, albeit rather slowly. It takes the planet almost 59 Earth days to make one rotation on its axis.
February 21st, 2008 at 9:47 pm
Phil,
You’re a blithering genius. Do you ever get sick to death of your own voice?
John
February 21st, 2008 at 11:18 pm
I love seeing new pictures like that, thanks Phil.
February 21st, 2008 at 11:44 pm
Via Lugosi’s link above:
Wooooooooaaaaaahhh Ceiling Cat! The sun stands still, then moves backwards in the sky! Have scientists discovered the site of the Biblical Jericho? Then the Bible is literal fact after all……… except that the Old Testament happened on a different planet…….
No, wait…….. In space no one can hear you blow your ram’s horn………
False alarm!
We now return you to your regularly scheduled skeptical frame of mind already in progress.
February 22nd, 2008 at 12:36 am
sorry guys but this photo is as drab and blah as it can get..who knows whereinhell it really is?
February 22nd, 2008 at 5:18 am
“Mercury just needs some rest”
groan…
now, this truly is BAD astronomy!

Going on vacation for a week, man, I’ll miss this blog. Dr. Plait, keep up the good work.
The rest of you, just make sure that Huckabee isn’t declared Prez and replaces the NSF by the Disco ‘Tute!
February 22nd, 2008 at 6:17 am
I’m guessing the dark color may have been to material thrown off by a dark-colored impactor. That or something is sputtering dark material around that spot and no other. Is it possible that there’s some kind of low-level volcanic activity on Mercury, possibly driven by tidal heating?
February 22nd, 2008 at 9:23 pm
I see Bigfoot near the center of that big crater!
February 24th, 2008 at 3:04 am
Just a reminder that Mercury is currently very easy to find in the pre-dawn sky.