More Mercury awesomeness from MESSENGER:
Wow, this one is very high res (click to embiggen)!
It was taken when MESSENGER was less than 6000 km over the surface, and shows crushing detail near Mercury’s equator (the smallest things you can see are about 300 meters across, roughly as detailed as you get looking at the Moon through a big earthbound ’scope). The whole image is about 170 km across.
There are so many things to see! The huge crater at the lower right is interesting. I’m not sure what crater it is, or if it was even mapped by Mariner 10 back in ‘74; I’m still figuring out how to match up the maps. I’m guessing the crater us about 200 km across. We only see one quadrant of it here, but there’s lots of stuff to note. The rim is incredible, seen in great relief due to the low sun angle.
The floor of the crater is relatively flat, so I suspect some later event filled it in, maybe volcanic flow. Then, over time, more asteroid impacts created the peppering of tiny craters all over it. But the floor is also cracked, which doesn’t surprise me too much. Cracks like that are all over the tiny planet, possibly due to the crust shrinking as the planet’s core cools and shrinks. That right there is fairly mind-boggling.
The linear radial features — the lines coming straight out of the center all around the crater — are probably secondary events, streamers of rocks that splashed out of the crater when the impactor hit. They slam back into the surface and create littler craters.
Heh. At the top is a biggish crater, and you can just see a little crater inside it, with its rim poking out into the sunlight.
Now, I’m not geologist, I’m just a country astronomer, but if I can see this stuff at a glance, I’m guessing people like Emily are having braingasms right now. And this is just one of three high-res images they just downloaded! I’d love to be at the data center at APL right now.
Fun fun fun. And more to come!
January 16th, 2008 at 6:14 pm
Oh, that one in the upper-left corner! You can see the rebound peak in the center! This is so awesome, in the old, literal sense of the word, not like how hot dogs are awesome, but more inspiring-awe-type awesome.
January 16th, 2008 at 6:21 pm
OK, here’s a science-outreach kind of question. For casual friends who are intrigued by things like possible life on Europa and the lakes of Titan but find these new Mercury photos, well, rather boring (”It just looks like the moon; it’s dead, dead, dead”) and wonder why NASA “wasted” so much money on Mercury when there are “more interesting” places to explore in the solar system, what do I tell them? I mean, even *I’m* looking at these and thinking, “yeah, that’s cool that we haven’t seen these areas before, but it’s not a very dynamic place”.
Anyone give me two or three quick sound-bites on the most important things to know about why the MESSENGER mission is big news?
January 16th, 2008 at 6:21 pm
“The linear radial features — the lines coming straight out of the center all around the crater — are probably secondary events, streamers of rocks that splashed out of the crater when the impactor hit.”
You are completely wrong. They are actually roads built by an ancient civilization. The small dots clustering around the end of them are obviously glass spirals. Man, how did you get that so wrong?!
Seriously though, these kinds of pictures give me the chills. Science totally rules.
January 16th, 2008 at 6:46 pm
@DavidHW
Basically, you are asking “why Mercury?”
Take a look at http://messenger.jhuapl.edu/why_mercury/index.html
By learning about why Mercury is the way it is, we learn more about how planets behave. Thus we learn about how Earth might behave.
Also, going to other planets (even unmanned missions) ranks pretty high up on the awesomeness meter.
January 16th, 2008 at 6:50 pm
[...] The Bad Astronomer wrote an interesting post today on More Mercury!Here’s a quick excerptPicture of Mercury from MESSENGER. Wow, this one is very high res (click to embiggen)! It was taken when MESSENGER was less than 6000 km over the surface, and shows crushing detail near Mercury’s equator (the smallest things you can see … [...]
January 16th, 2008 at 6:54 pm
Holy crap! I think I see Jesus in that picture!
January 16th, 2008 at 6:56 pm
DaveR:
D’oh! Looks like NASA anticipated the “Why Mercury?” question well in advance.
Thanks.
January 16th, 2008 at 7:11 pm
How come we’ve only started exploring Mercury now?
I was reasonably sure NASA sent probes to every planet in our solar system. I mean there are only 8 we actually have to explore. What the heck were those Pioneer missions all about?
‘Hey let’s launch some probes out into deep space for no good reason’
‘But what about sending a probe to Mercury?
‘Screw Mercury! It’s the planetary equivalent of a retarded half-brother!’
‘As you wish Dr. Sagan’
January 16th, 2008 at 7:12 pm
Check out the incredible chain of overlapping craters on this pic: http://tinyurl.com/yo8tmv
Fascinating!
January 16th, 2008 at 7:33 pm
[...] More Mercury! By The Bad Astronomer Now, I’m not geologist, I’m just a country astronomer, but if I can see this stuff at a glance, I’m guessing people like Emily are having braingasms right now. And this is just one of three high-res images they just downloaded! … Bad Astronomy Blog – http://www.badastronomy.com/bablog [...]
January 16th, 2008 at 7:36 pm
Hoonser: Because Mercury is close enough to the sun that an orbiter would get fried just trying to get there (all those loops and close passes to the sun, not to mention staying in orbit of Mercury for that long). I seem to recall reading somewhere (possibly here:P) that it was only recently that the materials necessary to construct such a probe were invented, which is why a Mercury orbiter is only happening now.
As Fill says in his post, there was at least 1 Mercury flyby mission that took pictures of part of the planet before: Mariner 10.
January 16th, 2008 at 7:45 pm
I have a question for those who know- how deep would you have to dig into the Mercurian surface before temperatures would be cozy for humans even when the sun was beating down outside- deep enough for a colony to be built?
I’m guessing that in the future, Mercury will be home to a huge metal mining operation.
Jess Tauber
January 16th, 2008 at 7:52 pm
Wow! That is really… reallly… um… *sigh*
Not much different from the Moon.
I’m so old and jaded.
— I’m guessing that in the future, Mercury will be home to a huge metal mining operation.
In the Transmetropolitan graphic novels, it’s mentioned that Earth is powered by the energy transmitted from Mercury, which has been completely covered by solar panels.
http://en.wikipedia.org/wiki/Transmetropolitan
Highly recommended. Great satire on politics, media and journalism.
— I was reasonably sure NASA sent probes to every planet in our solar system.
Mariner 10 in 1975 was the first to Mercury.
January 16th, 2008 at 8:14 pm
Around 3 o’clock about half way from the center to the edge I see a human skull!
you can see one eye socket and the upper jaw, the other eye and lower jaw are in shadow.
January 16th, 2008 at 9:26 pm
Looks like the Messenger image site is taking a beating — I’m getting a string of “The connection has timed out” errors. Guess I’ll wait until the astronmers go to bed … erm . Hm. That might be a long wait!
January 16th, 2008 at 9:50 pm
Amazing. The MESSENGER site seemed to imply these were never before seen regions or at least regions that Mariner 10 missed. What’s the story on that? Are we looking at never before seen regions of Mercury?
This stuff is truly amazing, I remember watching it launch and thinking, “man, that’s gonna take forever to get there”. How fast time goes by.
Good stuff as usual, thanks Phil.
January 16th, 2008 at 9:50 pm
Wicked Awesome pics. And yeah, we geologists are real excited. But I especially love the use of the word “embiggens” by Phil (Plaitt). Love It! Embiggens is a perfectly cromulent word, and really should be used more often in society.
January 16th, 2008 at 10:11 pm
So it seems like there’s a lot of “crater chains” in these pictures. Are these features also seen on the Moon, or any of the other heavily cratered bodies in the solar system?
January 16th, 2008 at 10:21 pm
That’s not just awesomeness, that’s awesomenessosity!
January 16th, 2008 at 10:30 pm
Phy,
Yes, there are crater-chains on other bodies, including the Moon. They’re probably created by asteroids which disintegrate (due to tidal forces; see “Roche limit”) as they approach.
January 16th, 2008 at 10:30 pm
How come we’ve only started exploring Mercury now?
I was reasonably sure NASA sent probes to every planet in our solar system.
It’s really hard to get to Mercury. A probe can’t just flit around like the Starship Enterprise. Once it’s escaped from Earth orbit, it finds itself in orbit around the Sun, and its orbit is similar to that of the Earth. We can use rockets to change the orbit, but that can take a lot of fuel.
Basically we have to shorten the low side or perihelion of the orbit, and then shorten the high side or aphelion. It’s a bit more complicated than that, but the basic idea is that a thrust counter to the probe’s motion shortens the other side of the orbit. That thrust can come from a rocket or from “slingshotting” the probe in front of a planet. This pass by MESSENGER didn’t just get some photos and other science data; it also slowed the probe down a bit. They’ll have to do that two more times, along with some more burns of the main thruster, before MESSENGER is moving slowly enough to end up in orbit around Mercury.
And we had sent probes to all the “official” planets. Mariner 10 took three passes by Mercury in 1974 and 1975.
January 17th, 2008 at 12:38 am
Totally off-topic, but I just got back from seeing Cloverfield (it opened today here in New Zealand). It is awesome. Intense and awesome.
January 17th, 2008 at 1:58 am
Since Phil so deftly described how researchers get use of the Hubble, I’m curious about this probe. Is there info/data that non-NASA, interested parties have to apply for or wait in line for, or is the info all inferred from high res photos and, therefore, publicly available? (I clicked around a bit but it’s probably faster to just ask here!).
January 17th, 2008 at 4:31 am
Quiet Desperation writes:
[[In the Transmetropolitan graphic novels, it’s mentioned that Earth is powered by the energy transmitted from Mercury, which has been completely covered by solar panels.]]
Except that there’s this thing called “the inverse-square law…”
January 17th, 2008 at 5:50 am
Truly amazing!
Now Mercury seems more like a place then ever before. The iron planet is bound to have surprises in store for us.
An image at THIS range could be confused for the lunar surface. Funny, isn’t it? From a distance, you can distinguish the two, but not up close (least, not without prior knowledge). Sort of oppisite of what you do with people.
Perhaps this could inspire a contest in the future, as more close-ups of Mercury arrive. Show images of Mercury randomly mixed with orbital images of the moon. Then, see how many can tell the two apart. Fun!
I wonder if the company Mercury knows of their namesake’s new fame (okay, it was the god they were named after. But the planet was the inspiration for the name!).
January 17th, 2008 at 6:26 am
Yep. There’s no doubt that Mercury is visually uninspiring. Kind of like the Sacramento of the solar system. So it’s a harder sell justifying the mission to the public since you’ve got to talk about the usefulness of the data without lots of pretty pictures like you’d get with many other bodies.
January 17th, 2008 at 7:00 am
…Visually uninspiring? Allow me to disagree there. It’s BEAUTIFUL. Absolutely gorgeous.
That full image of Mercury is now my wallpaper.
January 17th, 2008 at 7:19 am
Does NASA or anyone else have any future plans for a Mercury lander? Or is Mercury considered to be too much like the earth’s moon to bother with such a thing?
Also, what apparent motion of the sun would an observer see located on Mercury? With an orbital period of 88 days and a rotation period of two thirds of that (i.e., 59 days) I believe that means that the apparent length of the day on Mercury is about 176 days. But does the sun rise in the east like on Earth or the west? Also, with an orbital eccentricity of 21 percent I wonder if there are any retrograde motions of the sun in the Mercurian sky.
January 17th, 2008 at 7:25 am
Is it really so moon-like looking? Are those images b/w or is it really so colourless? In Mariner 10 pics I assumed they were b/w, but now, here we go and… more b/w! I expected some little surprise about.
January 17th, 2008 at 7:51 am
So, anyone else notice the portrait of Coco at the bottom-center of the image?
http://images.google.com/imgres?imgurl=http://bp0.blogger.com/_Q55l_ERG5SI/RsIwWHTgkqI/AAAAAAAAAII/Ho4cnsoWxL8/s320/coco1%255B1%255D.jpg&imgrefurl=http://gypsydoodlebug.blogspot.com/2007/08/one-word.html
http://gypsydoodlebug.blogspot.com/2007/08/one-word.html
(Or is that just another Jesus image?)
January 17th, 2008 at 8:03 am
From Dr. BA’s original post:
From the page at the Messenger site:
So I guess that’s a “no”.
January 17th, 2008 at 8:16 am
Tom Marking:
(What is a day on Mercury?)
I don’t know if this helps or hurts in answering your question:
http://btc.montana.edu/messenger/Interactives/ANIMATIONS/Day_On_Mercury/day_on_mercury_full.htm
Note how, near perihelion, the Sun’s motion appears (”is”?) retrograde in the sky, due to the speed at which Mercury is moving. (I remember reading this years ago, but this animation makes it quite clear.)
A longer description of the animation is here:
http://www.sciencenetlinks.com/tools.cfm?DocID=72&Grade=6-8
January 17th, 2008 at 8:26 am
off topic -
http://www.jmccanneyscience.com/
Anyone dipped into this guys work (he seems to be yelling at us in italics…and…using….a lot of …. continuous …. grammar….. techniques…..and offering us NO ANSWERS TO HIS CLAIMS, despite his caps lock syndrome).
January 17th, 2008 at 8:41 am
http://www.badastronomy.com/bad/misc/mccanney/index.html
That guy, Monkey?
January 17th, 2008 at 9:02 am
@Barton Paul Levenson:
(On the concept of Mercury being covered in solar panels and the energy being transmitted to Earth)
A) It’s a comic book. Suspend your disbelief.
B) Suppose, for a second, such a plan were to be considered. Could you transmit the energy via some sort of tight collimated beam (e.g. a laser or maser)? I say this not knowing anything about Mercury’s orbit relative to the Earth, but that particular problem is solvable, I think.
January 17th, 2008 at 9:37 am
@chris:
I didn’t know there was anyone else here from New Zealand! I’m looking forward to seeing Cloverfield, too. The TV ads look really good.
January 17th, 2008 at 9:52 am
Ken B, Wow! That animation is way cool. You can actually see Mercury stop in the sky and go backwards. I particularly like the surface temperature gauge. Let me see if I can do a back-of-the-envelope calculation to convince myself that this retrograde motion is correct:
Average distance of Mercury from the sun = 57.9 million kilometers
Orbital period = 87.97 days
Rotation period = 58.65 days
Average orbital velocity = 4.14 million kilometers per day
Average angular velocity of sun due to rotation = 6.14 degrees per day
Average angular velocity of sun due to orbit = 4.09 degrees per day
So on average to compute the time from sunrise to sunrise on Mercury you subtract 4.09 from 6.14 getting 2.05 degrees per day or 360 degrees per 175.6 days.
But, that’s just the average. The orbit is highly elliptic.
Eccentricity of orbit = 0.206
Perihelion distance = 0.794 * 57.9 million kilometers = 46.0 million kilometers
Perihelion orbital velocity = 1.206 * 4.14 million kilometers per day = 4.99 million kilometers per day
Angular velocity of sun due to orbit at perihelion = 4.99 / 46.0 = 0.108 radians per day = 6.22 degrees per day
So at perihelion the apparent motion of the sun in the sky is 6.14 – 6.22 or -0.08 degrees per day. That’s a negative number so the sun appears to move backwards (west to east) at a very slow rate of speed, so it will appear almost stationary near perihelion, just like the animation says.
Joshua 10:13 – “And the sun stood still, and the moon stayed, until the people had avenged themselves upon their enemies. Is not this written in the book of Jasher? So the sun stood still in the midst of heaven, and hasted not to go down about a whole day”
This is a common occurence on Mercury, not a miracle.
January 17th, 2008 at 9:53 am
Connect the dots la la la la Connect the dots la la la la
January 17th, 2008 at 9:53 am
Jeffersonian,
My guess is that, since MESSENGER is a publicly-funded (non-classified) project, all data are in the public domain. This isn’t to say of course that you wouldn’t have to do some extensive legwork to get hold of the data, especially the non-photographic stuff. For instance, if you want to study the planet’s mass, you’ll need to get all the flight dynamics data, which would consist entirely of reams of numbers telling how the spacecraft’s velocity changed as it grazed Mercury. You also might be asked to pay for the expense of generating a copy of the data. But I’m sure that it’s there for the asking.
January 17th, 2008 at 9:55 am
Connect the dots la la la la Connect the dots la la la la
http://www.moostangproductions.com/temp/other.gif
January 17th, 2008 at 2:10 pm
Digging into Mercury, unless at the poles, won’t ever make it cool enough to survive. Underground will simply average out the sunlight, making it hot year-round.
January 17th, 2008 at 2:21 pm
Quiet Desperation says: ” ‘— I’m guessing that in the future, Mercury will be home to a huge metal mining operation.’
In the Transmetropolitan graphic novels, it’s mentioned that Earth is powered by the energy transmitted from Mercury, which has been completely covered by solar panels.”
Don’t forget “Runaround”, one of Asimov’s robot stories.
- Jack
January 17th, 2008 at 2:57 pm
Dude, you really should learn about geology. I think you’d dig it!
January 18th, 2008 at 11:05 am
Clearly, it’s Kang (or Kodos) in that image.
http://www.hvcomputer.com/temp/mercury.html
January 19th, 2008 at 3:19 am
With the pictures of Mercury now coming in, I find it striking (no pun intended) that many of the craters have central rings or craters — many more than our Moon has.
I haven’t heard any comments about it yet, but they seem similar to the morphology of the craters on Ganymede (one of the moons of Jupiter):
http://img375.imageshack.us/img375/9899/ganmogac4gs.jpg
Here’s a picture of Mercury:
http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/EW0108829708G.4release.jpg
Now, Ganymede is rock and ice, but I’m not implying that Mercury is. But Ganymede may have a large rocky core topped by a rock-ice layer that the craters are in (although way more ice than the inner Galilean moons), and Mercury certainly has a large core (although made of iron). I’m suggesting that the central crater/ring is a seismic “bounce” in some way off the core from the impact.
On the Moon, craters that are small don’t have central peaks. As the craters get larger, they develop central peaks. For even larger craters, you can get double or more complicated central peaks and the largest have central rings. (Mercury has lots of craters with central peaks, too — I’m just suggesting that Mercury has MORE craters with central craters than it “should have” and wondering about the reason.) But the Moon also has a very small core.
Mercury’s surface is also saturated with craters, like Callisto’s — another moon of Jupiter:
http://astrored.org/astrofotos/albums/Sistema_Solar/Jupiter/callisto.jpg.html
Look how many craters are there, and most seem to have central craters! Callisto is thought to have an even larger core than Ganymede, but the saturation of large numbers of craters indicates a very OLD surface (nothing’s come by to erase the craters over the age of the Solar System.
This stuff is amazing to me . . .
BTW, for those interested, here’s a website that predicts sizes of craters on the Earth from various impacts:
http://www.lpl.arizona.edu/impacteffects/
— Steve >>>>
July 28th, 2008 at 8:07 pm
The near stationary appearance of the sun at Mercury’s perihelion is no accident. Mercury’s aphelion is 1.5 times its perihelion distance, and since tidal forces are inversely proportional to the cube of distance, the solar tides at perihelion are 3.5 times larger than at aphelion. So Mercury’s rotation is locked to the sun, but locked to the sun at perihelion, since the tidal forces are so much stronger then. We used to think Mercury was locked to the sun like the Moon is locked to the earth, but it’s a more complex kind of lock.