I get about 210 C for the sub-surface temperature near the equator, and about 120 C at 60 degree latitude- not quite so mild. The diurnal temperature variation will only persist a meter or so into the subsurface, because the dry, airless, regolith is extremely insulating.
John.
Full Version: Mercury Flyby 1
[...]
Just wondering if maybe Io might have a few spots where the subsurface temp would be room temperature. Of course, such spots may be moveable and temporary.
Talk about every other factor being horribly wrong, some on Io would be downright ghastly.
Talk about every other factor being horribly wrong, some on Io would be downright ghastly.
[...]
QUOTE (JRehling @ Feb 8 2008, 11:49 PM) 
It has to. Mostly, the surface is colder than Mars, but locally hot enough to melt rock. More likely isotherms surrounding caldera rather than "spots". But, yeah, good luck getting to those locations. That day spent in cruise between the orbits of Europa and Io will set up a real horrorshow before Io fills the window.
I have a very hard time imagining what it would be like on the surface of Io -- e.g., what would you be standing on if you landed? Or could you even stand up at all? I suppose a (rather sturdy) umbrella would be a good piece of apparatus to have...
[...]
QUOTE (JRehling @ Feb 8 2008, 03:49 PM)
That day spent in cruise between the orbits of Europa and Io will set up a real horrorshow before Io fills the window.
Why would it be a horrorshow? Just make sure you have some good radiation protection and/or man up.QUOTE (David @ Feb 8 2008, 08:59 PM)
I have a very hard time imagining what it would be like on the surface of Io -- e.g., what would you be standing on if you landed? Or could you even stand up at all? I suppose a (rather sturdy) umbrella would be a good piece of apparatus to have...
Well, that all depends on where you are. A good chunk of the surface is smooth plains covered in sulfur/sulfur dioxide frost. Think Antarctica, but yellower (but sometimes white-grey). Sometimes it would look like Iceland. But overall, you could, just as long as you have good radiation protection (NEVER leave home without that) and a good spacesuit.Just be aware of your surroundings: Don't be a plume fallout zone (imagine a light hailstorm), don't stand around in a lava lake, etc.
Before this thread ends its days, I thought I'd share a movie with you all.
This is a scrunched down version...I'll have to find somewhere to post the larger version.
Click to view attachment
Enjoy
Astro0
This is a scrunched down version...I'll have to find somewhere to post the larger version.
Click to view attachment
Enjoy
Astro0
QUOTE (Astro0 @ Feb 9 2008, 04:15 AM)
...I'll have to find somewhere to post the larger version.
Click to view attachment
Click to view attachment
Astro0, try www.vuze.com. The people behind the Azureus BitTorrent client run this site.
A new release:
http://messenger.jhuapl.edu/gallery/scienc...mp;image_id=161
lots of evidence for lava flows. Mercury seems to come a bit more to life with these kinds of explanations.
http://messenger.jhuapl.edu/gallery/scienc...mp;image_id=161
lots of evidence for lava flows. Mercury seems to come a bit more to life with these kinds of explanations.
QUOTE (remcook @ Feb 14 2008, 03:20 PM)
Mercury seems to come a bit more to life with these kinds of explanations.
Speaking about life...
What's that feature casting a shadow at the blue arrow's end? Mercury's MegaFoot?...
An interesting oblique view of craters in the Caloris basin was released yesterday:
Craters in Caloris
It nicely brings home the fact Mercury's topography is more subdued than on the Moon, take note of the horizon in particular.
Craters in Caloris
It nicely brings home the fact Mercury's topography is more subdued than on the Moon, take note of the horizon in particular.
That is true, though not surprising, since it has a mass similar to that of Mars.
Another very nice new release at the Messenger site:
http://messenger.jhuapl.edu/gallery/scienc...mp;image_id=174
Fractures in Caloris. The first releases didn't show the real level of detail we would get inside Caloris. Also, the bright halo feature I noted on here earlier was described at LPSC as a probable volcanic vent, and a few others were noted. An interesting place!
Phil
http://messenger.jhuapl.edu/gallery/scienc...mp;image_id=174
Fractures in Caloris. The first releases didn't show the real level of detail we would get inside Caloris. Also, the bright halo feature I noted on here earlier was described at LPSC as a probable volcanic vent, and a few others were noted. An interesting place!
Phil
That new image is a really interesting one, Phil. Not only are there a lot of extensional graben, there are many different flow features. The main flows in which the majority of the fresh-looking graben are cut have definite flow boundaries along the lower left of the image, trending up and to the left.
The most interesting thing to my eye are the filled-in grabens as you approach the large dark-rim-ray crater in the upper right. If you look carefully, you can see hints of a lava flow front overlaying the main, cracked flow that makes up a majority of the scene. It is above and to the right of this subtle flow front that we see a number of filled-in and "ghost" graben.
So... there must have been lava flows in Caloris *after* the uplift that formed the graben. That's *very* interesting...
-the other Doug
The most interesting thing to my eye are the filled-in grabens as you approach the large dark-rim-ray crater in the upper right. If you look carefully, you can see hints of a lava flow front overlaying the main, cracked flow that makes up a majority of the scene. It is above and to the right of this subtle flow front that we see a number of filled-in and "ghost" graben.
So... there must have been lava flows in Caloris *after* the uplift that formed the graben. That's *very* interesting...
-the other Doug
There is a new article in press in Icarus titled: "Radar imagery of the southern Caloris region, Mercury" by John K. Harmon. This paper covers RADAR mapping from Arecibo of the area on Mercury between 172 W and 228 W, and 22 S and 32 N. This area covers much of the terrain seen by MESSENGER in January. The southern part of the Caloris basin is clearly visible. In that basin, and comparing to the graphic at http://messenger.jhuapl.edu/gallery/scienc...ics/Strom01.jpg , the two-ring impact crater at lower center, the "spider" crater, and the ray crater to the west of the "spider" crater are clear visible. At least two of the troughs (both trending NW-SE) are visible at the spider crater. No clear rays are visible at the ray crater in the radar map, though Harmon was right in suggesting that this was a fresher crater based on the bright halo around it. The two-ring crater has two rings, though from the text, he seemed to only consider the inner ring as a crater, though he does suggest that it is a two-ring impact basin.
New article in space.com describes how Mercury's cliffs seem aligned N-S. This is attributed to thin mantle shell convection.
http://www.space.com/scienceastronomy/0803...ury-cliffs.html
-Mike
http://www.space.com/scienceastronomy/0803...ury-cliffs.html
-Mike
During the post-Mariner analysis days, there was considerable effort to determine the latitude distribution and any preferred orientation of the scarps. Mercury was <is?> modeled as an initial ?normally? fast rotator (like Earth and Mars) that underwent tidal de-spinning till it was caught in the 3/2 resonance it's in today. The equator would have been spread out a bit and the poles sucked-in and flattened a bit. Despinning the planet should have resulted in crustal compression at the equator and stretching at the poles, with the stress at the equator being decidedly directional.
The models looked at the effects of the competition between despinning and relatively faster or slower global contraction on global stress patterns and resulting global faulting patterns. In some models, you'd see the effects balancing out at some latitudes resulting in no scarps or fractures, in other models, there's be scarps at some latitudes and graben <not seen> at others. There would also be directional orientations of the scarps at some latitudes.
As I recall, the Mariner data showed little global variation in scarp abundance or orientation within the two low-to-moderate sun-angle zones where surface relief was well imaged.
It's unclear to me whether some global variation was eventually teased out of the Mariner data or has only become apparent when much of the Mariner hi-sun-angle zone was imaged at lower sun angles and an entirely new longitude range was imaged with good illumination. Either way, there seems to be no mention of the old model work in the new analysis with mantle convection stress added to global contraction stresses in the press-release and media coverage of the new model work that I've seen.
The emergence of geophysically meaningful planetary convection modeling on computer since the Mariner analysis days has resulted in the addition numical simulation experiments like these to planetary geophysics. Impressive capabilities, indeed!
The models looked at the effects of the competition between despinning and relatively faster or slower global contraction on global stress patterns and resulting global faulting patterns. In some models, you'd see the effects balancing out at some latitudes resulting in no scarps or fractures, in other models, there's be scarps at some latitudes and graben <not seen> at others. There would also be directional orientations of the scarps at some latitudes.
As I recall, the Mariner data showed little global variation in scarp abundance or orientation within the two low-to-moderate sun-angle zones where surface relief was well imaged.
It's unclear to me whether some global variation was eventually teased out of the Mariner data or has only become apparent when much of the Mariner hi-sun-angle zone was imaged at lower sun angles and an entirely new longitude range was imaged with good illumination. Either way, there seems to be no mention of the old model work in the new analysis with mantle convection stress added to global contraction stresses in the press-release and media coverage of the new model work that I've seen.
The emergence of geophysically meaningful planetary convection modeling on computer since the Mariner analysis days has resulted in the addition numical simulation experiments like these to planetary geophysics. Impressive capabilities, indeed!
Mozart Crater and surrounding plane (1973).
Mozart Crater and surrounding plane (2008).
It's interesting how different it looks in different lightning conditions.
Mozart Crater and surrounding plane (2008).
It's interesting how different it looks in different lightning conditions.
[...]
It really doesn't look that different. It is over the terminator in the view Peter posted, and the label is out in the smooth plain. Still, low light does create interesting effects. Here it is over the terminator but not by much.
Click to view attachment
Click to view attachment
Steve Albers updated his Mercury map.
You can download it from http://laps.fsl.noaa.gov/albers/sos/sos.html#MERCURY
You can download it from http://laps.fsl.noaa.gov/albers/sos/sos.html#MERCURY
Impact craters om mercury are named after dead poets and musicians,
I would like to see a newly imaged impact crater named after jim morrison of the doors perhaps the crater in the middle of the spider?
I would like to see a newly imaged impact crater named after jim morrison of the doors perhaps the crater in the middle of the spider?
QUOTE (infocat13 @ Apr 2 2008, 03:07 PM)
Impact craters om mercury are named after dead poets and musicians,
I would like to see a newly imaged impact crater named after jim morrison of the doors perhaps the crater in the middle of the spider?
I would like to see a newly imaged impact crater named after jim morrison of the doors perhaps the crater in the middle of the spider?
I vote David Bowie. ("Spiders on
QUOTE (Juramike @ Apr 2 2008, 09:20 PM)
I vote David Bowie. ("Spiders on Mars Mercury")
That one is still alive, fortunately...and that is a great tribute from Messenger! Here are my imediate thoughts...Rimbaud, Thoreau, Pessoa, Torga, Poe, Coubain, Hesse, Kerouac, Ian Curtis, Whitman, Twain, Dante, kavafis, GOETHE!
Let me think about it... ;-)
And this just gave an idea...
Now I went looking for more...:
Kipling!
Freddie MERCURY!
Joplin!
Hendrix!
Wagner and all the classics...Bach on the lead...
There so M-A-N-Y!
QUOTE (ustrax @ Apr 2 2008, 03:29 PM)
That one is still alive, fortunately
Ooops, right-o. How about Ziggy Stardust? (David Bowie's alter ego at the time). Does a past artistic persona count?
(Then we could also use Picasso's "Blue Period" for one of the spectrally fresher craters.)
Nice image of Beagle Rupes! [Just saw that is also in the caption... *Tsk tsk*]
BTW, the Spider shall hence forth be known as "Parthenon Fossae". The crater on top of it shall now be known as Apollodorus.
That is all.
BTW, the Spider shall hence forth be known as "Parthenon Fossae". The crater on top of it shall now be known as Apollodorus.
That is all.
Nice pic!
"BTW, the Spider shall hence forth be known as "Parthenon Fossae"."
This is what everybody was saying at LPSC, but now it has morphed into Pantheon Fossae.
Phil
"BTW, the Spider shall hence forth be known as "Parthenon Fossae"."
This is what everybody was saying at LPSC, but now it has morphed into Pantheon Fossae.
Phil
<thunk!> (Jaw hits floor) Incredible! Those HAVE to be more then mere impact features!!!
Looks at that big white splat to the NE of Kertesz as well. The subsurface seems to be much more regionally differentiated then originally thought.
Looks at that big white splat to the NE of Kertesz as well. The subsurface seems to be much more regionally differentiated then originally thought.
[...]
QUOTE (JRehling @ Jun 3 2008, 07:57 PM)
I think we'll end up concluding that the subsurface of one area of Mercury is lighter than some other area for similar reasons to why Syrtis Major is darker than the areas around it -- it's just where that particular stuff happened to bubble up.
I hope there's no-one here from the Sun newsdesk...
Steve Albers has been updating his global map
http://laps.noaa.gov/albers/sos/sos.html
Messenger wide angle camera images included in his Mercury map
http://laps.noaa.gov/albers/sos/sos.html
Messenger wide angle camera images included in his Mercury map
New images !
Basin Dürer (beautiful oblique view)
and
Cunningham Crater in Old Caloris Basin
Does anyone know when will be next PDS data release ? (the last release was in January 2008)
Basin Dürer (beautiful oblique view)
and
Cunningham Crater in Old Caloris Basin
Does anyone know when will be next PDS data release ? (the last release was in January 2008)
The Caloris image is full of interest, but what I hadn't noticed before was that little 'ice cream cone' shaped crater chain in the bottom third of the image terminating in a tiny, but bright crater...
P
P
The folks at APL have put up a really nice web site showing the visual data and timeline of the first flyby. Its at:
http://messenger.jhuapl.edu/encountersactual/
I like how it shows the Planned view, and then what they actually got.
The data is in the PDS. Space Daily has an article about it at:
http://www.spacedaily.com/reports/Mercury_...System_999.html
http://messenger.jhuapl.edu/encountersactual/
I like how it shows the Planned view, and then what they actually got.
The data is in the PDS. Space Daily has an article about it at:
http://www.spacedaily.com/reports/Mercury_...System_999.html
A new image (actually, the last from Mercury 1) posted 2 days ago.
I was just going to point that out. Here's a version enlarged and processed to bring out relief near the terminator - showing a bit of rotation since the big mosaic was made earlier.
Phil
Click to view attachment
Phil
Click to view attachment
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