Radar And Mariner 10, Best possible mapping, pre-Messenger Options

[JRehling]

[...]

[Decepticon]

http://www.lpl.arizona.edu/~rhill/alpo/mer...f/messenger.pdf


Maybe this?

Page 5?

[Decepticon]

http://www.psrd.hawaii.edu/WebImg/HarmonRadarFig2.jpg

http://images.google.ca/imgres?imgurl=http...2005-12,GGLD:en

[lyford]

http://www.psrd.hawaii.edu/WebImg/HarmonRadarFig2.jpg
http://images.google.ca/imgres?imgurl=http...2005-12,GGLD:en

Awesome! Love the possiblity of ice in the polar craters -



I guess it's only fitting to have water on Mercury, if we have mercury in our water here....

[JRehling]

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[tedstryk]

(Added detail: One of the major methodologies in high-resolution radar mapping produces an image which reflects details over a line which is near the equator, so the result is not a flawless hemispheric image, but an image which shows the north and south hemispheres ambiguously overlapped, so that you can say with confidence that each feature so detected is either in the northern OR southern hemisphere, but you can't be sure which! This ambiguity can be eliminated with repeat observations, with slightly changed geometry, which will cause the overlapping to happen at a different angle, revealing which hemisphere a feature is really in. I'm not sure if this final step has yet been performed, but the conference abstracts describing the work do not mention the ambiguity problem.)


I imagine that optical data could help - in other words, if there is a bright feature with rays extending from it in one hemisphere, and there is clearly a well defined, young looking (not overlapped by anything) impact crater in one hemisphere or the other, the optical data could help resolve the situation.

[JRehling]

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[Phil Stooke]

I too am interested in this topic of pre-Messenger mapping of Mercury, in one of my many guises, as a historian of planetary cartography. One interesting aspect of cartographic history is the progression of mapping of a world from mission to mission... from pre-mission planning maps to the initial post-mission maps to assist initial data analysis, to the most advanced maps which summarize mission results, including relief, topography where appropriate, and geological maps. Mariner 10 didn't use a pre-mission map in the sense that Mars missions did, but there was a preliminary post-mission 1:25,000,000 scale map, and then the set of 1:5,000,000 scale quads and a new 1:15,000,000 global map. (and a lot more outside this very basic framework, such as the unpublished global map showing only the first encounter results).

Yes, I'd love to see a good pre-mission map. You are right, JRehling, it could be done. I'd love to see your work on this, actually. But one problem is that the radar data are almost always treated as traditional astronomical data, belonging to the scientists who obtained them, not as typical planetary data which are made public (almost immediately these days in some cases, and in compressed form). We planet types are spoiled! But the radar people have never released things very readily, one exception being the "pre-Magellan" CD-ROM with some venus and lunar radar data. An awful lot of radar data never even gets adequately published either.

Could your maps go up on a free image hosting service, with a URL in a post here?

Phil

[JRehling]

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[Bob Shaw]

The mercury maps are astonishing at this stage in the game! Terrific effort!

Can you post the link to the 8" amateur images?

[JRehling]

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[Bob Shaw]

Thanks!

[Chmee]

These are great images obtained from the ground. However, why couldn't the Hubble Space Telescope be used to image the non-Mariner side of Mercury? Hubble has resolved details on some of Juptier's moons (about the same size as Mercury) and Mercury is far closer to us.

[lyford]

These are great images obtained from the ground.  However, why couldn't the Hubble Space Telescope be used to image the non-Mariner side of Mercury?  Hubble has resolved details on some of Juptier's moons (about the same size as Mercury) and Mercury is far closer to us.

Mercury is too close to the sun to be safely imaged by the Hubble.
OUCH!

[djellison]

iirc - Hubble has a minimum sun angle which is can NOT go over - I dont think it's ever imaged Mercury simply because it's too close to the sun - and the damage that could be done is huge.

Doug