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Mars Polar Lander Lost Again
IZ Reloaded writes "The Mars Global Surveyor during one of its latest scans of the area where the Mars Polar Lander was originally spotted, discovers that the spacecraft is no longer there! Space.com reports, "We conclude that our interpretation of these features was in error. This is not the location of the Mars Polar Lander. Because the landing uncertainty ellipse is so much larger than our images, and we do not have another candidate to which to target...we cannot continue to hunt for the lander," the MSSS site explains."
perhaps the lander could have been covered by dust, or c02 frost -- therefore eliminating the weak detection seen before?
List of Mars Efforts, courtesy of Wikipedia
Items with bullets represent full or partial failures.
* 1960 -- Marsnik 1
* 1960 -- Marsnik 2
* 1962 -- Sputnik 29
* 1962 -- Mars 1
* 1962 -- Sputnik 31
* 1964 -- Mariner 3
1964 -- Mariner 4
* 1964 -- Zond 2
* 1965 -- Zond 3
1969 -- Mariner 6
1969 -- Mariner 7
* 1969 -- Mars 1969A
* 1969 -- Mars 1969B
* 1971 -- Mariner 8
* 1971 -- Cosmos 419
* 1971 -- Mars 2
1971 -- Mars 3
1971 -- Mariner 9
* 1973 -- Mars 4
* 1973 -- Mars 5
* 1973 -- Mars 6
* 1973 -- Mars 7
1975 -- Viking 1
1975 -- Viking 2
* 1988 -- Phobos 1
* 1988 -- Phobos 2
* 1992 -- Mars Observer
1996 -- Mars Global Surveyor
* 1996 -- Mars 96
1996 -- Mars Pathfinder
* 1998 -- Nozomi (Planet-B)
* 1998 -- Mars Climate Orbiter
* 1998 -- Mars Polar Lander
* 1998 -- Deep Space 2 (part of Mars Polar Lander spacecraft)
2001 -- Mars Odyssey
2003 -- Mars Exploration Rovers
* 2003 -- Mars Express
We have satellites orbiting Earth that can read the numbers on a license plate and they can't get a good shot of the lander? Am I missing something here?
"Is this Winkhorst a nova criminal?" "No just a technical sergeant wanted for interrogation."
We have satellites orbiting Earth that can read the numbers on a license plate and they can't get a good shot of the lander? Am I missing something here?
Maybe we don't think there's license plates on Mars?
Seriously though, what's the point of having ultra-high resolution pictures of Mars? Seeing each individual rock probbably isn't terribly usefull compared to other things the money could be used for. The CIA and NSA are obviously interested in high resolution pictures. NASA is interested in a wide range of optical frequencies, sub-surface mapping via radar, etc.
The big limitation however is just the resolution/field of view tradeoff. Usually when you're taking that high a resolution you've got a very narrow field of view. If you wanted to photograph all of Mars it'd take forever with such small swaths. Intelligence agencies don't want to take pictures of everything on the planet at high resolution, just very select things. Also, Mars is further away from the Sun so there's less light reaching Mars.
The most obvious difference of course is simply that US intelligence agencies have far larger budgets than NASA does, and obviously a smaller scope of what they're trying to accomplish.
AccountKiller
As it is, Malin's team can get sub-meter resolution on specific targets after a few passes.
"The impossible often has a certain integrity that the merely improbable lacks" - Dirk Gently
Last I heard, ~4" resolution was available during the mid-80's. More current information on available resolutions is top secret and not available to the public.
Chances are, resolutions available from modern spy sats provide better than 4" resolution...especially when you consider the improvements available in active optics (active mirrors, etc), radar, and IR technologies.
Do a search on the Rayleigh criterion as it pertains to optical telescopes. Take, for example, the 200" (5.8 m) telescope on Mount Palomar. Under optimal conditions, it has a resolution of about 0.2 arcseconds. Put it up in LEO at, say 200 miles, and that would be an equivalent of about 1.6 inches on the ground. The HST with it's 2.4 m mirror would be about 3 inches.
Unless they're doing some fancy stuff with multiple satellites, the HST's resolution is about the limit of what you can expect with optical telescopes.
- AlanH