Nasa Picks "juno" As Next New Frontiers Mission |
Nasa Picks "juno" As Next New Frontiers Mission |
Guest_BruceMoomaw_* |
Jun 1 2005, 10:10 PM
Post
#1
|
Guests |
http://www.nasa.gov/home/hqnews/2005/jun/H...rontiers_2.html
Yeah, I know it ain't Saturn, but we don't seem to have any proper slot for Jovian news -- including yesterday's totally unexpected announcement that Amalthea's density is so low as to suggest that it's a highly porous ice object; maybe a captured Kuiper Belt Object reduced to rubble by infalling meteoroids. As Jason Perry says, this might explain those previously mysterious light-colored patches on Amalthea -- they may be its underlying ice, exposed by impacts that punched through the layer of sulfur spray-painted onto it by Io. Scott Bolton has been pretty talkative to me already about the design of Juno. It certainly won't be as good in the PR department as Galileo or Cassini, but it DOES carry a camera -- as much for PR as for Jovian cloud science, according to Bolton. And since the latitude of periapsis of its highly elliptical orbit will change radically during the primary mission, I wonder if they might be able to set up at least one close photographic flyby of Io and/or Amalthea? (I believe, by the way, that this selection is a bit ahead of schedule -- and it certainly indicates that NASA's science program under Griffin won't be a complete slave to Bush's Moon-Mars initiative.) |
|
|
Guest_BruceMoomaw_* |
Jun 19 2005, 11:54 PM
Post
#2
|
Guests |
"Are you talking about the Hubble II complete new vehicle idea, rather than a repair? The arithmetic is impossible to argue with (which is presumably why the DoD do it that way for their spy satellites)."
Oh, yes (although the DoD does have another reason adequate by itself, namely that they can't launch Shuttles into polar orbit). And the design for Hubble II is already full-ripe: see http://www.pha.jhu.edu/hop/ . The Aerospace Corporation study commissioned by NASA itself to compare the the three ways to deal with the Hubble problem ( http://www.npr.org/programs/morning/featur...bble/hubble.pdf ) concluded that HOP was not only as cheap as a Shuttle repair mission, but about 20% more likely to succeed (and without risking any lives) -- and, as you'll see when you look at HOP's design, it would carry, in addition to the two new instruments planned for Hubble, at least one and maybe two radically new instruments giving it greatly expanded capabilities beyond Hubble. Two days later, the National Academy of Sciences muddied the waters by stating in its own report that a Shuttle repair mission would be better -- but their reasons for doing so are incredibly vague; indeed, they only mentioned the reflight possibility at all in one short paragraph on one page! ( http://www.nap.edu/catalog/11169.html ; pg. 39). And my attempts to extract more information from the N.A.S. on why they made that statement have been totally unsuccessful. I imagine, though, that we'll see the Shuttle repair mission instead -- after all, NASA, like any con artist finally backed into a corner, is frantically grabbing at anything they can, and the supposed "usefulness" of a Shuttle repair mission to Hubble is the only argument they have left for that miserable white elephant that still has an ability to take in otherwise knowledgeable skeptics (such as Paul Krugman). "It still leaves the vexed question of what to do with the original Hubble - unmanned rendezvous appears still to be a bit of a black art in the US (perhaps subcontracting the de-orbit to those guys with the Ariane mini space-tug would be a better idea, or even finding out how NPO-Energia would feel about selling a Progress de-orbit mission to NASA (bet they'd *love* to sort out NASA'a pride and joy after being 'persuaded' to dump their good ol' Mir in the ocean!)). Of course, you could always stick some gyros, comms and solar cells on a PIRS airlock module atop a Progress bus, boost the whole shooting match a couple of hundred miles higher and wait for Burt Rutan..." Once again: since they can't possibly cram a Deorbit Motor into the Shuttle cargo bay along with the other equipment they'd need for that repair mission, that will be separately built and robotically launched to Hubble in any case (for about $400 million). Orbital Services is absolutely confident that they can build that simpler mission, and succesfully dock it with Hubble. Of course, a few heretics like Jeffrey Bell are also asking why we need to spend $400 million to eliminate the miniscule chance that any piece of Hubble would hit anyone on the head in any case... |
|
|
Lo-Fi Version | Time is now: 26th September 2024 - 02:02 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |