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 16 2005, 02:26 AM
Post
#2
|
Guests |
Fear not! We WILL see excellent images of Jupiter again in our lifetime, and in fact very soon. Not only will we have Juno's photos of Jupiter -- and the photos New Horizons will take during its Jupiter gravity-assist flyby in mid-2007 (which will take it just a short distance outside Callisto's orbit, much closer than Cassini came) -- but the Europa Orbiter will spend about 2 years in Jovian orbit setting itself up to enter an orbit almost parallel to Europa's, so that it can then brake into orbit around Europa itself with the absolute minimum of fuel required (which will still be a lot). In order to set up that orbit, it will make about half a dozen very close flybys of Ganymede and two or three of Callisto (along with a dozen of Europa itself) -- and they have always intended to take full advantage of its instrument payload during that long prelude to observe those two moons and Jupiter itself, using all the orbiter's Europa instruments (except maybe its subsurface radar sounder, whose antennas may not be deployed until it's entered Europa orbit). And it WILL have a high data-return rate.
The one part of the Jovian system that we may not see well again for a disappointingly long time is Io. However, serious consideration is being given to making one of the second-priority batch of New Frontiers missions an "Io Observer", which would enter a Jovian polar orbit to minimize its radiation dose, and then make a whole series of repeated close Io flybys to observe that world. (While the radiation environment at Io's orbit is so savage that it would knock out even the radiation-hardened Europa Orbiter in a few days if we tried to put it into orbit around Io instead, the radiation dose that a Jupiter polar orbiter would get during repeated close Io flybys is tremendously smaller -- such a craft could make fully 50 Io flybys before getting the same total radiation dose that the Europa Orbiter mission will get.) There's a good chance that we'll see this launched some time in the early 2020s. |
|
|
Lo-Fi Version | Time is now: 27th September 2024 - 12:11 AM |
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. |