Nasa Picks "juno" As Next New Frontiers Mission Options

[Guest_BruceMoomaw_*]

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_*]

Yup -- they've had solar panels planned for a Jupiter Polar Orbiter from the very start, a decade or more ago. They also intend them for the Jupiter Multiprobe Flyby mission, whenever that flies -- and one study for NASA's 2001 Outer Planets Exploration Workshop concluded that they were also entirely practical for a SATURN Multiprobe Flyby mission: http://www.lpi.usra.edu/meetings/outerplan...01/pdf/4113.pdf

The reasons are simple:

(1) Much lower cost.

(2) No safety concerns.

(3) They're not so heavy that you can't easily make them big enough for a Jupiter mission to have a data-return rate of several hundred bps or more -- which is all Juno or those other missions require.

(4) The orbits planned for these missions involve much lower radiation exposure -- one of the major vulnerabilities of solar cells -- than a Jupiter orbiter in the equatorial plane.