Five New Neptunian moons

cyclop writes "It's a new time of discoveries in the Solar System. Just when Cassini discovered two news moons on Saturn, old Earth-based astronomy strikes back by revealing five small bodies around Neptune. The faint moons seem to have eccentric and inclined orbits, and to have been captured by Neptune."

Comments

Mission to Neptune

[cephyn]

Planetary scientists would LOVE a galileo/cassini type mission to neptune. The planet and its moons are just bizarre. It has normal looking full sized moons in retrograde orbit - which normally implies captured bodies...but they are usually irregularly shaped. It has goofy looking moons in normal orbits, which would normally imply a body formed with the planet...but those aren't usually irregularly shaped. And the big moon, Triton, is amazing...huge geyser/volcanic-like plumes of frozen black-stuff. There's theories as to what it is, but the underlying mechanisms aren't well understood. An amazing outer planet.

Re:Mission to Neptune

[ToshiroOC]

Prometheus and JIMO first. Prometheus and JIMO are two overarching names for two similar projects - Prometheus specifies the development of nuclear reactors for generating electricity in space for spacecraft. JIMO stands for the Jupiter Icy Moons Orbiter.

This is a huge development in interplanetary science, once they get it all designed - current technology can't begin to approach nuclear levels of power in space. The solar panels on the rovers bring in ~450watt/hr per day (up to 600 in the right orientation), but solar panels just don't give enough electricity once you start getting out away from the sun - Mars is about as far as you can practically go with solar panels. RTGs (radioactive thermal generators) provide power on the order of 1000-2000 watts for the newer ones, and notably less for the older ones - the 30+ year old Voyagers are running off of these, as is Cassini. Nuclear reactors are planned in the 100,000 watt range to begin with, scaling up to ~1,000,000 watts in the forseeable future.

Science, once Prometheus gets off the ground, is no longer going to be centered around minimizing power usage, but maximizing science return. Ion thrusters, which use very little physical fuel but massive amounts of electrical power, become significantly more feasible for very long trips.

And that leads to JIMO - Jupiter Icy Moons Orbiter. Nuclear powered, ion thrusters, all the science you could ask for. Looking at Europa and more.

The only issue is to get Congress to stop cutting 100s of millions out of the Prometheus/JIMO budget - which they did for FY2005.

AFTER all of this, once we have nuclear and ion propulsion down, we can go out to Neptune. Neptune is a much greater challenge because its much further out - you need more efficient thrusters and more power, and you also need much more powerful transmitters to get enough data back to earth.

Re:But would they have thought to look?

[Chuck1318]

If it wasn't for Casini? After all, who had imagined moons this size before?

Well, yes, Cassini had nothing to do with it. The five newly discovered moons of Neptune are larger than Mars' moons, which were known before space flight. The Galileo probe to Jupiter discovered numerous moons about the size of the ones recently found by the Cassini probe. The moons are being publicly reported now, but they were observed in 2001 to 2003, before Cassini got to Saturn.