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."

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:Mission to Neptune

[Christopher Thomas]

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.

Alternatively, you can just use a bigger radio dish to receive the signals on Earth. The Voyager and Pioneer craft use RTEGs, but can still be heard as long as we're willing to spend the money to listen. It's only becom

Re:Mission to Neptune

[ToshiroOC]

Bigger radio dishes are in the works, but those aren't built yet - another concern for a later day. As it is, DSN (deep space network) recieve/transmit time on 70m dishes is massively expensive, and making these missions cost efficient is a big deal - so I see this as one of the major areas in which there could be improvement before outer solar missions.

The reactors they are talking about actually aren't PBRs, I believe, but complex rod arrangements that allow reactors to be as inert as several hundred po

Re:Mission to Neptune

[Dark Lord Seth]

There are rumors out there of a planet that consists for 70% out of water. It's crust is broken up, creating a geologically interesting system. Due to a high-density atmosphere, it has severe variations in temperature... The farther away from the equater, the colder it becomes. However, the same atmosphere retains heat and causes the dark side of the planet to remain nearly the same temperature. The largest bodies of water on the planet are alive, with massive slow moving currents miles underneath the surface and magnetic activity in the atmosphere causese electrical discharges more powerful then mankind has ever been able to create. The core of this planet is made up out of molten metals and projects a gigantic magnetic field around the planet... Etcetera.

Of course, I'm talking about Terra. Sol 3. Our Earth. Just a friendly reminder that practically ANY planet is, in it's own way, amazing. :)

Re:Mission to Neptune

[R.Caley]

There are rumors out there of a planet that consists for 70% out of water.[...] Of course, I'm talking about Terra. Sol 3. Our Earth.

In a quick calculation from some numbers to hand I make it more like 0.0003%.

Due to a high-density atmosphere, it has severe variations in temperature...

Isn't the variation in temperatiure mostly due to difference in orientation to the sun.

Re:Mission to Neptune

[mcmonkey]

Due to a high-density atmosphere, it has severe variations in temperature...

Actually, due to the amount of liquid water on the surface, Sol3 has very slight variations in temperature. Prevailing currents carry heat from the equatorial regions to the poles.

Retention of heat by large bodies of water and the 'high-density atmosphere also severely reduce the variation in daytime and nighttime surface temperatures. In contrast, temperatures on Mars, with its this atmosphere, vary from about 27 C daytime to

Re:Mission to Neptune

[cephyn]

I agree that all the planets are uniquely fantastic. But many people think "Neptune? bah. just another gas giant. ho hum" -- or they think all moons are like our moon -- pretty much just a boring rock.

Re:Mission to Neptune

[adeyadey]

There was an interesting article on spacedaily.com (The case against Hubble) [spacedaily.com]
which, although primarily about Hubble, mentioned the fact that NASA rejected a much cheaper mission option for a Europa-only orbiter costing around $1 billion in favour of the $8 billion JIMO mission. You could have 10 or more SEP/RTG missions for the cost of JIMO.. Solar can even be used for getting to Jupiter-Neptune, by swinging in close to the sun first & picking up momentum with SEP or a solar sail.. Just carry enough

From an astronomer

[Pi_0's don't shower]

Ground based astronomy isn't as sexy as space based astronomy, but has one big advantage -- light gathering power. We can build 8-meter (SUBARU and GEMINI), 10-meter (KECK), and in the near future 30 to 50-meter [noao.edu] telescopes. The JWST [nasa.gov], by comparison, is only 6.5 meters, and that's still 7 years away (at least). It's expensive to get telescopes into orbit, first off, and to send a probe up, well, you only get one look at the system with that! Additionally, launching anything drives the cost up by tens of millions of dollars. Ground based telescopes are easier to service, last virtually forever, and only have the disadvantage of having the atmosphere to fight with. Adaptive optics [ucolick.org], and camera technology have significantly advanced in recent years, so that ground based telescopes with adaptive optics have huge advantages over those without it. They haven't caught the space telescopes yet, but the gap is closing. I'm a huge advocate of hubble, chandra and other space-based missions, but what can be accomplished on the ground (such as this) [njit.edu] should NOT be overlooked!

Re:From an astronomer

[cephyn]

regardless, even smaller space telescopes can still do some things better than ground based. I'm all for advancing and utilizing BOTH techniques as much as possible. More science == good. 8D

Re:From an astronomer

[Ragnarok21]

Instead of placing telescopes in orbit, we should be putting them on the moon. Low gravity and no atmosphere are a huge plus for building large aperture instruments.

Re:From an astronomer

[Chuck1318]

Instead of placing telescopes in orbit, we should be putting them on the moon. Low gravity and no atmosphere are a huge plus for building large aperture instruments.

At present, any instruments are manufactured on earth, and it takes a lot more to put anything on the moon than in orbit. So anything we could put on the moon would be a lot smaller and less capable than what we could put in orbit. Maybe someday if we had a moon base and actual manufacturing capability on the moon it could be possible. Arthu

Re:From an astronomer

[ToshiroOC]

Inflatable optics are a huge new field opening up - the idea is you either send up an optical-quality film that you can stretch out into a nice, HUGE, easily-altered-for-adaptive-optics mirror, or alternatively construct one in space (so you don't have to ruggedize it for the high-G-force ride into orbit). Look at BAA03-24 [eps.gov]for a quick glance at what the most recent round of funding was aimed at.

Re:From an astronomer

[R.Caley]

Instead of placing telescopes in orbit, we should be putting them on the moon.

Where they can be even harder to service and be at the bottom of a gravity well to make sure lots of micrometeorites get sucked towards them?

Low gravity and no atmosphere are a huge plus for building large aperture instruments.

Isn't that a pretty good description of a location in orbit?

Re:Is it worth it?

[cephyn]

well thats a valid argument, but it has a flaw. the money spent on science is unlikely, if pulled, to feed and clothe the poor. its more likely to be funneled into defense projects.

the other problem with the "money better spent" on feeding the hungry and clothing the poor argument is that its simply impossible to practically do that. there are too many hands the money and food must cross, and corruption is a given. Sure, we must try, but not at the expense of that which furthers other industries. And science isn't the biggest waste of money. What about the millions paid to sports stars? that should be given to the poor. How about the millions you spend on entertainment? surely you could sacrafice a little fun for someone to eat. maybe you should sacrafice all your fun. work hard and only keep what you need to live. not live comfortably, or happily, just live -- donate the rest to the unfortunate. It's a slippery slope. Sadly, feeding and clothing the poor is simply not an easy problem to fix -- diverting funds from science research is surely not the answer.

Re:Is it worth it?

[cyclop]

I just hate that kind of reasoning.

Money spent on science is not wasted. And the less practical is the science, the more I'm sure that money is not wasted.

I work in science (molecular biology), and I don't do it to help people (although I love if my research can help,of course). I do it primarily because I want to understand the Universe. I do it primarily because I think one of the most important, amazing and noble things humankind can do is trying to understand the universe we have the luck to live within. It is at least as noble as helping the poorest. If not noblest, because we will all die (poor or not poor). But knowledge will last.

Re:Is it worth it?

[shobadobs]

So what exactly do you do to help the world's hungry?

Re:Is it worth it?

[Marxist Hacker 42]

Do you really think that the rich would allow money not spent on science to go to the poor? There's a real and profitable reason to keep people poor- and a real and profitable reason to gather money up into incredibly large bank accounts under a single person instead of sharing with everybody. Note, I didn't say they were good reasons- but as long as those reasons are allowed to exist, there is NO chance of money being saved from ending projects like this going to the poor. None at all.

Re:Is it worth it?

[Anonymous Coward]

But I really see research into moons as being a waste of money that could have been better spent feeding and clothing the poorest in the world.

Fortunately, we're talking about results from an American satellite and telescopes in Hawai'i and Chile. Since your country contributed nothing to any of this, you can rest easy and stand proud.

Re:Is it worth it?

[fitten]

A lot of the money/food that already is earmarked to feed and clothe the poorest in the world never finds its way to them. In many cases, warlords in places such as Africa take the food/supplies for their own needs before it can be distributed to the needy.

Re:Is it worth it?

[DLR]

Research always pays off. Always. Sometimes it just adds to the amazing amount of negative knowledged we have (i.e. well THAT doesn't work...) but more often than not even failed experiments pay big dividends (both financialy and scientifically) in the long run. Did you know that nylon was a failed experiment? It was poured down the drain 3 times before someone realized what they had. The adhesive on the back of Post-It notes is another failed experiment (i.e. an adhesive that didn't stick permenently)

Re:Is it worth it?

[Madcapjack]

But I really see research into moons as being a waste of money that could have been better spent feeding and clothing the poorest in the world.

A worthy sentiment, but incorrect. If, for example, we diverted all funds for NASA and gave that money to the poor of America, their incomes would only be raised by a few hundreds of dollars (i'm giving a guess). Rather than take money away from worthy research, it would be better if all of the super-rich gave all of their surpluss wealth away, and the same with the

Re:Is it worth it?

[Anonymous Coward]

But I really see research into moons as being a waste of money that could have been better spent feeding and clothing the poorest in the world.

So we'll take the $5 billion dollars we spend annually on space exploration (most likely, a gross over-estimation) and distribution it evenly amongst the one billion people in the world who live in poverty and hunger (most likely, a gross under-estimation). So every poor person in the world gets an annual $5 gift courtesy of the US government.

Whoa. Huge dent in th

Re:Is it worth it?

[xigxag]

Money is not the solution to feeding starving peoples. They don't need money, they need food. And there's already more than enough of that to go around. The reason why they don't have that food has very little to do with them not being able to afford it, and very much to do with their own leaders deciding that guns and palaces are a greater priority than food, roads, supplies. Look at China. It went from having some of the worst famines in history to being a net food exporter [openhere.com] in just one generation. H

But would they have thought to look?

[Marxist Hacker 42]

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

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, [bbc.co.uk] before Cassini got to Saturn.

Solarquest

[TheSnakeMan]

Dammit, now Solarquest is even more out of date!

Orbiter Game

[vlm]

When will someone add those moons to orbiter?

Orbiter's home page [ucl.ac.uk]

Where are the Enternainment Moons?

[Bitsy Boffin]

Cassini discovered two news moons on Saturn,

Ah man, we get enough of news already here on Earth, it's all the same wherever you go, it's about time Cassini discovered some Enternainment Moons, that's what I'm talkin' about.