Sedna May Have A Moon

ArrayIndexOutOfBound writes "The newly found planet Sedna may have a moon. It appears that most astronomers argue that Sedna is only another proof that neither Sedna nor Pluto are really planets. Interestingly, the planet has been found by an 'automated sky survey telescope'..." SYSS Mouse points to a NASA page with more information about "our potential 10th planet. ... It is 130 billion miles away from the sun (900 times Earth's distance from the sun) and has a 10,500 years orbit, compared to Pluto's 230 years around the sun."

Comments

Re:Sedna has a moon...

[linzeal]

Websters is hardly scientific canon esp. since some asteroids have moons.

Mission to Sedna

[adeyadey]

I understand that the "pluto - new horizons" mission, due hopefully for launch in 2006 (http://pluto.jhuapl.edu/mission.htm) is looking for possible KB targets after getting to Pluto in 2015. I wonder if the planetary line-up would allow one of those targets to be Sedna? (prob not, but you could be lucky..)

Is there a chart anywhere that gives the location of all these various objects in relation to the solar system, at any given time?

There is another deep-space mission in the pipeline (ion-drive) to the heliopause and beyond - is Sedna positioned toward the heliopause?

By the way, Sedna is another good reason to upgrade and keep Hubble going..

Re:Mission to Sedna

[adeyadey]

You may be right, but then again, they probably didnt think that Voyager 2 would still be around and in use today when they launched it in 1977.. But yes Sedna is a long way out, and if the line up with Pluto isnt right, forget it..

Re:Planet X

[RobertB-DC]

Ya ya, I'm being silly.

You're being silly, but the tin-foil hat crowd is going to have a field day with this baby. Consider the links that they'll find to their planet-killing Nemesis object:

* Highly eccentric orbit with a period ~10k years. They'll make up a mass extinction event to match the planetoid's period, you watch.

* According to this article, Sedna is the reddest object found in the solar system except for Mars. Watch the Nemesisians find deep significance in this fact -- we could start a pool to guess when they start calling it "blood red".

* In the "just enough facts to be dangerous" department, they'll point out that its size can't be determined directly -- that it depends on assumptions about the planet's albedo. If it's darker than expected, then it'll be bigger than expected. Ergo, the scientists are conspiring (as usual) to make it smaller than Pluto. Their "scientific" conclusion: it's the brown dwarf companion to Sol that they've been predicting all along.

Interestingly (to me at least), I submitted this story as soon as I saw it... and it was rejected almost as quickly. I suspect the editors were looking for a submission without tinfoil hat references -- a laudable goal. But even if we Slashdotters are gathered to discuss the real science, our less-informed Internet brethren haven't had much to talk about since the Martians quit shooting down spacecraft...

Intermingling of fact and definition

[dpbsmith]

It is always interesting to watch science being created. In this case, you see the nexus of a) actual facts (the discovery of a celestial object) with b) the completely artificial process of trying to name and classify things.

Is Sedna "really" a planet? Sedna is what it is, of the size and composition that it is, in the orbit that it is in. Sedna does not know or care whether it is "really" a planet or a minor planet or a dwarf planet or a comet.

Naming disputes are interesting because they always reflect the relative influence and authority of the people giving the names. Not being an astronomer, I can't identify who exactly is jockeying for positioning. Naming and classifying are part of the prescientific process. In a few decades we will probably have a better idea of how real these groupings of similar objects really are.

Re:Intermingling of fact and definition

[CheshireCatCO]

I am an astronomer and as far as I know, none of us is trying to get this beast classified as a (major) planet. It's most likely (by anyone's definition) an Inner Oort Cloud object. That more than adequately describes it in relation to the rest of the solar system. The whole idea of there being a controversy is more of a media/NASA press-office construction than a reality.

And while on one level you're right, names are artifical, on another you miss the point of naming entirely. What we call things affect how we consider and perceive those things. Language shapes our thoughts, after all. So classification isn't "prescience" it's a part of the scientific process. Classifying living organisms was the first step towards understanding their relation and then their evolution. Classifying celestial objects plays the same role. It may not be as scientific sounding as producing numbers and plots, but it's important none the less.

Re:Sedna has a moon...

[p4ul13]

Ok, I'm with you up to the solar system being called Stanley. Are you joking or is that real?

All true up until the Stanley part. Our solar system is the Sol system, though there might be another more specific name for it that I'm not aware of. I suppose "Home" is good enough.

Re:Value out of bounds

[wideBlueSkies]

>>Dr Michael Brown, an astronomer at the California Institute of Technology in Pasadena, who led the NASA-funded research, said: "The sun appears so small from that distance that you could completely block it out with the head of a pin."

Doesn't seem to make sense to me. I can't block out any of the stars in Orion with a pinhead, and they seem to me to be much further away from Earth than Sedna is from Sol.

Funny that Dr. Brown is talking about pinheads....

wbs.