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Hubble Photo of Sedna Suprises Astronomers
waynegoode writes "Soon after the announcement of the discovery of Sedna, the solar system's furthest object and planet wanna-be, the Hubble Space Telescope was pointed at it to answer some of the many questions its discovery generated. The photos were released today and are surprising for what they don't show--a moon. Astronomers were certain it had a moon because of its slow rotation. "I'm completely baffled at the absence of a moon," says Michael Brown, Sedna's discoverer. Story and photo at Universe Today, hubblesite and NASA press release."
The planet that's not a planet has a moon that's not there!
Perhaps it used to rotate fast, but got hit by some other asteroid in an opposing fashion, so now it rotates slowly ? Space is big (!) so this is unlikely, but if Sedna is not too far from the Kuiper belt, perhaps it's less unlikely than one might expect...
Simon
Physicists get Hadrons!
When will G.W. announce a manned mission to look for oil?
"Well, it took an hour to write, I thought it would take an hour to read."
It's an absence of a space station!
... Cue 'Hollow Sedna' theories. Oh, and a swarm of bad 'no moon, it's a space station' jokes.
Real Daleks don't climb stairs - they level the building.
with all of my astronomical knowledge the only thing i can come up with is aliens playing some sort of april's fools day joke. but this begs to ask "do alien's celebrate april fool's day or some other weird alien day?" maybe they don't call it april
any other interesting things that didn't happen today?
the sun rose so it can't be that....
water is still wet...
i'm baffled.
Maybe Earth, Sedna and "Sedna moon" are co-linear?
They said there was a very small chance that it's companion rock could be behind or in front of it, what kind of percantage are we talking about? You have to figure that the "Sedna moon" would spend at least 20% of it's time in front of or behind the planet (relative to Hubble). Imagine trying to see the moon from a telescope on Sedna, it wouldn't always be on either side, sometimes the Earth would hide it. Maybe they just need to take another photo when Hubble has another oppurtunity.
It would be surprising that Senda has a moon. After all, Sedna itself is comparable in size with our own moon (Sedna has less than 1700 Km in diameter, and our moon has around 3500 Km in size).
:-) I am sure that somebody searched for it.
Now I am wondering if our Moon has another moon orbiting around
Don't try to use the force. Do or do not, there is no try.
'Astronomers were surprised by what they did not see, a moon. The hubble telescope helped solve the problem when honed onto Sedna itself. The planet's oddly erratic, eliptical orbit is due to a giant mass on it's far side. Colon Powell presented the Hubble photographs today in a speech before the United Nations. The photographs detail the until now, 'unknown mass' that was altering Sedna's orbit. "It is clear from these photos" he said "that we have found the Iraqi weapons of mass destruction".
It is unclear how Saddam Hussein delivered and stockpiled the weapons on Sedna, but the blury photographic proof shows beyond a shadow of a doubt that the administration was in the Right from the beginning. NASA was unavailable for comment.
It's just had to change its name and location, due to an interstellar court action from Microsoft, which has claimed that the term "lunar" infringes on the term "Windows", given the obvious phonetic similarity.
When Sedna's lu--r object has found a new name, and shaken off Microsoft's legal team, it will reappear.
Except in Benelux.
Ceci n'est pas une signature
At a distance of over 8 billion miles, Sedna is so far away it is reduced to one picture element (pixel) in the image taken in high-resolution mode with Hubble's Advanced Camera for Surveys. This image sets an upper limit on Sedna's size of 1,000 miles in diameter.
So if the so-called planet is the size of one pixel, how do they expect to see a smaller moon?
And, yes, I'm quite aware of techniques such as extrapolations, anti-aliasing etc. which *may* help extract a smaller-than-1-pixel object using a series of 35 pictures, but I'd speculate that NASA's assertion that Sedna does not have a moon is premature.
Those who can, do. Those who can't, consult.
The slow rotation maybe due to the material the planet is made out of...haven't done enough research...but the limited work i've done on planetary rotation and gravity tells me two things.
The slow rotation may account for a moon or child body which was able to escape the rotational cycle, or was flung off into space during its creation. Which is FAR FAR more likely given its distance from the sun
The other reason maybe attributed to the fact that it is beyond the astroid belt, and is the furthest satellite we've discovered yet. Although it is a small target, it maybe the solar system's first line of defense (eg a riot shield) although not a good one. That could account for both slow/erratic rotation or a missing orbital body.
Kill All Humans Day
the pictures are taken using filters, not normal light, high intensity x-ray, microwave, IR...the whole deal....they are also taken in sequence, to produce multiple images of the object for sub pixel extrapolation....as a possibility described in an above post. They may have "missed it" in this round of pictures but it is highly unlikely...their guesses may have not accounted for some other gravitational body.
Story also here
Small info:
* Sedna is about three-fourths the size of Pluto.
* It takes 10,000 years to orbit the Sun.
* Sedna spins on its axis once every 20 Earth-days.
At a distance of over 8 billion miles, Sedna is so far away it is reduced to one picture element (pixel) in the image taken in high-resolution mode with Hubble's Advanced Camera for Surveys.
This surprised me a lot. Hubble can take pretty (for me as a non-astronomer) pictures of objects far away and in the past (wasn't only recently something so old that it is almost the beginning of the universe?), and yet it can't take a picture of something within our system larger than a pixel... Anyone with some knowledge care to elaborate on that?
the most sexp i get is my paren-mode.
I really pity the people on Sedna. Without a moon, how can they ever hope to get to Mars?
Check the fine print. Those images are renderings.
Sleep is for the weak.
Myabe because the distant nebulaes and stuff are actually billions times trillions times gazillions times larger than sedna...?
it's the moon!
(the planet is hiding behind it)....
______________________________________________
sigamajig...
If that's a planet start calling it Rupert, please...
We really need to replace Hubble with a telescope that won't challenge us so much.
we went to war and WON
You know, in the past, most people have waited until the other guys stopped killing them before claiming a victory.
Maybe someone should go out there and tell all those Iraqi irregulars that you guys have WON, and so could they please stop blowing shit up?
evil math within Nature's Cubic Creation!
Here you go. Asteroid Ida and it's little moon "Dactyl".
Dactyl is about 0.75 x 0.8 x 1.0 miles in size. Imagine that!! Imagine sitting on Dactyl and orbiting Ida. Now, I'm not sure if a rock of 1 mile in diameter can even hold you down.
Does anyone know how to calculate your weight on Dactyl? Size listed above and it's probably 2.2 - 2.9 grams per cubic centimeter.
... the future of that project. The absence of a natural moon which could have been modified a will certainly put a huge dent in G.W's budget since it forces him build from scratch the fortress-moon/deathstar needed to defend US intrests in the region. Then there is the matter of the pesky natives ....
Only to idiots, are orders laws.
-- Henning von Tresckow
I may not be a lawyer ;-) but I have just finished a Ph.D. in astonomy and I've worked with Hubble images (included ACS images) before.
NaSa are wonderful at using Hubble to produce pretty publicity images. I'm not saying that the images of nebulae etc. are not without scientific justification, only that NaSa are very good at presenting them to the public.
These images are more typical of the data taken by Hubble on a day-to-day basis; single filter images (presented in black and white) of faint objects pushing down close to the detection limit of the instruments.
We can think of 4 possibilities for why we do not see a moon around Sedna.
BTW, his site has more information on Sedna.
Sedna is.. or was classified as, anyway, a Kuyper Belt Object (KBO) so it does not follow the naming system used for other objects. KBO objects are named after gods and goddesses of creations..
Oh, and Inuits would be offended if you call them Red Indian. Any native Americans would, in fact, but Inuits are not even 'red'.
Michel
Fedora Project Contribut
Brilliant! You figured it out when all others could not. It's so simple in retorspect: Superman ran backwards around Sedna, causing it to both go back in time and slow down it's rotation!
stuff
The moon is a superdense glob, set in a special orbit around Sedna, specifically to attract our attention. We have to alter its orbit in order to indicate that we are ready to be inducted into the Federation of Sentient Planets.
This clearly, totally demonstrates why we no longer need the Hubble! With our advanced Earthbound technology, we can resolve Sedna and its moons without the assistance of an orbital observation platform and....
oh wait.
Never mind.
See more Sedna
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When plants are completely extracted of all their dark matter...
Has someone saved the animals yet? Nibbler?
www.slightlycrewed.com - Because aren't we all?
The inner system never sleeps. The outer system never wakes.
Sounds deep, but unfortunately, it is incorrect. Mercury (it doesn't get more "inner" than that) "sleeps" a great deal. Due to its eccentric orbit and bizzarrely-coordinated orbital period and rotational period, a single day on Mercury lasts as long as two of its years! That is to say, its rotational period is exactly two-thirds of its orbital period, meaning "nighttime" on Mercury lasts several Earth months. That's a lot of "sleeping" for a planet in the inner system which, according to you, never sleeps.
Incidentally, while we generally presume Mercury to be a very hot place (and it is, during the day), the temperature on side of the planet that is in nighttime can drop to -150 degrees Celcius.
Like woodworking? Build your own picture frames.
Dyou guys think Richard Hoagland will manage to find some alien artifacts in those big pixels?
Are astrologers calling Sedna a "planet" or an "asteroid" - ? Since the 50's they've been waiting to ease the burden on Mercury and Venus, who currently have to rule two signs at once (Mercury rules Gemini and Virgo, Venus rules Taurus and Libra.) I've been reading an astrological course book from 1952, and they were absolutely convinced, since they'd just found Pluto, that there would be at least 2 more planets behind it, one to rule Gemini and one to rule Taurus. (Personally, I think new planets should take over for Virgo and Libra, but that's my modern opinion.)
Offtopic? Only if you've never read a horoscope.
The House Between - Original Sci-Fi Series
I want to say how refreshing it is in this day and age that a man can admit that he possibly made a mistake, or that even better, he doesn't really know. Taking some responsibility is nice to see nowadays. I know this scientist doesn't hold a publicly elected position, so he can say things off the cuff. I've probably just been watching too much c-span lately.
Th
Any enlightened thinkers care to explain?
[Fuck Beta]
o0t!
"Hubble Photo of Sedan Suprises Astronomers"
I immediately pictured astronomers scratching their heads over Hubble photos of my former '86 Oldsmobile Cutlass Supreme, named "Plum" (for the color, and short for "Plum Tuckered Out")... zooming through the far reaches of space.
So it DID go to car heaven!!
There are only 10 types of people: those who understand decimal, those who don't, and, uh, 8 other types I forget.
Hephastus hasn't been used (I don't think)
You've obviously never heard of the planet Vulcan... duh.
I guess you have no sense of scale. You see, a galaxy is very, very, very, very big, and Sedna is only sorta big. . . .
Don't allow Hubble to fall back to Earth. It is still doing good science and can for years to come. New modules for Hubble have already been built and tested and only await a shutle mission to be installed. Call your congressman / woman today. Here is some info from the Mars Society on the work to save Hubble.
JET Program: see Japan, meet intere
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The space station and hubble are within the ionosphere.
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Sedna is 90% of the way to the heliopause, which is the edge of the solar system.
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Sedna is farther from us than any man-made device, including Pioneer 10 and both Voyagers.
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The Oort cloud covers an entire order of magnitude, and then some. That means the far edge is over 10 times further than the near edge. Its volume absolutely dwarfs the solar system.
Fascinating stuff.Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
The electronic detectors (CCDs) on HST, as on virtually all professional telescopes, are inherently monochrome detectors. During an exposure, the detector is behind one of several filters. There are filters that pass UV light, blue light, green light, red light, infrared light, etc. In many cases, the same bit of sky is observed in multiple filters, one after the other. If these happen to be red, green, and blue filters, you can put the three images in the red, green, and blue channels of a color image, and get something that's approximately true color. The filters are not designed to exactly mimic the human eye's color response; that's not an important concern from a scientific standpoint. If some other combination of three filters is used, they can still be placed in the RGB channels of an image, but the result will be a false-color image. That doesn't mean the color information is meaningless; parts of the nebula that look "blue" in the image probably have something physically different happening than parts that look "red."
Many people have an unrealistic expectation that colors in astronomical images should be exactly correct. That's a hard thing to nail down. As I mentioned above, the filters are not designed for human-vision color fidelity, since that's not relevant to the scientific goals at hand. Also, if you look at a nebula with your eye, even through a very large telescope, you vision will be dominated by the color-insensitive rods, and the nebula will appear quite washed-out. So do you want the publicity pictures to mimic this shortcoming of human vision (that we don't see much color in faint things)?
Back to the topic of the CCDs being monochrome detectors: This is true of the CCD or CMOS detectors in consumer digital cameras, too. But instead of putting the whole detector behind a colored filter, each pixel on the detector is behind a tiny red, green, or blue filter. Thus, each detector pixel is still only recording one of the three colors of light. (The new Foveon chips are an exception to this rule.)
Escape velocity would have been more informative, which using your values of r and rho comes out to .9 m/s or about 3.2 km/hr. Just trying to walk would cause you to fly off the surface, though I guess you'd still be stuck orbiting Ida.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
It's a gas station.
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Because Soviet Russia was a bigger threat than any third world country was. The US through it served their interests in containing the spread of communism to arm Iraq against Iran.
That's a new one. The way I always heard it was that Iraq was fighting a war against Iran, who was our enemy. And how do you think the Iraqis got MiG jets and Russian tanks? The russians didn't like the Iranians either! It wasn't the Russians we were trying to fight, it was the Iranians.
Becuase it was an election year, and he didn't want to have to deal with the bloodshed that is going on now back then. He would have been re-elected too, if it hadn't been for Perot.
Yes!!! Finally one of you admits that Bush is going down in November!
I don't see it that way, wars are usually struggles over resources. While left leaning people are saying Iraq is over oil, and the righties are claiming its about the freedom of the Iraqi people it's really about striking fear into leaders of other muslim states.
If it's about resources, then planning and equal distribution would prevent war. If it's about religion, it's a little harder, but appearing non-threatening and friendly is a great way to keep religions from not liking you. Maybe it's about fear, but if we have to make people afraid of us in order to be secure, we have big issues. Why not try to make people like us instead of being feared?
Yeah it sucks, but until resources are unlimited and all men and women are equal in every way, there will be violence. Religion also seems to be a driving factor twards war historically. Maybe one day we will get over the violence of ancestors, but I doubt it. I hoped after the cold war the world would see a few hundred years of peace, but no dice. Maybe someday.
No, when people see that violence is wrong, and when it is not tolerated by all societies, then war will end. People who claim that war is necessary provide justification. War is not necessary. The more people who think this, the less war will be an option, and the more peaceful the world will become.
As for resources: Greed causes shortage, and greed is rewarded under capitalism, therefore capitalism, just like Marx said, causes war.
I'm in the hole of the broadband donut.