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The Tenth Planet Shrinks Under Hubble's Gaze
starexplorer2001 writes "An object called the 10th planet by some astronomers is not as large as previously thought. New images of 2003 UB313 (aka Xena) were delivered by the Hubble Telescope and showed up as only 1.5 pixels! Now, some are calling to demote Pluto and kill Xena."
Maybe it's all black except for a bright white spot.
Forget Xena, the planet should be named Marvin.
Mea navis aericumbens anguillis abundat
New Face discovered on Mars
A pixel is small, but nowhere near subatomic. It's measured only in microns.
When photons are distributed over the CCD surfrace, it has some measureable shape (e.g., Gaussian) which can be fitted as such to characterize the shape. The quoted size of 1.5 pixel is, I think, the FWHM of the fitted Gaussian function that characterize its source.
Ah, I still remember fondly the first time I saw a slashdot thread climb to a few hundred posts of argument about 'what makes a planet a planet?'. If ever a term was crying out for a rigid, ostensive definition from astronomers, it's 'planet'. From the ancient greek word for "wanderer", if we don't tighten it up some, the argument will come trotting out every time someone finds a rock doing laps about the sun. Stays within 10 degrees of the ecliptic, say 3,000km across...that works for me.
"New images of 2003 UB313 (aka Xena) were delivered by the Hubble Telescope and showed up as only 1.5 pixels! "
1.5 pixels on what scale? A pixel is not a unit of measurement for size, it just denotes the smallest distinct unit in a picture. Yes, it appears sensational to say that a 'planet' appeared to be 1.5 pixels (100 exclamation marks), but that's just as stupid as saying that my backyard appears to be 5 pixels wide on Google Earth. Gives no information unless you say that the resolution is 1 pixel = X metres.
"When the only tool you own is a hammer, every problem begins to resemble a nail." - Abraham Maslow (1908-1970)
...post a link to the image?
Visit http://ringbreak.dnd.utwente.nl/~mrjb/growingbettersoftware to download your free copy of the book
A pixel is small, but nowhere near subatomic. It's measured only in microns
By atomic, the author means it cannot be divided further. This was the original meaning of atom. Atomic is a word used in computer science to indicate an operation that can't be interrupted. It either happens completely, or doesn't happen at all.
AccountKiller
As George Carlin said pollution; Earth will be fine. We might be fucked; but the earth will be A-OK.
It's because the word planet isn't really a scientific word. There's no hard point where something becomes a planet and where it's not a planet. Words like planet are really just our own convienent language definitions. Arguing about whether something is a planet or not is a little like arguing whether something is a chair or not. It only matters based upon useage.
AccountKiller
It can be derived with trigonometry:
(angle)*distance_to_the_object == size_of_the_planet
which are
(1.5pixel*0.025"/pixel)/(60*60*57.3radian/") * 100AU * 1.5e8 km/AU ~ 2700km.
If you read the article, you'll find that the size is only 1400km, though.
The difference results from the fact that the measured size of 1.5 pixel
includes the size of its point spread function for the HST/ACS/HRC (i.e.,
even a true point source show some finite size in optics...something we
cannot beat).
I don't understand why this is so hard to understand. The only sensible definition for a planet is an object that is spherical due to its own gravity, orbits a star, and is not itself a star. But these bozos keep saying "But Pluto is so different from the other planets, we can't call it a planet!" Well boohoo. So it's freaking different! Earth and Jupiter are somewhat freaking different from each other, last time I checked, but we call both of those objects planets! "But then there will probably be a thousand planets in the solar system!" they say. I say, get over it! This is not a big problem unless you're an astrologer! I honestly don't give a rat's ass about Pluto's legacy as being called a planet, if we are going to continue calling it a planet then we also need to call this other object (and several others) planets as well. The problem is, we keep being told that this needs to be controversial because defining a planet is somehow difficult, what I think is happening here is that there are a group of scientists who have an emotional problem with there being a thousand planets in the solar system and are preventing the IAU from adopting the obvious definition.
"Remember, there never were pineapple-almond cookies here."
NASA secretly discovers disturbing facts about the nature of the tenth planet, and decides the news is too shocking for the wide audience. A plan is created to announce the news in several manageable bites:
:)
1. tenth planet not as big as previously thougth, it's more like a small planet, but hey it's a still a friggin 10-th planet, right!
2. tenth planet not a planet as previously thougth, it's more like a moon of Pluto.. but it's still a friggin planet, if not THE 10-th planet...
3. new moon not really a moon, turns out it's more like a really big meteor, so big, it's kinda as big as a moon, almost, but not exactly...
4. big meteor kinda smaller than big, more like, medium meteor, still there though! xena, the medium meteor!! Yei!
5. ok maybe it's not that of a medium, more like a small meteor, little warrior meteor thingy.
6. hey what did you know! that little meteor thingy noone really friggin cares about, was a smudge on the Hubble lens system! huh, sh*t happens, but it's not like we confused it to be the 10-th planet in the Solar system, I mean, cut us some slack, come on
7. hey watch us drink cola in zero gravity. wobble, wobble, wobble, wobble!! lol!
Well, what kind of a name should that be anyway? Xena is not a roman god or goddess, not even a small one like Luna, Nike or Pluto.
So if this object should be called a planet, here's the proper list of names to choose from:
Acca Larentia, Alemonia, Anna Perenna, Carmenta, Carna, Consus, Dea Dia, Feronia, Flora, Fons, Furrina, Maia, Nike, Ops, Pales, Pomona, Portunus, Robigus, Silvanus, Veiovis, Vertumnus, Volturnus
everything else is not acceptable.
"The more prohibitions there are, The poorer the people will be" -- Lao Tse
Don't forget it's a reversed (negative) image, so Xena itself is dark and the background of space is white.
I think if you look very closely you can see a few faint stars in the background...
" "...kill Xena"
...
I thought network television did that..."
You are wrong, she came back as a Cylon
You guys are making this too complicated. NASA's site says: "Located 10 billion miles away, but with a diameter that is a little more than half the width of the United States, Xena is only 1.5 picture elements across in Hubble's Advanced Camera for Surveys' view."
Think projection in a 3D game. A pixel represents, at a projected distance of 10 billion miles, a width x. Xena is 1.5x.
The final image (as you all have pointed out) would require a minimum of two pixels of information to accurately reproduce the projected image from a distance of 10 billion miles. The second pixel would not have the intensity of the first. But from the image on the site, it looks like a lot more than two pixels of information were recorded; I don't see how they could magnify two pixels and get that.
All the Pixels around it were black except for one that was white, and one next to it that was grey, 1/2 white, 1/2 black. The pixel averages everything in the space it covers. I don't know if they actually use black or white or not, but that's how it works. Does that simplify things?
Someone save me from this sanity.
I bet they're looking at it through the wrong end of the telescope. If they turn Hubble around, that thing'll turn out to be HUGE!
"I've got more toys than Teruhisa Kitahara."
The reasons are simple. Even Mike Brown says there is no scientific basis for calling 2003 UB313 a planet. Here is what he said last year:
I will not argue that it is a scientific planet, because there is no good scientific definition which fits our solar system and our culture, and I have decided to let culture win this one.
He's using Mike Brown's acceptance of the generally accepted cultural view that planets are 'anything pluto sized or larger' as a way of discrediting 2003 UB313. In fact, Mike Brown had felt previously that the definition of Planet was unsatisfactory and threw out some ideas on how the definition could be altered. http://www.gps.caltech.edu/~mbrown/sedna/index.htm l#planets links to the text in question. Mike Brown has since come to the conclusion that culture is going to decide what defines a planet, not a bunch of scientists. So basicly, unless the scientists who want to change the definition of a planet can convince society to listen, it's going to be like a tree falling in a forest with no one around to hear it. Sure, it happened, but who cares?
"The bass, the rock, the mic, the treble. I like my coffee black, just like my metal" - Mindless Self Indulgence
According to the TV show CSI, they can take that pixel increase the image size and then enhance it enough to make out all the different geographical terrian on the planet/object in space. I tried it in Photoshop and it just doesn't work.
Can I bum a sig?