Tenth planet Thread (merged)

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A new solar system object past Pluto and Neptune's object with a moon, which is smaller than Pluto has been discovered. (This is also very delicate wording. The sensational way to word it would be: "New Planet Discovered Past Pluto!", but given that Pluto just barely qualifies to be a planet, this would clearly not).

The best quote from the story (in the duh! category):

If the mass is only one-third that of Pluto, then theory holds that it can't be larger than Pluto
Details here: http://www.space.com/scienceastronomy/050729_large_object.html


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BREAKING NEWS: trans-Neptunian object discovered

"Astronomers have found a large object in the Solar System's outer reaches. It is being hailed as "a great discovery".

Details of the object are still sketchy. It never comes closer to the Sun than Neptune and spends most of its time much further out than Pluto.

It is one of the largest objects ever found in the outer Solar System and is almost certainly made of ice and rock.

It is at least 1,500km (930 miles) across and may be larger than Pluto, which is 2,274km (1,400 miles) across."

Distant object found orbiting Sun
Hmmm... a possible new planet member of our solar system(albeit small)? Nice.
Not so easy, guys... Check these links:


This is ANOTHER object! We have THREE new big objects:

2003 EL61
2003 UB313
2005 FY9

Links for more info about each object:


And 2003 UB313 is at least the size of Pluto - it could be significantly larger. Would be interesting to know, will these discoveries change the mission to Pluto?
You can see their orbits here:

http://neo.jpl.nasa.gov/orbits/2003el61.html [Broken]
http://neo.jpl.nasa.gov/orbits/2003ub313.html [Broken]
http://neo.jpl.nasa.gov/orbits/2005fy9.html [Broken]

2003EL61 is 51 AU from Sun, brightness: 17.7 mag
2003 UB313 is 97 AU from Sun, brightness: 18.9 mag
2005 FY9 is 51 AU from Sun, brightness: 17.4 mag
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Very nice job Tony!


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s3nn0c said:
You can see their orbits here:

http://neo.jpl.nasa.gov/orbits/2003el61.html [Broken]
http://neo.jpl.nasa.gov/orbits/2003ub313.html [Broken]
http://neo.jpl.nasa.gov/orbits/2005fy9.html [Broken]

2003EL61 is 51 AU from Sun, brightness: 17.7 mag
2003 UB313 is 97 AU from Sun, brightness: 18.9 mag
2005 FY9 is 51 AU from Sun, brightness: 17.4 mag
http://science.nasa.gov/headlines/y2005/29jul_planetx.htm?list45222 [Broken]

Here is a NASA press release about the one that is bigger than pluto
(IIRC it is 2003UB313)
quotes Mike Brown to the effect that even if the albedo were 100 percent it would still be as big as Pluto
that's how bright it is.
so since not perfectly reflective, must be larger
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Very incredible!, they have discovered Planet X!

http://neo.jpl.nasa.gov/orbits/2003ub313.html [Broken]
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10th Planet Discovered

Well folks, the 10th "planet" has finally been found. See
Astronomers announced that they had found a lump of rock and ice that was larger than Pluto and the farthest known object in the solar system.
If you can find more online info please let me know. Thanks.

yourdadonapogostick said:
you forgot Sedna
I didn't forget it. This is Sedna. It has been confirmed that Sedna exists. This is the confirmation. The existance of Sedna has not been confirmed before this.
i thought you were talking about the new one

edit: you need an account for the link
pmb_phy said:
I didn't forget it. This is Sedna. It has been confirmed that Sedna exists. This is the confirmation. The existance of Sedna has not been confirmed before this.
No, no, no... The existence of Sedna was confirmed long before... We are here talking about two newly discovered objects, 2003UB313 (nicknamed "Lila"), which should be considered as the 10th planet (because of its probable 2600 Km diameter), and 2003EL61 (nicknamed "Santa"), which is approximately the size of Sedna. But these last objects are not Sedna, which "code" is 2003VB12.

These 2 discoveries have created a lot of confusion in the medias because they were announced almost at the same time.
This is wonderful!

Thank you all for the nice links. :)
According to BBC some people want to name this new "planet" Xena (The warrior princess) :yuck: It sounds stupid for a plaanet...


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DeathKnight said:
It sounds stupid for a plaanet...
So does 'Earth', but we're stuck with it. :rolleyes:


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Lila I like. Santa and Xena have got to go.


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Science Advisor
Now its on wikipedia -





The downside of this news is that someone was apparently trying to publish this information and claim credit for the discovery.
Why the hasty announcement? What about the hacking? What is going on here?

As has been widely reported in the press, the announcement of the new planet was made in a rather hasty manner because of fears that our discovery was going to be made public by someone who had hacked a web site and gained access to information about where the object is. The details are a little more complicated than this, the terminology can be debated ("hacked?" "sleuthed?" "stole?" "stumbled across?") and not all are 100% clear to me, but here is a reconstruction of the events that lead to the announcement as best I can discern them. Some aspects remain mysterious.

In mid-July short abstracts of scientific talks to be given at a meeting in September became available on the web (for example, here). We intended to talk about the object now known as 2003 EL61, which we had discovered around Christmas of 2004, and the abstracts were designed to whet the appetite of the scientists who were attending the meeting. In these abstracts we call the object a name that our software automatically assigned is, K40506A (the first Kuiper belt object we discovered in data from 2004/05/06, May 6th). Using this name was a very very bad idea on our part! Unbeknownst to us, some of the telescopes that we had been using to study this object keep open logs of who has been observing, where they have been observing, and what they have been observing. A two-second Google search of "K40506A" immediately reveals these observing logs. Ouch. Bad news for us. From the moment the abstracts became public anyone on the planet with a web connection and a little curiosity about this "K40506A" object could have found out where it was. Anyone on the planet with even a modest-sized telescope could then go find the object and claim a discovery as their own.

Interestingly, this is not what we then happened. The Spanish group headed by J.-L. Ortiz legitimately discovered the object on their own in data from 2 and 3 years ago. The fact that this discovery happened days after the data were potentially available on the web is, I believe, a coincidence. At the time, however, some in the community privately expressed their concerns to me that this coincidence was too good to be true and wanted to know if there was any possible way that anyone could have found out the location of our object. I insisted it was impossible. I was wrong. I myself went to Google late on the night after the Spanish announcement, typed K40506A into Google, and let out a gasp. Even though I don't believe the Spanish group did this, I realized anyone could have found our object with very little effort. To be very clear, from the first day I have very publicly stated that the official discovery credit goes to Ortiz et al. and no one else.

By Friday morning it occurred to me that once someone knew about the web site where the information on where the telescopes we had been using had been pointing it would take only a little more effort to carefully peruse this web site to see if we had been looking at anything else moving in the sky. At this point I contacted Brian Marsden at the International Astronomical Union's Minor Planet Center (MPC) by email, told him confidentially about the two objects that we had not yet announced (now known as 2003 UB313 and 2005 FY9), expressed my concerns that someone may be able to nefariously find our data and attempt to claim credit for discovering these objects, and sought his advice. His chilling response came less than an hour later: someone had already used a web service of the MPC to use past observations of an object to predict locations for tonight. The past observations were precisely the logs from the telescope we had used! The culprit and not even bothered to change the names that we used (K31021C for 2003 UB313 and K50331A for 2005 FY9). At this point we had no choice but to hastily pull together a press conference which was held at 4pm on the last Friday in July, perhaps the single best time to announce news that you want no one to hear.

All of this came about because of the perfect confluence of three factors: we used our actual code name in publicly available abstracts (dumb on our part), we assumed that no one would piece together information from the internet and figure things out (naive on our part), someone with astronomical knowledge was willing to go to some effort to obtain our data (unethical on their part). It's true that the information was available without breaking into any sites. It's also true that sometimes I don't lock the door to my house. I hope that people don't think it's therefore OK to come in and take my stuff.

We have been greatly saddened by this experience but have learned many lessons. It seems likely, however, that determined people with no ethics will continue to find ways to cause problems in all fields.
from Mike Brown's website.

Abstract from upcoming conference -

37th DPS Meeting, 4-9 September 2005
Session 56 TNOs and Centaurs
Poster, Thursday, September 8, 2005, 6:00-7:15pm, Music Recital Room

[56.02] Keck Laser Guide Star Adaptive Optics Discovery and Characterization of a Large Kuiper Belt Object Satellite

Bouchez, M. Brown (Caltech), R. Campbell, J. Chin, M. van Dam, S. Hartman, E. Johansson, R. Lafon, D. Le Mignant, P. Stomski, D. Summers, P. Wizinowich (Keck Observatory), C. Trujillo (Gemini Observatory), D. Rabinowitz (Yale University)

We present the discovery of a satellite orbiting the newly found large Kuiper Belt Object K40506A (see Rabinowitz et al., this proceedings), observed using the W.M. Keck Observatory laser guide star adaptive optics (LGSAO) system. Using the V=17.5 minor planet as the tip-tilt reference, the Keck LGSAO system delivered images with a typical resolution of 0.06 arcseconds at 2.1 microns wavelength. Observations made during 5 commissioning nights between 26 January and 30 June 2005 allow us to derive the following orbital solution for the delta K=3.8 magnitude satellite with respect to the primary: a=49100±400 km, P=49.05±0.03 days, e=0.048±0.002. This implies a total mass of the system of 3.9±0.1 x 1021 kg, or 30.2±0.8% the mass of Pluto.

TNO = Transneptunian Object
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ohwilleke said:
Lila I like. Santa and Xena have got to go.
I heard the discoverer wanted to name it 'Heranus'. As a counterpart to Ur-anus. :rofl:

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