"Xena" now Eris

[mikeemmert]

Another thing I would like to know is, when will Eris pass in front of a star? Occultation will give a good diameter and if we're lucky, we can get Dysnomia, too! There are a couple of asteroids whose shape has been very exactly characterized this way.<br /><br />I don't expect an atmosphere around Eris, but, you never know. If somebody gave me strong odds, say, 10 - 1 or so, I would bet there was an atmosphere around 2003 EL61.<br /><br />My reasoning here is that Santa (provisional name) is covered, not with methane, but with crystalline water ice. Water ice should gradually lose it's crystalline structure under relentless ultraviolet radiation. So the crystalline structure implies the surface is new. How can this be?<br /><br />The best conjecture I can make is that 2003 EL61 has an elongated ellipsoidal shape about twice as long as it is wide. It spins very rapidly, every 3.9 hours, and has two moons. The moons are fairly large, 170 km and 350 km in diameter, and their orbits are fairly close to each other. It's possible that the moons get a tidal beating; thus perhaps their cores are heated. Which might lead to Enceladus-style geysers on the moons.<br /><br />If either Eris or Santa have moons with geysers, this should slightly reduce starlight as they pass in front of a star.<br /><br />That would be intriguing if it happens to be the case. If it does, then it would bolster the case for sending a probe to Saturn rather than Jupiter, for newbies here I have had a couple of freindly debates with 3488 over this ( a true gentleman who does not use logical fallacies or misleading arguments - and never appears in Free Space). <br /><br />Below is a picture of the Eris system, which is posted elsewhere on this thread. I have "enhanced" it, but frankly I don't know what I'm doing, I just played with contrast and brightness and color. What is that object at about the ten o'clock position? Star? Artificial guide star? Moon? Static? Any experts care to comment on t

 

[mikeemmert]

"The word" just in from Mike Brown:<br /><br />"<font color="yellow">Hi Mike --<br />It's a background star. You're looking at the discovery image of <br /> />Dysnomia< rather than that of Eris here. With the adaptive optics on <br />the resolution is so good that the background stars smear after even a <br />relatively short amount of time!<br />Mike<font color="white">".<br /><br />I used, "Famous Photo of Eris "enhanced"" for my subject line. I would venture to guess that this <i>is</i> the most <i>famous</i> photo of Eris, rather than the discovery or HST or Spitzer (which I've never seen) images.</font></font>

 

[mikeemmert]

Good News <img src="/images/icons/cool.gif" /><br /><br />And especially LISTEN UP ALL KIWIS, AUSTRALIANS, JAPANESE, AND SE ASIAN POSTERS:<br /><br />(from e-mail to Mike Brown)<br /><br />"<font color="yellow"> http://www.lunar-occultations.com/iota/2006tno.htm<br /><br />It turns out that, yes, indeed, major Trans-Neptunian<br />Objects will go across stars, blotting them out for a<br />period of time that depends on the TNO's size and the<br />speed of the TNO.<br /><br />We can FINALLY get some of these albedos pinned down!<br /><br />On November 6, 2006, the shadow of 20000 Varuna from<br />the star 2UCAC 40677364 fell across Japan, Asia, SE<br />Asia, and Australasia.<br /><br />Occultations of Quaoar (3 times), Ixion (twice),<br />Chaos, and (my favorite unnamed TNO) 2002 TX300 will<br />occur in the 2008-2010 time period<font color="white">".<br /><br />I think the occultations are done worldwide, but for some strange reason the Kiwis and Australians lucked out, not just on Varuna but on other TNO's as well.</font></font>

 

[3488]

Hi mikeemmert, thank you very much for your kind comments about me. Very much appreciated.<br /><br />You image is pretty good, the enhancement worked well. Dysnomia is well seen at the three O clock position & Eris itself is clearly resolvable.<br /><br />Stellar Occultations will reveal much, particulaly by the same TNO, as that will determine shape, size & rotational rates.<br /><br />I agree. I too very much doubt that Eris will have an atmosphere. It is much too cold. <br /><br />Eris & Sedna IIRC are now the coldest known objects in our solar system, taking that title away from Triton.<br /><br />Quaoar, is still a real mystery. The surface appears to be covered in crystalline ice, almost certainly cryovolcanic activity, or could an impact generate that sort of heat?? Pluto's moon Charon too, also has copious amouts of crystalline ice. <br /><br />We know that Miranda, Ariel, Titania & Oberon, all have crystalline ice in varying amounts & Voyager 2 showed why very well indeed, that all four objects have seen much action in the past (Miranda, co orbital impacts) Ariel & Titania internal tectonic activity & cryovolcanism & Oberon localised cryovolcanism!!! <br /><br />Umbriel being the odd one out, showing little if any internal geological activity, but does appear to have a 'bulls eye' at the top of the disk.<br /><br />2003 EL61 is a real odd ball. Was its weird shape frozen into it due to an even faster rotation in the past?? The large moons, are they too covered in crystalline ice?? Getting serate spectra of all three objects will reveal much. Are 2003 EL61's moons chips of the old block, did they form around 2003 EL61, or are they imposters captured from else where within the Kuiper Belt?? It is time that 2003 EL61 & her moons have been given proper names. If the moons are cryovolcanically active, it would explain the source of the crystalline ice on EL61 itself. Do we know the orbits of the moons? Perhaps this system has few impact crat <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[alokmohan]

Eris has fascinated us as if we are living in Eris.

 

[mikeemmert]

Howdy folks <img src="/images/icons/smile.gif" /><br /><br />I have joined the IOTA discussion board, mainly to find out anything I can about Varuna. Well, that occultation has passed. But I have perused some of the other occultations and one is coming up January 19th.<br /><br />"<font color="yellow">2001 QF298 is a trans-Neptunian object that resides in the Kuiper belt. It was discovered on August 19, 2001 by Marc W. Buie. It is in a 3:2 orbital resonance with Neptune similar to Pluto<font color="white">".<br /><br />The data sheet lists it as 505 km in diameter. I don't know how they got that diameter, but if they used the thermal emission/visible magnitude method, there is a much better way. On January 19, 2007 (this month), the object will pass in front of a star:<br /><br />"<font color="yellow">2007 Jan 19 10 54.1 380 0.01 17.3s 11.4 9.8 53 2UCAC 29760359 2001 QF298 202 e.Australia, Japan<font color="white">".<br /><br />This is an opportunity to at least get the diameter of a large KBO. Later this year will be occultations of 10199 Chariklo, a Centaur orbiting between Satrun and Uranus (not quite a KBO, but of interest; it may have once been one) and 47171 1999 TC 36, which has a moon.<br /><br />2008 will be a better year for occultations, with the famous KBO's Chaos, Ixion (twice!), and Quaoar.<br /><br />2009 will see occultations of Quaoar and Chariklo and my favorite as-yet-unnamed TNO, 2002 T</font></font></font></font>

 

[alokmohan]

Are KBO and Tno related?

 

[MeteorWayne]

KBO (Kuiper Belt Object) is a subset of TNO (Trans Neptunian Objects) just as Plutino is a subset of both. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>