A ghost of Christmas past [ Kuiper Belt Object 2009 YE7 discovered ]

Mike Brown's Planets 'blog ^ | Tuesday, December 29, 2009 | Mike Brown

[SunkenCiv]

Our understanding of the Kuiper belt has changed dramatically in these past five years. The best example of this change comes, I think, from the discovery of a large Kuiper belt object that was announced just a few days ago... But, by decoding the numbers, I could tell it was something that had just been discovered a few days before. Like anyone else, my first attempt to know more was a quick trip to Google.

Ah ha! A new large Kuiper belt object found from a telescope Chile, by David Rabinowitz! Yes, the same David Rabinowitz from the Haumea discovery. He has moved on to Chile to try to make newer discoveries from there, discoveries in parts of the sky that we didn't look at back when we were working at Palomar Observatory outside of San Diego.

Based on preliminary information, it looked likely the 9th largest Kuiper belt object ever found. David was clearly on to something good here...

Based on its brightness it might well be a perfect size to test one of my new theories about medium-sized Kuiper belt objects. I feel like I now understand the largest objects, and I fear that I will never understand the smallest objects, but the middle ones are within grasp, if we can just find a few more to test some pet theories about them. For 2009 YE7 to be a good candidate for my theory we need to know if it has a moon, what color it is, and what materials are on its surface. Then we'll see. I started thinking about where 2009 YE7 is in the sky, what telescopes I could use to point at it, how to time the observations.

[SunkenCiv]

Read some background at Mike Brown's Caltech homepage, and very damned little at the homepage of 2009 YE7's discoverer's David L. Rabinowitz.

[SunkenCiv]

Chunk of the wiki-wacky-pedia entry:

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2009 YE₇

Discovery[1]
Discovered by	David Rabinowitz
Discovery date	December 17, 2009(?)
Designations
MPC designation	2009 YE7
Minor planet category	TNO Cubewano[2] Haumea family?[3]
Orbital characteristics[2]
Epoch December 15, 2009 (2455180.5)
Aphelion	51.1 AU (Q)
Perihelion	35.9 AU (q)
Semi-major axis	43.5 AU (a)
Eccentricity	0.17
Orbital period	287 yr
Mean anomaly	180° (M)
Inclination	29.2°
Longitude of ascending node	138°
Argument of perihelion	96°
Satellites	?
Physical characteristics
Dimensions	440[4]-945[5] km[2][6]
Albedo	assume 0.7 to 0.15
Apparent magnitude	~20(?)(JPL Horizons)
Absolute magnitude (H)	2.8[2]

2009 YE₇ is a trans-Neptunian object with an absolute magnitude of 2.8.^[2] This qualifies it as a dwarf planet candidate. It was discovered by David Rabinowitz on December 17, 2009 at the La Silla Observatory in Chile. 2009 YE₇ is the first bright KBO found from the southern hemisphere.

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[SunkenCiv]

Same wiki-wacky-pedia entry with the links clarified:

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2009 YE₇

Discovery[1]
Discovered by	David Rabinowitz
Discovery date	December 17, 2009(?)
Designations
MPC designation	2009 YE7
Minor planet category	TNO Cubewano[2] Haumea family?[3]
Orbital characteristics[2]
Epoch December 15, 2009 (2455180.5)
Aphelion	51.1 AU (Q)
Perihelion	35.9 AU (q)
Semi-major axis	43.5 AU (a)
Eccentricity	0.17
Orbital period	287 yr
Mean anomaly	180° (M)
Inclination	29.2°
Longitude of ascending node	138°
Argument of perihelion	96°
Satellites	?
Physical characteristics
Dimensions	440[4]-945[5] km[2][6]
Albedo	assume 0.7 to 0.15
Apparent magnitude	~20(?)(JPL Horizons)
Absolute magnitude (H)	2.8[2]

2009 YE₇ is a trans-Neptunian object with an absolute magnitude of 2.8.^[2] This qualifies it as a dwarf planet candidate. It was discovered by David Rabinowitz on December 17, 2009 at the La Silla Observatory in Chile. 2009 YE₇ is the first bright KBO found from the southern hemisphere.

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[SunkenCiv]

• JPL Small-Body Database Browser -- 2009 YE7

this is also a potential catastrophism topic, but I'm going to bed.

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[JoeProBono]

[SunkenCiv]

Oddly enough, my search for ANY news item on this discovery came up with this slightly earlier, quite boring discovery of the smallest KBO ever spotted:

Real Occult Science: Hubble Spots Smallest Comet Vagabond by Ray Villard, Wed Dec 16, 2009 02:47 PM ET

[SunkenCiv]

Okay, this time for SURE.

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2009 YE₇

Discovery[1]
Discovered by	David Rabinowitz
Discovery date	December 17, 2009(?)
Designations
MPC designation	2009 YE7
Minor planet category	TNO Cubewano[2] Haumea family?[3]
Orbital characteristics[2]
Epoch December 15, 2009 (2455180.5)
Aphelion	51.1 AU (Q)
Perihelion	35.9 AU (q)
Semi-major axis	43.5 AU (a)
Eccentricity	0.17
Orbital period	287 yr
Mean anomaly	180° (M)
Inclination	29.2°
Longitude of ascending node	138°
Argument of perihelion	96°
Satellites	?
Physical characteristics
Dimensions	440[4]-945[5] km[2][6]
Albedo	assume 0.7 to 0.15
Apparent magnitude	~20(?)(JPL Horizons)
Absolute magnitude (H)	2.8[2]

2009 YE₇ is a trans-Neptunian object with an absolute magnitude of 2.8.^[2] This qualifies it as a dwarf planet candidate. It was discovered by David Rabinowitz on December 17, 2009 at the La Silla Observatory in Chile. 2009 YE₇ is the first bright KBO found from the southern hemisphere.

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[SuziQ]

Astronomy ping!