Plutino/Cubewano/KBO/Trans Neptunian Object addon?

Malenfant · Post #1by **Malenfant** » 19.08.2006, 15:48

Is there an addon for Celestia that shows ALL of the known "outer solar system asteroids"? By which I mean the plutinos, the cubewanos, the KBOs, the oort cloud objects and all that other small stuff out there beyond Neptune?

If so, can someone point me to it please?

Malenfant · Post #2by **Malenfant** » 19.08.2006, 18:14

http://cfa-www.harvard.edu/iau/lists/TNOs.html

I found this list of known TNOs (TransNeptunian Objects), so that's a good data source... is there a program around that can convert that list to a Celestia ssc file?

Post #3by **selden** » 19.08.2006, 18:33

You need more than just the TNO list:
2003 UB313 is classified as a Centaur, for example, and their Others list includes the near-Oort bodies with really large SMAs.

I've just finished converting CfA's current tnos, others and centaurs lists into SSC format. I'm not really happy with the results: the radii depend on the albedos and on their H (absolute magnitudes) which are not well known. I'm not about to try to hand craft them, though.

See the Web page
http://www.lepp.cornell.edu/~seb/celest ... anets.html
in the "others" section.

Malenfant · Post #4by **Malenfant** » 19.08.2006, 19:56

That's good enough for me, I just wanted to see their orbits

.

Huh. It really is a proper belt out there isn't it... Thanks!

ajtribick · Post #5by **ajtribick** » 19.08.2006, 20:25

I was under the impression that "centaur" was used to refer to objects located between Jupiter and Neptune. How does 2003 UB313 qualify?

Malenfant · Post #6by **Malenfant** » 19.08.2006, 21:54

Er, yeah actually - I wondered the same thing...

EDIT: Actually, it's an SDO (Scattered Disk Object) - but the MPC list for these objects is for Centaurs and SDOs ( http://cfa-www.harvard.edu/iau/lists/Centaurs.html ). But this isn't a Centaur. See http://en.wikipedia.org/wiki/Scattered_disc for definition.

Also, Selden - when I look at the orbits from above with the labels on, there seems to be a horsehoe pattern - there's about 20 degrees of the TNO orbits where there are no asteroids right now. Is that real? Some kind of observational bias or something? Or is there a problem with the labels, or is the data incomplete?

You can see this roughly at the 8 o'clock position here (the time is today, I'm 350 AU above Sol at lat 90, lon 0):

ajtribick · Post #7by **ajtribick** » 19.08.2006, 23:46

Ok, thanks for that... thought there'd been some kind of huge reclassification or something. Seems to be quite the season for that kind of thing.

That gap seems to be located close to Neptune, which may have something to do with it...

Malenfant · Post #8by **Malenfant** » 20.08.2006, 01:39

It seems to get filled up as you fast forward time... I just thought it was odd. Doesn't seem to track Neptune though.

Kolano · Post #9by **Kolano** » 20.08.2006, 03:34

You might need to set the time to around the time the data was collected to acertain the cause.

ajtribick · Post #10by **ajtribick** » 20.08.2006, 10:30

I'd suspect the orbital elements keep changing thanks to interactions with Neptune... those elements aren't going to stay accurate for the duration of an orbit.

Post #11by **selden** » 20.08.2006, 17:46

A surprising fraction (~20%) of the TNOs seem to be in a 3:2 resonance with Neptune. A list of 199 "plutinos" is now available, too. It includes all of the TNOs which have a semi-major axis value within 0.5 AU of Pluto's SMA. I chose that value because it it seems to be just slightly past the tail of the distribution and seems to correspond to the maximum value shown in David Jewitt's page on plutinos at http://www.ifa.hawaii.edu/~jewitt/kb/plutino.html

The updated Zip archive is down near the bottom of the Web page http://www.lepp.cornell.edu/~seb/celest ... anets.html