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selvaarchi
2015-Nov-12, 02:18 PM
Astronomers have found a dwarf planet three times farther away from the Sun than Pluto, making it the most distant known object in the solar system. Designated V774104, (http://astronomynow.com/2015/11/12/newly-discovered-dwarf-planet-is-solar-systems-most-distant-object/) the trans-Neptunian object is 500 to 1000 kilometres in diameter half the size of Pluto and currently lies 15.4 billion kilometres (9.6 billion miles) or 103 astronomical units (AU) from the Sun, but its exact orbit is yet to be determined.

Swift
2015-Nov-12, 02:27 PM
Wow, very cool (no pun intended).

I did find this sentence at the end of the article amusing:


At the time of V774104’s discovery, only the Voyager probes, Pioneer 10 and some long-period comets are known to be farther from the Sun.
I assume they are only including objects directly associated with our solar system. Last I heard, all the rest of the stars in the universe, among other things, were known to be farther from the Sun too.

profloater
2015-Nov-12, 02:36 PM
I think v774104 is quite catchy but if it is another dwarf planet, might it be happy under a suitable name like sneezy or dozy?

Swift
2015-Nov-12, 03:14 PM
I think v774104 is quite catchy but if it is another dwarf planet, might it be happy under a suitable name like sneezy or dozy?
Yes, and after they work through the Snow White names that can start with Gimli, Thorin, etc.

KaiYeves
2015-Nov-12, 08:58 PM
I know they're having trouble finding mythological names for all of them, but I like that Sedna, Makemake, and Quaoar branched out beyond Greco-Roman. Maybe another Polynesian deity?

Edit: Actually, they could satisfy both my suggestion and the ones above with "Menehune", after the mythical dwarfs from Hawaiian tradition!

parallaxicality
2015-Nov-16, 05:14 PM
I don't get its designation; usually minor planets are pre-designated titles like "2003 BS101" or something like that.

antoniseb
2015-Nov-16, 05:30 PM
Note that Sedna is closer than this object now, but does spend most of its orbit further away than V774104. There is a good chance that there are more objects like this even further out. Mid and far infrared surveys of the future will help spot them.

StupendousMan
2015-Nov-16, 05:51 PM
It may not have an ordinary designation because its discoverers have not yet provided any data on its position and motion to the Minor Planet Center.

dtilque
2015-Nov-28, 10:21 AM
It may not have an ordinary designation because its discoverers have not yet provided any data on its position and motion to the Minor Planet Center.

They have to have enough observations to determine the orbital parameters. Apparently, they haven't been able to find any precovery images, no doubt due to its faintness. Without an orbit, the MPC doesn't give a temporary designation. They'll have to follow it for a year or so to get enough observations.

I noted they said they had several other objects in the same region that they're following. By same region, they meant around 80 to 90 AU distance. They didn't give any other details, but I assume the same applies to them.

BTW, this thread could go in the Kuiper Belt forum. That forum is rather moribund; it should either be used or shut down.

parallaxicality
2015-Nov-28, 11:13 AM
This forum has two many subforums anyway. Just navigating the main page is getting difficult. If forums are moribund, they should just be merged.

Back on topic, is there any new data on its orbital perimeters?

StupendousMan
2015-Nov-28, 09:43 PM
I wrote in this thread on Nov 16, based on a message from an astronomer I know who studies asteroids,



It may not have an ordinary designation because its discoverers have not yet provided any data on its position and motion to the Minor Planet Center.


to which dtilque replied


They have to have enough observations to determine the orbital parameters. Apparently, they haven't been able to find any precovery images, no doubt due to its faintness. Without an orbit, the MPC doesn't give a temporary designation. They'll have to follow it for a year or so to get enough observations.


Can you provide any evidence that the discoverers have provided their measurements of the object to the MPC, or to any other astronomers? I just now went to the MPC's web site and tried to find the reported positions for the object. I'm not a regular user of the site, so I may not have looked in the right place, but I couldn't find any information on it. If anyone else can, please let me know how to do it.

I note that the Wikipedia entry for this object also states that the positions have not been made public.

dtilque
2015-Nov-29, 10:05 AM
I don't know whether or not they've given any info to the MPC. I just know that there have to be enough observations to calculate an orbit before the MPC will assign an temporary name. And from what I've read, it'll take about a year of observations to get those.

As for the location, I can understand them not giving that out. Remember the controversy over K40506A/Santa/Haumea? They don't want someone stealing their discovery, as happened with that object. If others know where it is, they can observe it and possibly find precoveries. Then someone else could beat them to calculating an orbit and get credit. The surprising thing is that they announced it before getting the orbit. Now they have to be careful not to let the location be accidently posted to the web, as happened with K40506A.

StupendousMan
2015-Nov-29, 06:29 PM
A description of the naming process for minor planets is given at

http://www.minorplanetcenter.net/iau/info/HowNamed.html

Note that it is NOT necessary "to calculate an orbit before the MPC will assign a temporary name." Instead, if one can provide two nights of observations, and those observations cannot be tied to a known object, then the MPC will provide a temporary name.

The puzzle here is that the MPC did provide a name, but it appears that the observations have not been made available to other researchers. This is contrary to the usual practice.


Remember the controversy over K40506A/Santa/Haumea? They don't want someone stealing their discovery, as happened with that object.

Yes, I remember that situation. I wasn't aware that anyone had "stolen" the object -- it was always in the sky, visible to anyone who looked. It still is there, in fact.



The surprising thing is that they announced it before getting the orbit. Now they have to be careful not to let the location be accidently posted to the web, as happened with K40506A.

Yes, if only they had not made any announcements until they could provide a record of their observations to other scientists. Isn't that how science is supposed to work?

dtilque
2015-Dec-02, 09:45 AM
A description of the naming process for minor planets is given at

http://www.minorplanetcenter.net/iau/info/HowNamed.html

Note that it is NOT necessary "to calculate an orbit before the MPC will assign a temporary name." Instead, if one can provide two nights of observations, and those observations cannot be tied to a known object, then the MPC will provide a temporary name.

OK, I guess I got the wrong impression from reading Mike Brown's book about Pluto. He typically waited quite a while (roughly a year) before announcing his discoveries, so he and his team could do some research other than just finding the object. One of the team leaders that announced this new object was on his team back then.


The puzzle here is that the MPC did provide a name, but it appears that the observations have not been made available to other researchers. This is contrary to the usual practice.

The name V774104 is not one given by the MPC, unless they've changed the format of their naming conventions. And the pages you linked to do not indicate they have.




Yes, I remember that situation. I wasn't aware that anyone had "stolen" the object -- it was always in the sky, visible to anyone who looked. It still is there, in fact.

I didn't say the object was stolen. I said the discovery was stolen. That is, credit for the discovery went to someone who didn't actually discover it. Or at least that's the way it was going to go until they found that someone from the "discoverer's" location had accessed observation logs before they announced their discovery.

StupendousMan
2015-Dec-03, 12:17 AM
The name V774104 is not one given by the MPC, unless they've changed the format of their naming conventions. And the pages you linked to do not indicate they have.

The link I supplied above,

http://www.minorplanetcenter.net/iau/info/HowNamed.html

states that "provisional designations" will be made as described at a second page,

http://www.minorplanetcenter.net/iau/info/OldDesDoc.html

The name "V774104" is a provisional designation.

dtilque
2015-Dec-04, 11:40 AM
http://www.minorplanetcenter.net/iau/info/OldDesDoc.html

The name "V774104" is a provisional designation.

You obviously didn't bother to read that page. It says that provisional designations start with the year of discovery, followed by two letters, and then (usually) a subscripted number, although often not subscripted due to orthographic limitations. In common use the year number is often omited. I've never seen the subscripted number be more than 3 digits, although it's possible it could. (A 4-digit number would mean that more than 25000 objects had been given provisional designations in a half-month period. A 5-digit number would be 10 times that and 6 digits 10 times the 5-digit rate. Not saying 4 or more digits are impossible, but I don't think we're discovering objects that quickly yet.)

V774104 does not follow that pattern even if the year is omited; it has only one letter. It's probably a designation by the discoverers.

StupendousMan
2015-Dec-04, 11:54 PM
dtilque is right: the name "V774104" does not follow the rules for "packed provisional names" assigned by the IAU. Those names are described on the web page I linked above, but I did not read it carefully. My apologies; thanks to dtilque for pointing out the mistake and giving the right answer. Those names have forms like this:

K99AJ3Z or J95F13B or T1S3138

I did spend some time trying to read other MPEC web pages carefully, and came across this tidbit: at the URL

http://www.minorplanetcenter.net/iau/info/Astrometry.html

under the heading Do I need to identify objects?, there is the following text describing temporary designations which may be provided by the observer when reporting observations to the MPC:


Observer-assigned temporary designations should be six characters or less long, and begin in column 6 of the observational record.

So, if this name was provided by the observers, they appear not to have followed the rules.

I just can't figure this out. Rats. I suppose people will eventually tell the story ....