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eburacum45
2010-Jan-15, 06:40 PM
I mentioned these ultrahot objects in another thread; does anyone know what they should be called? The link merely calls them 'objects of interest'.
http://news.discovery.com/space/blazing-stellar-companion-defies-explanation.html

John Jaksich
2010-Jan-16, 03:41 AM
Hi --I'll take a stab at it-->

this is supposedly an object(?) that has been discovered by the "Kepler" probe and is (supposedly?) akin to our own rocky planet ----only we (?) may be stumbling upon a different mode of earth-like planet formation. This planet started as a gas giant and is slowly losing it's gaseous outlayers only to produce a "large--and hot" rocky planet.

Here are a couple of different links:

physorg.com (http://www.physorg.com/news182023632.html)

http://kepler.nasa.gov/

**************
Even though -- there are other modes of planet formation proposed-- (there is probably no standard mechanism for every planet?...that's my take on it...

Cheers

eburacum45
2010-Jan-16, 05:00 AM
Nope; these new objects are to hot to be planets. CoRoT-7b has a temperature of about 3600 degrees Fahrenheit (2300K), but the new objects are at 70,000 degrees Fahrenheit (40,000K) They appear to be some kind of expanded white dwarf.

John Jaksich
2010-Jan-16, 05:06 AM
Nope; these new objects are to hot to be planets. CoRoT-7b has a temperature of about 3600 degrees Fahrenheit (2300K), but the new objects are at 70,000 degrees Fahrenheit (40,000K) They appear to be some kind of expanded white dwarf.

Thank you for the correction!

eburacum45
2010-Jan-16, 06:35 AM
Trouble is, I can't imagine what to call such an 'expanded dwarf'. It seems a bit of an oxymoron somehow.

John Jaksich
2010-Jan-16, 06:52 AM
It will obviously garnish more observation time (IMHO)-----> but ...

As an aside: when, as a student, I was studying mechanistic organic chemistry...there were so many phenomena that seemed incomprehensible to me i.e. ionic species that exist in a near-state of suspended electronic motion...non-classical carbenium ion species as they are currently termed...that in the present case of this "dwarf" it might defy terminology until it is further studied.


Thanks for pointing-out this phenomena.

noncryptic
2010-Jan-16, 07:28 AM
The article says no wobble has been measured yet. So could it be a hot spot on the star? It would not be the first time that a companion turns out not to be a companion.

eburacum45
2010-Jan-17, 02:35 AM
The variations they are detecting in these stars' luminosities are very small, so perhaps that is possible. But I think there should be distinct and detectable differences between the light curve of a star with a large sunspot, and a star with a much smaller and hotter star-like object in orbit around it.

Hungry4info
2010-Jan-17, 02:08 PM
The mass has been at least constrained.

Kepler Observations of Transiting Hot Compact Objects
Jason Rowe, W. J. Borucki, D. Koch, Kepler Team
NASA Ames Research Center.


We present Kepler lightcurves of two A spectral class stars which show hot, compact transiting companions. Our analysis of 45 days of high duty cycle, ultra precise photometry show the companions have radii of 40% and 90% that of Jupiter based and effective temperatures greater than 10 000K based on the transit and eclipse lightcurve profiles. These objects have properties similar to white dwarfs as they are compact and hot. The lightcurves also suggest the companions have masses less than 10% of the Sun. Kepler was selected as the 10th mission of the Discovery Program. Funding for this mission is provided by NASA, Science Mission Directorate.

A star spot would make a recognizably different photometric pattern.

See
http://www.bautforum.com/space-astronomy-questions-answers/99329-planet-hunting-kepler.html

George
2010-Jan-17, 08:45 PM
It sounds a little like a blue dwarf. These aren't suppose to exist as the universe is too young for this phase in a red dwarf's life. Of course, perhaps something happened to another star that blew-off the shell and kicked it into a blue dwarf. I don't know, however, what blue dwarf temperatures are suppose to be.

Apprently, and I could be wrong, the blue dwarf star is fully convective and temparature increases do not diminish opacity. I think this means they become hot -- bluish-white hot. I'm specualting a little. [After all, we're still working on the "yellow dwarf" thing. ;)]

ngc3314
2010-Jan-17, 10:20 PM
Looking back at planetary nebulae, planets versus dwarf planets, asteroids/planetoids/minor planets, early/late type stars and galaxies, and so on, maybe this time we can hold off coming up with a class name until we have a better idea what they are..

George
2010-Jan-17, 11:55 PM
Looking back at planetary nebulae, planets versus dwarf planets, asteroids/planetoids/minor planets, early/late type stars and galaxies, and so on, maybe this time we can hold off coming up with a class name until we have a better idea what they are.. Yeah! I'll be less distracted by such inviting trivia. :)

Science is self-correcting so we should learn from our mistakes. Perhaps some sort of obvious preliminary designation be given such objects, such as UAO (Unidentified Astronomical Object) followed by a subclass to distinguish it between, say, apparent stellar or extended objects. Then followed with the numerical tag for its RA & Dec to the nearest minute.

Frankly, I think the reinstitution of a LGM catalog would be nice, though only serving as a temporary designation. [I'm becoming more fond of the various color conundrums.] ;)

[Of course, y'all could call them "George" and let the French and Germans come up with something more appropriate [once the hard data comes in]. I'm sure they'll be more careful this time. ;)]