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Kullat Nunu
2005-Mar-31, 02:13 PM
Direct detection by imaging (http://www.obspm.fr/encycl/GQ-Lup.html) of an extrasolar planet around a young T Tauri star GQ Lupi.

Seems like the preprint (http://fr.arxiv.org/abs/astro-ph/0503691) isn't yet in the arXiv.org so can't say more.

[GQ not CQ, sorry]

Kullat Nunu
2005-Apr-01, 07:03 AM
The preprint is now online. Though I don't understand much of it. #-o

The planet seems to have a mass of 2 times that of Jupiter, radius 1.8 times Jupiter, semimajor axis 103 astronomical units, orbital period about 1200 years and surface temperature as much as 2000 Kelvins. The planet is only a million years old. That's why it's so hot.

sol_g2v
2005-Apr-01, 09:52 AM
Wow that's a big orbit for a planet. Must have a been a massive planetary disk, even though it's only a K7 star.

Hazzard
2005-Apr-01, 10:47 AM
Im still waiting for the discovery of an "Earth-class" planet.

No more gas giants...please! 8)

Kullat Nunu
2005-Apr-01, 12:53 PM
Im still waiting for the discovery of an "Earth-class" planet.

No more gas giants...please! 8)

Patience. Wait a few years...

Romanus
2005-Apr-01, 05:33 PM
Fascinating--it's just a shame that it isn't close enough to its GQ Lupi to make radial velocity measurements practical. Of course, then it would also probably be too close to see, so it's a trade-off.

Doodler
2005-Apr-01, 06:02 PM
Jovian-schmovian, I don't care what kinda planet it is, they bagged one on camera. :)

That's cause for a little celebrating. :)

Kullat Nunu
2005-Apr-01, 06:30 PM
There is still a change that it is actually a brown dwarf as much as 42 times as massive as Jupiter. But probably they have a good reason to think otherwise.

TravisM
2005-Apr-01, 06:38 PM
42? I though you said 2 originally... :-?

April fools? :D

Kullat Nunu
2005-Apr-01, 06:55 PM
42? I though you said 2 originally... :-?

April fools? :D


The value of the mass depends on atmosphere models and could be up to 42 MJ

But I'm pretty sure that they have a good reason to call this a planet.

Ilya
2005-Apr-01, 06:59 PM
The planet seems to have a mass of 2 times that of Jupiter, radius 1.8 times Jupiter, semimajor axis 103 astronomical units, orbital period about 1200 years and surface temperature as much as 2000 Kelvins. The planet is only a million years old. That's why it's so hot.

You realize that 103 AU is the minimum current distance between GQ Lupi and the planet -- it assumes the star-planet line is perpendicular to our line of sight. Most likely it is greater than that.

OTOH, semi-major axis might actually be smaller than the current distance -- if GQ Lupi b has an eccentric orbit, we may have caught it near aphelion. In fact, if GQ Lupi b were flung into its current orbit rather than formed there, that orbit is almost certainly elliptical.

rleyland
2005-Apr-01, 10:28 PM
from CNN:

http://edition.cnn.com/2005/TECH/space/04/01/extrasolar.planet.photo/index.html

with pretty picture

jaeger
2005-Apr-01, 11:41 PM
Patience. Wait a few years...

What we be the technology that would allow us to image smaller planets - more powerful optics, better filtering if the star's light?

tracer
2005-Apr-02, 01:47 AM
Jovian-schmovian, I don't care what kinda planet it is, they bagged one on camera. :)
Yeah -- but in this case, it's only visible because it's 2000 Kelvins and is thus glowing from its own heat.

If it'd been a cold planet -- even one with a 100% albedo -- I doubt it would have reflected enough starlight to have been visible to us.

Tacitus
2005-Apr-02, 02:00 AM
Patience. Wait a few years...

What we be the technology that would allow us to image smaller planets - more powerful optics, better filtering if the star's light?

Here (http://planetquest.jpl.nasa.gov/TPF/tpf_index.html), here (http://planetquest.jpl.nasa.gov/Keck/keck_index.html), and here (http://www.eso.org/projects/owl/), as examples.

I think it will be a race between ground-based observatories, and space-based telescopes.

Kullat Nunu
2005-Apr-08, 12:56 PM
ESO press release: Is this a Brown Dwarf or an Exoplanet? (http://www.eso.org/outreach/press-rel/pr-2005/pr-09-05.html)