Distant world circles tiny star.

[Notebook]

http://news.bbc.co.uk/1/hi/sci/tech/8077302.stm

At one-twelfth the mass of the Sun, VB 10 is tiny; though the star is more massive than its planet, it would have about the same girth, experts say.

N.

 

[RisingFury]

If we get really good at measuring these slight wobbles then we can also get very precise distances to other stars.

 

[Notebook]

Two to six times a year, for the past 12 years, Dr Pravdo and Stuart Shaklan, also from JPL, have bolted their Stellar Planet Survey instrument on to the Palomar Observatory's 5m Hale telescope to search for planets.

Dedication, or what?

N.

 

[RisingFury]

Dedication, or what?

N.

It takes a lot of it when searching for something like this, especially from Earth.

Our current method of detecting planets by their mass is with the use of spectrograph. That detects the forward and back movement of the star. But this method actually looks for the left-right wobble... But that is insanely difficult to do from Earth because of the pesky atmosphere. Every star kinda dances around as light travels through the atmosphere... and that makes accurate measurements difficult as hell.

 

[Notebook]

The newfound planet, VB 10b, is a gas giant with a mass six times that of Jupiter that lies 20 light-years away. Scientists think the planet's own internal heat would give it an Earth-like temperature.
Lead author Steven Pravdo, from Nasa's Jet Propulsion Laboratory in Pasadena, US, commented: "We found a Jupiter-like planet at around the same relative place as our Jupiter, only around a much smaller star.

A Jupiter like Planet! Wonder what happens if they find a Pluto type object...
Amazing stuff.
N.

 

[RisingFury]

A Jupiter like Planet! Wonder what happens if they find a Pluto type object...
Amazing stuff.
N.

None of our detection methods are sensitive enough to detect an Earth sized planet yet. 1.9 Earth masses is the smallest one so far.

Pluto is about 0.02% mass of Earth...

It's pretty safe to assume such objects are out there, but we just can't detect them yet.

 

[Notebook]

Only a few orders of magnitude to go...

N.

 

[RisingFury]

Erm... I think we'll need to find a better method of detecting planets. Increasing accuracy won't do.

The surface of the star isn't stationary. It kinda moves like boiling water. That makes accurate measurements impossible cos you can't really tell if the star is moving or is that just it's surface moving a bit.


Directly looking at a star and hoping to see a planet is not really effective either. We're blinded by the light from the star and cannot see the planets. There's only one object that's so far been identified that might be a planet, with an orbital period of some 140+ years. It's still not clear if it's a planet or just a flaw in the image...


One chance would be to have a Kepler like setup taking spectrometry readings and looking if they change of composition over time, but I'm not sure that would pick up planets without atmosphere and there's a possibility that we wouldn't be able to get a difference from objects as small as Pluto. So far we've used that approach to find atmospheric compositions of planets.

 

[Artlav]

I wonder, if aimed right, will the best of our telescopes resolve an earth-sized planet near a nearby star?

 

[Notebook]

I thought there had been some imagery of an exoplanet? Or was it inferred from the data. I'll have a look.

N.

---------- Post added at 21:13 ---------- Previous post was at 21:11 ----------

Probably the one I was thinking about:-

http://blogs.discovermagazine.com/badastronomy/2008/11/13/huge-exoplanet-news-items-pictures/

N.

 

[RisingFury]

I wonder, if aimed right, will the best of our telescopes resolve an earth-sized planet near a nearby star?

No. The light of the star just blinds the telescope.


http://blogs.discovermagazine.com/badastronomy/2008/11/13/huge-exoplanet-news-items-pictures/ <=== This image that Notebook posted is the only one I know of that is possibly a planet. I've seen two images compiled into one, where you see a tiny shift in position from 2004 to 2006. Another image has been created in 2008 and I'm waiting for the compilation to be released...



The second image shows two really young planets. For one, the planets are still glowing from the heat of creation... and it's also likely that accretion hasnsn't finished yet, so they might still be giant blobs of hot stuff that will further collapse and lose size. They're easy to detect in infra red this way.


So you really have to be lucky to actually see another planet. We'd have to develop some really outstanding methods to actually separate the light of the star from the background and the planets for this to become a useful way of finding planets. So far the Kepler approach and the spectrometry approach seem to yield far better results.

You can see the huge shine from the star... you can also see the star has been cut out of the image. This time we're lucky. The planet is huge and orbits very far away from it's star. Usually we just wouldn't be able to see it...

---------- Post added at 10:06 PM ---------- Previous post was at 09:57 PM ----------

Oh, in the second picture on the site Notebook posted, you can see very young planets. Nobody really knows how long the accretion process actually lasts, so these two planets might still be just giant blobs of stuff that haven't fully collapsed into planets yet.

But the accretion is well under way - or very soon after finishing, so the planets are incredibly hot, which makes them shine in the infra red part... and are therefore easy to detect.

 

[tblaxland]

Another image has been created in 2008 and I'm waiting for the compilation to be released...

Here is the image from Keck in 2008, for reference:
http://en.wikipedia.org/wiki/File:HR_8799_planetary_system_photo.jpg

I would really like to see that compilation too.