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Extrasolar Planets

arg-fallbackName="Anachronous Rex"/>
Just thought I'd say thanks for doing all this Rigel.

I'm not much of an astronomer, so I don't really feel qualified to comment on any of it, but it is all terribly interesting stuff.
 
arg-fallbackName="televator"/>
I think it's kinda funny that they use the 5 pointed image of a star to mark the star's position....it's kinda cute. lol!
 
arg-fallbackName="RigelKentaurusA"/>
arg-fallbackName="RigelKentaurusA"/>
At least two planets (with evidence of a third) orbiting the eclipsing polar star HU Aqr.
http://arxiv.org/abs/1103.2005
 
arg-fallbackName="RigelKentaurusA"/>
Three new hot Jupiters from super-WASP, including WASP-43 b, setting a record for the planet with the smallest known semi-major axis (0.014 AU). Also, WASP-35 b and WASP-48 b, and independent confirmation of HAT-P-30 b (Super-WASP designation WASP-51 b), link.
 
arg-fallbackName="RigelKentaurusA"/>
kenandkids said:
I really enjoy looking through these, thank you for putting them up =-)
Click to expand...

I'm glad you enjoy them! :)


In 2004, 55 Cancri was found to host a fourth planet of, what was at the time, very low mass (was believed to be ~12 Earth-masses then, but now understood to be ~8). Now, it has been found to transit! (a fifth planet was discovered later)

A Super-Earth Transiting a Naked-Eye Star
http://arxiv.org/abs/1104.5230


This is pretty darned major. Besides having a (barely) naked-eye star to be able to point to and be able to say something about the mass and radius of its planet, this star is a couple magnitudes brighter than any previous transiting planet host thus far. This will make 55 Cancri's innermost, transiting planet very important in studying such super-Earth type worlds. The photometric light curve was a bit noisy, but it points to a high-density planet, with probably a significant metal content.
 
arg-fallbackName="RigelKentaurusA"/>
RigelKentaurusA said:
The photometric light curve was a bit noisy, but it points to a high-density planet, with probably a significant metal content.
Click to expand...
Well.. maybe.

Detection of a transit of the super-Earth 55 Cnc e with Warm Spitzer
http://arxiv.org/abs/1105.0415

Spitzer photometry suggests a considerably larger radius, requiring a volatile envelope. The thing may be more a mini-Neptune than a hard rock. More observations are needed to explain this disagreement between the optical and infrared radius for the planet.
 
arg-fallbackName="RigelKentaurusA"/>
A second companion confirmed orbiting HIP 5158
http://arxiv.org/abs/1105.1150v1

Not exactly a new planet discovery per se, but pretty cool nonetheless. HST observations spatially resolve a debris disk at HD 92945, revealing an inner ring at ~60 AU and an outer disk extending out to ~140 AU, where it is truncated.

HD 92943 joins an increasing list of systems with resolved debris disks that have signs of planet formation.

HD92945_Disk.jpg


Hubble and Spitzer Space Telescope Observations of the Debris Disk around the Nearby K Dwarf HD 92945
http://arxiv.org/abs/1105.0888v1
The dynamical causes of the disk's morphology are unclear, but recent models of dust creation and transport in the presence of migrating planets indicate an advanced state of planet formation around HD 92945.
Click to expand...
 
arg-fallbackName="RigelKentaurusA"/>
Memeticemetic said:
Dude, how the hell is a hobbit gonna walk all the way to that?
Click to expand...
That's not the first HST image of a debris disk for which that joke has been made :lol:
Hubble+image+of+a+ring+of+dust+around+star+Fomalhaut.jpg

(Fomalhaut)
 
arg-fallbackName="RigelKentaurusA"/>
WASP-44b, WASP-45b and WASP-46b: three short-period, transiting extrasolar planets
http://arxiv.org/abs/1105.3179
 
arg-fallbackName="RigelKentaurusA"/>
RigelKentaurusA said:
More observations are needed to explain this disagreement between the optical and infrared radius for [55 Cnc e]
Click to expand...
Turns out the MOST team had an error in their data processing pipeline, which they describe here, which caused them to underestimate the transit depth of the planet. 55 Cnc e is found to have a larger radius, consistent with the Spitzer results, and suggestive of a considerable fraction of volatiles or gases.

They have a new version of their paper taking this into account.
A Super-Earth Transiting a Naked-Eye Star (v2).
http://arxiv.org/abs/1104.5230v2

Also, an interferometric radius determination for the host star's radius leads to a model-independent determination of 55 Cnc e's radius, and refinement of the star's luminosity and traditional habitable zone. The fourth planet from the star (55 Cnc f) is found to spend some time in the habitable zone.

55 Cancri: Stellar Astrophysical Parameters, a Planet in the Habitable Zone, and Implications for the Radius of a Transiting Super-Earth
http://arxiv.org/abs/1106.1152
 
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