super-earth
esiegel | August 9, 2013“Next to reasoning, the greatest handicap to the optimum development of Man lies in the fact that this planet is just barely habitable. Its minimum temperatures are too low, and its maximum temperatures too high. Its day is not long enough, and its night is too long... These factors encourage depression, fear, war, and lack of vitality. They describe a planet, which is by no means perfectly devised for the nurturing or for the perpetuation of a higher intelligence.” -James Thurber
It's been just about three years, now, since the first announced discovery of a planet in another star system…
esiegel | July 11, 2012"It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small." -Neil Armstrong
Here on our little wet rock in our Solar System, we often remind ourselves what a small world Earth actually is. The farther out in space we reach, the more this appears to be true.
Image credit: NASA / Apollo 11, taken by Command module pilot Michael Collins.
The Earth is the largest of the four inner, rocky planets in our Solar System, at more than 12,000 km in…
esiegel | June 22, 2012"Some prophecies are self-fulfilling
But I've had to work for all of mine
Better times will come to me, God willing
Cause I can't leave this world behind" -Josh Ritter
You sure can't leave this world behind. At least, not very easily. The reason for it, of course, is gravity.
Image Credit: Physclips, via the University of New South Wales' School of Physics.
Here on the surface of the Earth, the gravitational potential well is pretty large; large enough that there's no easy way off. Sure, you can pour a huge amount of energy into a rocket to try and overcome this gravitational potential…
catdynamics | January 10, 2011Kepler 10-b, announced at the Annual meeting of the American Astronomical Society today, has a mass of 4.6 Earth masses and a radius of 1.4 Earth radii. Density of 8.8
Kepler 10b: Exoplanet Catalog
Kepler Mission website - 700 more to go.
Kepler 10b - Mission catalog data
20 hour orbital period around an old, slightly metal poor ( Z ~ -0.15) G dwarf.
500 light years away.
Kepler 10b - artist's conception
Paper is Batalha et al (ApJ in press) - expect it will be on arXiv tonight.
Lightcurve ought to be interesting, will really tell us how deep Kepler is going to go.
11th magnitude host star,…
catdynamics | October 12, 2010Canadian-French Hawaii Telescope transit observations show super-earth is probably a mini-neptune
Ray Jay reports from Torino that his group has CFHT observations on GJ 1214b transits, suggesting it has a H/He atmosphere, and is therefore probably not a "super-earth", but more likely an ice giant with neptune like atmosphere.
This is interesting, suggesting indirectly the planet migrated from beyond the ice line and did some gas accretion onto its core before reaching the inner system.
Looking forward to seeing the paper.
catdynamics | October 11, 2010There are reports from Torino about HARPS observations of Gliese 581(g)
Vogt et al reported on additional possible planets in the multi-planet low mass Gliese 581(g) system.
In particular they showed a ~ 3 sigma detection of a possible 3+ earth mass planet in a circular orbit with an orbital period consistent with a temperate surface.
The paper used a combination of historic Keck data, published HARPS data up through 2008 and new high cadence Keck data.
There was some concern when the paper came out that the False Alarm Probability was underestimated (see Cumming et al for discussion of…