On the habitability of HD 85512 b

HD 85512 Discovery paper here.

A Habitable Planet around HD 85512?
http://arxiv.org/abs/1108.3561

Quote :

Aims: In this study we assess the habitability of HD85512b, a 3.6M_Earth planet orbiting a K5V star. The radial velocity data and orbital parameters for HD 85512 b have just been published, based on data from the dedicated HARPS-upgrade GTO program. Methods: This paper outlines a simple approach to evaluate habitability of rocky planets from radial velocity (RV) searches by using atmospheric models of rocky planets with H2O/CO2/N2 atmospheres, like Earth. We focus our analysis on HD 85512 b. To first order the limits of the Habitable Zone depend on the effective stellar flux distribution in wavelength and time, the planet's Bond albedo, and greenhouse gas effects in this approach. We also discuss the dependence of habitability on the measurement accuracies. Results: We provide a simple set of parameters which can be used for evaluating current and future planet candidates from RV searches for their potential habitability. We find that HD 85512 b could be potentially habitable if the planet exhibits more than 50% cloud coverage. HD 85512 b is, with Gl 581 d, the best candidate for exploring habitability to date, a planet on the edge of habitability.

Well it is less strongly-irradiated than Venus, which is already a lot more promising than the vast majority of planets/planet candidates for which claims of habitability have been made...

What exactly is irradiation on this planet 90% of venus?80?someone knows?

Formula is L / ((a^2)*sqrt(1-e^2))

Where L is stellar luminosity, a is orbital semimajor axis and e is eccentricity.

If you use L in units of solar luminosity and a in AU you will get the ratio with respect to Earth (just about, the real Earth doesn't have exactly a=1 AU and e=0 but it is close enough for most purposes).

So you can plug in the numbers from the discovery paper and get the value.