Nine planets at HD 10180?

[ajtribick]

Evidence for 9 planets in the HD 10180 system

First system with more planets than our own, provided planets b, i and j are confirmed.

[Tegmine]

Very exciting, indeed.

-M-

[PlutonianEmpire]

why not
the star is a G1V type, 1.2 bigger and 1.56 brighter at more 128 LY.

That reminds me, why is it that all the G2V stars other than our sun, that I've seen, are significantly brighter and larger than our own sun, which itself would seem more like a G3V or G4V compared to the G2V's I've seen? (Or, vice versa: the other stars would be more like a F9V or G0V or G1V than a G2V compared to our sun?)

[Deepwatcher]

Thanks for sharing!

Now i want to code something for celestia about this system It should look great, 9 planets!
It is a pity we don't know the planetary radii... I will try to calculate them from an Astrophysical Journal publications, there's a lot of math behind the mass-radius relationship for planets

[kristoffer]

Possible a Super-Earth?, it is located in the "goldilock zone"
Or maybe it has some alien moons around it


planet f
Radius: 56000 km
Temperature: 296-339 K/23?C-66?C

[ajtribick]

Star has luminosity of 1.49 times solar. (See table 2 in this paper). To find the distance from the star where the planet receives as much radiation as Earth:

d / (1 AU) = sqrt(L / L*) = sqrt(1.49) = 1.2

So HZ is located at roughly 1.2 AU, close to the orbit of planet g.

Planet f at 0.49 AU receives 1.49 / (0.49^2) = 6.2 times as much radiation as the Earth does, which is comparable to Mercury (4.6 - 10.6 times the Earth's irradiation, variation due to the eccentric orbit).

[Tegmine]

I look forward to seeing how this add-on will turn out...

-M-

[Deepwatcher]

almost all data are at their place, soon i'll finish this ^^

I want to be as more physically accurate as possible. There truly is a LOT of math behind those planetary radii