# Evidence for 2nd planet at Iota Draconis

## Evidence for 2nd planet at Iota Draconis

The Discovery of Stellar Oscillations in the K Giant $\iota$ Dra
http://arxiv.org/abs/0809.4857

Abstract wrote:$\iota$ Dra (HIP 75458) is a well-known example for a K giant hosting a substellar companion since its discovery by Frink et al. (2002). We present radial velocity measurements of this star from observations taken with three different instruments spanning nearly 8 years. They show more clearly that the RV period is long-lived and coherent thus supporting the companion hypothesis. The longer time baseline now allows for a more accurate determination of the orbit with a revised period of P=511 d and an additional small linear trend, indicative of another companion in a wide orbit. Moreover we show that the star exhibits low amplitude, solar like oscillations with frequencies around 3-4 d$^{-1}$ (34.7-46.3 $\mu$Hz).

Edasich should like this one...

It seems that Iot Dra b is a bit heftier than thought, m sin i ~10.3 M_jup

_________________
Caps Lock: Cruise control for 'Cool'!

Sirius_Alpha

Number of posts : 3468
Location : Earth
Registration date : 2008-04-06

## Re: Evidence for 2nd planet at Iota Draconis

Sirius_Alpha wrote:It seems that Iot Dra b is a bit heftier than thought, m sin i ~10.3 M_jup
This seems to be a result of the different mass used for Iota Draconis itself... this paper uses 1.4 solar masses, while previously a lower mass of 1.05 solar masses was used.

Lazarus
dG star

Number of posts : 2819
Registration date : 2008-06-12

## Re: Evidence for 2nd planet at Iota Draconis

I was sure I had to host another planet around... myself ... *LOL*

Edasich
dM star

Number of posts : 1510
Location : Tau Ceti g - Mid Latitudes
Registration date : 2008-06-02

## Re: Evidence for 2nd planet at Iota Draconis

Lazarus wrote:
Sirius_Alpha wrote:It seems that Iot Dra b is a bit heftier than thought, m sin i ~10.3 M_jup
This seems to be a result of the different mass used for Iota Draconis itself... this paper uses 1.4 solar masses, while previously a lower mass of 1.05 solar masses was used.

Indeed, and according to this paper, the mass of Iot Dra may actually be a little over 2 solar masses, but these results are preliminary. If so, I think that may be enough to tip Iot Dra b over the 13 Jupiter-mass limit.

_________________
Caps Lock: Cruise control for 'Cool'!

Sirius_Alpha

Number of posts : 3468
Location : Earth
Registration date : 2008-04-06