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

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.

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

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.

And we have confirmation of the second substellar object!

Asteroseismology of iota Draconis and Discovery of an Additional Long-Period Companion
https://arxiv.org/abs/2107.13583

Quote :

...We present the results of continued radial velocity monitoring of the star using the Automated Planet Finder over several orbits of the planet. We provide more precise planet parameters of the known planet and, through the combination of our radial velocity measurements with Hipparcos and Gaia astrometry, we discover an additional long-period companion with an orbital period of ~68+60−36 years. Mass predictions from our analysis place this sub-stellar companion on the border of the planet and brown dwarf regimes. The bright nature of the star combined with the revised orbital architecture of the system provides an opportunity to study planetary orbital dynamics that evolve as the star moves into the giant phase of its evolution.

They give us astrometric orbits for both planets!