HD 34445: Six Giant Planets around a Sun-Like Star

[ProtoJeb21]

Thanks to the amazing work done by Vogt et al., there is a new six-planet system! HD 34445 is a large G-type star of 1.38 R_Sun and 1.07 M_Sun with twice our Sun's luminosity and a high metallicity of +0.14 [Fe/H]. Back in 2009, a gas giant of 0.79 Jupiter masses orbiting in an eccentric (e=0.27) orbit at 2.07 AU was found. Now, after analysis of 19 years worth of radial velocity data, Steve Vogt and his team have found five more gas and ice giants, with orbital periods between a few weeks and a decade. All six worlds are 16.8, 30.7, 53.5, 37.9, 250.0, and 120.6 times the mass of Earth and orbit every 49.18, 117.87, 214.67, 676.8, 1,049.0, and 5,700.0 days. Two are in the system's habitable zone and could have potentially life-friendly moons. This is an absolutely amazing find, as it not only shows that spaced-out systems with multiple planets around Sun-like stars do exist, but that they can be fundamentally similar and different to our own Solar System. Planetary systems like HD 10180 and Tau Ceti are also great examples, the latter of which is rather similarly structured to our own inner system.

Data for the system on NASA's Exoplanet Archive: https://exoplanetarchive.ipac.caltech.edu/cgi-bin/DisplayOverview/nph-DisplayOverview?objname=HD+34445&type=PLANET_HOST

Vogt et al's paper on the system: https://arxiv.org/pdf/1710.07337.pdf

[Scotius]

So, all-gas-giants system Another weird member of the planetary menagerie. I wonder if any rocky planets managed to fully form there. Did they crash into giants during their migrations? Got ejected? Or maybe captured as moons.

[ILoveStars]

nice i know aboiut it

 

[Ozymandias_the_Goat]

On 10/29/2017 at 4:00 AM, Scotius said:

So, all-gas-giants system Another weird member of the planetary menagerie. I wonder if any rocky planets managed to fully form there. Did they crash into giants during their migrations? Got ejected? Or maybe captured as moons.

It is possible that they exist, but simply cannot be detected by the Doppler method. To be fair, if aliens of s singular technology level as us observed the Solar System, they very well may determine that it is a system of 4 gas giants. 

In the case of this system, this is a bit less likely, as some of these large planets are actually in the habitable zone, one of them being much closer, and since we all know that smaller planets do not typically form around gas giants, it is likely that they never formed at all, or did become moons. 

Nevertheless, it is a landmark find, which will no doubt vindicate every single elementary school science teacher who told us that that sun is an “average sized star”.

Wait a sec I just realized that this thread is years old.

[ILoveStars]

i used to think there were rocky planets in this system

[kerbiloid]

The longer, the more the world looks like Elite.

Spoiler