Celestia Forums

HD 188753 Ab was claimed to be the first known exoplanet in a triple star system in 2005.

http://en.wikipedia.org/wiki/HD_188753_Ab
http://www.extrasolar.net/planettour.asp?PlanetID=305

Currently only the Primary Star (HD 188753 A) is represented in Celestia, so I've modified this star system in Celestia to add the two binary companion stars (HD 188753 B & C), the as yet disputed gas-giant, and a totally hypothetical moon.

I've had to make some assumptions/approximations/educated guesses with regard to some of the orbital elements, sizes etc. due to limited information available. I'm looking for volunteers to validate my assumptions to make sure they are at least plausible, or track down better information if it's available.

Anyone interested?

Artist impression:


and a couple of screen-caps from the Celestia version:

Triple Sunset from the surface of the moon:


Overview:


This world has apparently been nicknamed the "Tatooine Planet" in reference to the multiple suns of Luke Skywalker's homeworld in the movie "Star Wars", so I've taken the liberty of applying a "Tatooine" texture to the moon.

First off, HD 188753Ab is NOT the first exoplanet known in a triple system - that honour probably goes to 16 Cygni Bb.

Secondly, the planet probably doesn't exist. Eggenberger et al. (2007) "No evidence of a hot Jupiter around HD 188753 A". Having played around with the data for the system using the systemic console, I'd say the doubts over the planet's existence are quite well founded.

Thirdly, even if it did, tidal forces would have destroyed/destabilised large moons by now.

I have some elements for the HD 188753 system in this file, but its been a while since I last edited that file, and I failed to document the data sources for the orbits, which is bad.

HD 40979 is also tripple, as is HD 65216, and as ajtribick wrote, 16 Cygni as well.

Hello to the artist formerly known as chaos_syndrome ,

ajtribick wrote:First off, HD 188753Ab is NOT the first exoplanet known in a triple system - that honour probably goes to 16 Cygni Bb.

Maybe they meant "the first in a close orbiting short period triple system " ...(where tidal forces would be greater).

ajtribick wrote:Secondly, the planet probably doesn't exist. Eggenberger et al. (2007) "No evidence of a hot Jupiter around HD 188753 A". Having played around with the data for the system using the systemic console, I'd say the doubts over the planet's existence are quite well founded.

It's looking more and more like this is the case.

ajtribick wrote:Thirdly, even if it did, tidal forces would have destroyed/destabilised large moons by now.

If they even formed in the first place.

ajtribick wrote:I have some elements for the HD 188753 system in this file, but its been a while since I last edited that file, and I failed to document the data sources for the orbits, which is bad.

Thanks, here is: my version in it's current state - (also undocumented)
As you'll notice they are somewhat different. The sources of my information are rather dubious, and where I couldn't find any information (for example the elements of the BC orbits), I've just made it up. If you ever remember the source of your information I'd be interested to know.

Just for comparison purposes, here is: a modified version of your file which can be installed concurrently with mine, and locates your version in the same position as mine for easy visual comparison

And, if you're interested, here is: the fictional planet and moon (and getting more fictional by the hour).

CC

Chuft-Captain wrote:Hello to the artist formerly known as chaos_syndrome ,

...


CC

The new it's more Chaos again. It's the Syndrome.

Would anyone like to have a go at parsing Fenerit's first sentence there?

ajtribick wrote:Would anyone like to have a go at parsing Fenerit's first sentence there?

Found "ajtribick" more chaotic than "chaos_syndrome"...