Extrasolar Planets (updated catalogue)
Posted: 26.03.2019, 23:59
I have created some files for an updated extrasolar planets catalogue. I will be updating it as discoveries are made. It contains the following files:
> One .ssc file for the confirmed planets.
> One .ssc file for the unconfirmed planets.
> One .stc file for the star systems with confirmed planets.
> One .stc file for the star systems without confirmed planets.
> Several scripts to mark planets by discovery method, or by TESS/Kepler/Kepler-K2.
Download link to most recent version (01 September 2024):
viewtopic.php?p=162743#p162743
The information contained below is outdated, but it is left for historical reasons. This project has evolved and improved considerably in the years since it started.
The orbits of the planets are converted from using the reference plane of the sky to Celestia's internal reference plane through the formulae given in Grant Hutchison's starorbs.xls. spread sheet. For systems with a combination of transiting and non-transiting planets, the non-transiting planet was given an inclination equal to the transiting planet, plus five degrees. I may change this logic later to only do so if having the same inclination produces an orbit with an impact parameter of b < 1. Some circumbinary planets do not have known inclinations, yet their hosts are eclipsing binary stars. For most of them, I have simply not defined the stellar hosts as an eclipsing binary system (the system is thus coplanar with the planet), though for non-transiting Kepler circumbinary planets, they are rendered as eclipsing binaries but non-coplanar with the planet orbit (whose inclination is not declared). I may normalize this in the future. (Fixed!)
Otherwise, for planets with orbit inclinations determined astrometrically, only the planet with a measure inclination has been modified to reflect that. This makes some systems look atrocious (EPS Eri, GJ 676 A). I may rework the logic on this as well to assume system coplanarity. This will become very important as Gaia reveals intermediate-period planets around stars with already-known close-in RV planets. (Fixed!)
There are many extrasolar planets in multi-stellar systems. For systems where the components have known masses and separations, a simple binary stellar orbit was constructed for it, though I acknowledge that for some systems, it may place stellar components at incorrect position angles and separations. For multi-stellar systems where I could not find the mass ratios or separations, yet RA and Dec coordinates are available for the secondary component(s), I simply defined the two stars separately as nearby single stars. For multi-stellar systems where I could not find enough information to do either, I simply declared the host star as a single star. In all cases, the stars are given 'A', 'B', etc in their identifier.
The microlensing systems still need work. (Fixed!)
Often, especially for Kepler-# and KOI-# stars, spectral types are not known. If this is the case, I estimated the spectral type from the star's effective temperature according to the relation given by Eric Mamajek here.
Planets with masses above 3000 Earth-masses are assigned a brown dwarf texture. This is true even the planet's mass is known only as an upper limit. There's a few cases where this is particularly bad, such as at Kepler-453,Kepler-27, when clearly sub-Jovian planets are represented as brown dwarfs. This will be fixed in the next update. (Fixed!)
Star distances where possible have been determined from Gaia DR2 parallaxes. AppMag values (V magnitudes) are not known for quite a few stars. In such cases, they have been estimated from the 2MASS JHK fluxes. For stars where parallaxes or distances are unknown, neither the star nor its planetary system are included in this add-on. This is limited to just a few KOI systems whose planets are unconfirmed anyway, so it shouldn't be particularly obvious.
Finally, this add-on is intended to represent as complete an exoplanet catalogue as possible. You must remove both the extrasolar.ssc and extrasolar.stc files from your data folder, otherwise you will have duplicate planet definitions.
I'm open to any ideas for improvement that fit the spirit of representing the extrasolar planets in a scientifically accurate way, within the constraints of what is known.
Download Link here (01 Aug 2019)
> One .ssc file for the confirmed planets.
> One .ssc file for the unconfirmed planets.
> One .stc file for the star systems with confirmed planets.
> One .stc file for the star systems without confirmed planets.
> Several scripts to mark planets by discovery method, or by TESS/Kepler/Kepler-K2.
Download link to most recent version (01 September 2024):
viewtopic.php?p=162743#p162743
The information contained below is outdated, but it is left for historical reasons. This project has evolved and improved considerably in the years since it started.
The orbits of the planets are converted from using the reference plane of the sky to Celestia's internal reference plane through the formulae given in Grant Hutchison's starorbs.xls. spread sheet. For systems with a combination of transiting and non-transiting planets, the non-transiting planet was given an inclination equal to the transiting planet, plus five degrees. I may change this logic later to only do so if having the same inclination produces an orbit with an impact parameter of b < 1. Some circumbinary planets do not have known inclinations, yet their hosts are eclipsing binary stars. For most of them, I have simply not defined the stellar hosts as an eclipsing binary system (the system is thus coplanar with the planet), though for non-transiting Kepler circumbinary planets, they are rendered as eclipsing binaries but non-coplanar with the planet orbit (whose inclination is not declared). I may normalize this in the future. (Fixed!)
Otherwise, for planets with orbit inclinations determined astrometrically, only the planet with a measure inclination has been modified to reflect that. This makes some systems look atrocious (EPS Eri, GJ 676 A). I may rework the logic on this as well to assume system coplanarity. This will become very important as Gaia reveals intermediate-period planets around stars with already-known close-in RV planets. (Fixed!)
There are many extrasolar planets in multi-stellar systems. For systems where the components have known masses and separations, a simple binary stellar orbit was constructed for it, though I acknowledge that for some systems, it may place stellar components at incorrect position angles and separations. For multi-stellar systems where I could not find the mass ratios or separations, yet RA and Dec coordinates are available for the secondary component(s), I simply defined the two stars separately as nearby single stars. For multi-stellar systems where I could not find enough information to do either, I simply declared the host star as a single star. In all cases, the stars are given 'A', 'B', etc in their identifier.
The microlensing systems still need work. (Fixed!)
Often, especially for Kepler-# and KOI-# stars, spectral types are not known. If this is the case, I estimated the spectral type from the star's effective temperature according to the relation given by Eric Mamajek here.
Planets with masses above 3000 Earth-masses are assigned a brown dwarf texture. This is true even the planet's mass is known only as an upper limit. There's a few cases where this is particularly bad, such as at Kepler-453,Kepler-27, when clearly sub-Jovian planets are represented as brown dwarfs. This will be fixed in the next update. (Fixed!)
Star distances where possible have been determined from Gaia DR2 parallaxes. AppMag values (V magnitudes) are not known for quite a few stars. In such cases, they have been estimated from the 2MASS JHK fluxes. For stars where parallaxes or distances are unknown, neither the star nor its planetary system are included in this add-on. This is limited to just a few KOI systems whose planets are unconfirmed anyway, so it shouldn't be particularly obvious.
Finally, this add-on is intended to represent as complete an exoplanet catalogue as possible. You must remove both the extrasolar.ssc and extrasolar.stc files from your data folder, otherwise you will have duplicate planet definitions.
I'm open to any ideas for improvement that fit the spirit of representing the extrasolar planets in a scientifically accurate way, within the constraints of what is known.
Download Link here (01 Aug 2019)