Exoplanets plugin

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==Description==
 
==Description==
This plugin plots the position of stars with exoplanets. Exoplanets data is derived from "[http://exoplanet.eu/ The Extrasolar Planets Encyclopaedia]"
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This plugin plots the position of stars with exoplanets. Exoplanets data is derived from "[http://exoplanet.eu/ The Extrasolar Planets Encyclopaedia]". List of potential habitable exoplanets and data about them were taken from "The Habitable Exoplanets Catalog" by Planetary Habitability Laboratory.
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Example (HD 13808):
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http://stellarium.org/wikiimg/exoplanets/exoplanets.jpg
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===Potential habitable exoplanets===
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Since version 0.1.12 (Stellarium 0.13.0) this plugin can display potential habitable exoplanets (orange marker) and some information about those planets - habitable class, mean surface temperature and Earth Similarity Index.
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* '''Habitable Class''' — Classifies habitable planets based on temperature: hypopsychroplanets (O or hP) = very cold (less −50°C); psychroplanets (P) = cold; mesoplanets (M) = medium-temperature (0–50°C); thermoplanets (T) = hot; hyperthermoplanets (E or hT) = very hot (above 100°C). Mesoplanets would be ideal for complex life, whereas class O or E would only support extremophilic life. Non-habitable planets are simply given the class X (or NH).
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* '''Mean Surface Temperature''' — Temperature in (°C) based on a similar terrestrial atmosphere to planet mass ratio and a greenhouse effect due to 1 percent of CO2 (assuming an albedo of 0.3 in all cases).
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* '''Earth Similarity Index (ESI)''' — Similarity to Earth on a scale from 0 to 1, with 1 being the most Earth-like. ESI depends on the planet's radius, density, escape velocity, and surface temperature.
  
 
==Using the Exoplanets plugin==
 
==Using the Exoplanets plugin==
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"angleDistance": angle distance from star (arcseconds),
 
"angleDistance": angle distance from star (arcseconds),
 
"discovered": exoplanet discovered year,
 
"discovered": exoplanet discovered year,
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"hclass": "habitable class",
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"MSTemp": mean surface temperature (K),
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"ESI": Earth Similarity Index (*100),
 
"planetName": "designation of planet"
 
"planetName": "designation of planet"
 
},
 
},
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"angleDistance": angle distance from star (arcseconds),
 
"angleDistance": angle distance from star (arcseconds),
 
"discovered": exoplanet discovered year,
 
"discovered": exoplanet discovered year,
 +
"hclass": "habitable class",
 +
"MSTemp": mean surface temperature (K),
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"ESI": Earth Similarity Index (*100),
 
"planetName": "designation of planet"
 
"planetName": "designation of planet"
 
}
 
}
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"sradius": value of radius of star (R sun),
 
"sradius": value of radius of star (R sun),
 
"effectiveTemp": value of effective temperature of star (K),
 
"effectiveTemp": value of effective temperature of star (K),
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"hasHP": boolean (has potential habitable planets),
 
"RA": "Right ascension (J2000)",
 
"RA": "Right ascension (J2000)",
 
"DE": "Declination (J2000)"
 
"DE": "Declination (J2000)"
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  | 1
 
  | 1
 
  | Updated code.  
 
  | Updated code.  
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|-
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| 0.1.12
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| 0.13.0
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| 1
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| Display potential habitable planets.
 
  |}
 
  |}
  

Revision as of 17:20, 4 October 2013

Contents

Description

This plugin plots the position of stars with exoplanets. Exoplanets data is derived from "The Extrasolar Planets Encyclopaedia". List of potential habitable exoplanets and data about them were taken from "The Habitable Exoplanets Catalog" by Planetary Habitability Laboratory.

Example (HD 13808):

exoplanets.jpg

Potential habitable exoplanets

Since version 0.1.12 (Stellarium 0.13.0) this plugin can display potential habitable exoplanets (orange marker) and some information about those planets - habitable class, mean surface temperature and Earth Similarity Index.

  • Habitable Class — Classifies habitable planets based on temperature: hypopsychroplanets (O or hP) = very cold (less −50°C); psychroplanets (P) = cold; mesoplanets (M) = medium-temperature (0–50°C); thermoplanets (T) = hot; hyperthermoplanets (E or hT) = very hot (above 100°C). Mesoplanets would be ideal for complex life, whereas class O or E would only support extremophilic life. Non-habitable planets are simply given the class X (or NH).
  • Mean Surface Temperature — Temperature in (°C) based on a similar terrestrial atmosphere to planet mass ratio and a greenhouse effect due to 1 percent of CO2 (assuming an albedo of 0.3 in all cases).
  • Earth Similarity Index (ESI) — Similarity to Earth on a scale from 0 to 1, with 1 being the most Earth-like. ESI depends on the planet's radius, density, escape velocity, and surface temperature.

Using the Exoplanets plugin

  1. Enable the tool by clicking the tool-bar button "Load at startup"
  2. Find the stars with exoplanets by their designation (24 Sex as example)

Catalog of stars with exoplanets

You can modify the exoplanets.json file manually using a text editor. If you are using Windows, it is strongly recommended to use an advanced text editor such as Notepad++ to avoid problems with end-of-line characters. (It will also color the JSON code and make it easier to read.)

Warning: Before editing your JSON file, make a backup copy. Leaving out the smallest detail (such as a comma or forgetting to close a curly bracket) will prevent Stellarium from starting.

The path to the directory which contains exoplanets.json is something like:

  • C:\Users\UserName\AppData\Roaming\Stellarium\modules\Exoplanets (Windows Vista, Windows 7)
  • C:\Documents and Settings\UserName\Application Data\Stellarium\modules\Exoplanets (Windows XP)
  • HomeDirectory/Library/Preferences/Stellarium/modules/Exoplanets (Mac OS X)
  • ~/.stellarium/modules/Exoplanets (Linux)

(Note that this is a hidden folder, so in order to find it you may need to change your computer's settings to display hidden files and folders.)

Format of catalog

To add a new star with exoplanets, open a new line after line 5 and paste the following, note commas and brackets, they are important:

                "Star designation":
		{
			"exoplanets":
			[
			{
				"mass": mass of exoplanet (M jup),
				"radius": radius of exoplanet (R jup),
				"period": period of exoplanet (days),
				"semiAxis": semi-major axis (AU),
				"eccentricity": orbit's eccentricity,
				"inclination": orbit's inclination (degree),
				"angleDistance": angle distance from star (arcseconds),
				"discovered": exoplanet discovered year,
				"hclass": "habitable class",
				"MSTemp": mean surface temperature (K),
				"ESI": Earth Similarity Index (*100),
				"planetName": "designation of planet"
			},
			{
				"mass": mass of exoplanet (M jup),
				"radius": radius of exoplanet (R jup),
				"period": period of exoplanet (days),
				"semiAxis": semi-major axis (AU),
				"eccentricity": orbit's eccentricity,
				"inclination": orbit's inclination (degree),
				"angleDistance": angle distance from star (arcseconds),
				"discovered": exoplanet discovered year,
				"hclass": "habitable class",
				"MSTemp": mean surface temperature (K),
				"ESI": Earth Similarity Index (*100),
				"planetName": "designation of planet"
			}
			],
			"distance": value of distance to star (pc),
			"stype": "spectral type of star",
			"smass": value of mass of star (M sun),
			"smetal": value of metallicity of star,
			"Vmag": value of visual magnitude of star,
			"sradius": value of radius of star (R sun),
			"effectiveTemp": value of effective temperature of star (K),
			"hasHP": boolean (has potential habitable planets),
			"RA": "Right ascension (J2000)",
			"DE": "Declination (J2000)"
		},

For example, record for 24 Sex:

                "24 Sex":
		{
			"exoplanets":
			[
			{
				"mass": 1.99,
				"period": 452.8,
				"semiAxis": 1.333,
				"eccentricity": 0.09,
				"angleDistance": 0.017821,
				"discovered": 2010,
				"planetName": "b"
			},
			{
				"mass": 0.86,
				"period": 883.0,
				"semiAxis": 2.08,
				"eccentricity": 0.29,
				"angleDistance": 0.027807,
				"discovered": 2010,
				"planetName": "c"
			}
			],
			"distance": 74.8,
			"stype": "G5",
			"smass": 1.54,
			"smetal": -0.03,
			"Vmag": 7.38,
			"sradius": 4.9,
			"effectiveTemp": 5098,
			"RA": "10h23m28s",
			"DE": "-00d54m08s"
		},

Version history

Plug-in version Stellarium version Catalog version Significant changes
0.1.2 0.11.4 1 First public version of plugin
0.1.4 0.12.0 1 Use new rendering engine of core; Distribution mode; Timeline mode
0.1.5 0.12.1 1 Display the detection method of exoplanet
0.1.10 0.12.2 1 Improvements for search tool. Updated code. Improvements for GUI.
0.1.11 0.12.3 1 Updated code.
0.1.12 0.13.0 1 Display potential habitable planets.

Acknowledgment

We thank the following people for their contribution and of the valuable comments:

  • Jean Schneider (Maintainer of "The Extrasolar Planets Encyclopaedia" who grant permission us use its catalog).
  • Oscar Roig Felius, who finding mistakes into catalog of exoplanets.

How you can help

We are welcome bug reports, feature requests and feedback through the usual channels (trackers, forums and so on).

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