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ESI Values Out of date

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The Schulze-Makuch, Méndez et al. peer reviewed formula relies on an estimate of surface temperature, which is massively affected by atmospheric composition and greenhouse effects.

The Earth Similarity Index[1] page maintained by Abel Méndez at the University of Puerto Rico at Arecibo, lists both a simplified and peer-reviewed formula for the Earth Similarity Index. The disparity over Venus between 0.44 to 0.78 is related to use of the simplified (0.78) or peer-reviewed (0.44) formula.

I suggest the following standard basis to form the list:

  • Use the data from The Extrasolar Planets Encyclopaedia[2] which is the largest maintained exoplanet and exoplanet candidate catalog, including atmospheric constituents if known and enough information to guesstimate obscure but relevant things like the rotation rate of the host star and Stellar Soft X-ray (SXR) Luminosity.
  • Use the Schulze-Makuch, Méndez, et al. formula as written in the peer-reviewed paper. The ESI wiki article draws heavily upon the publish paper, and so it is the authoritative reference.
  • Failing sufficient atmospheric information, assume the Absorptivity (The fraction of the IR upwelling from surface that is absorbed within the atmosphere) is equivalent to Solar System siblings. For example, for planets massive enough to retain H2O in an atmosphere, and above the Komabayasi-Ingersoll Limit therefore susceptible to a runaway greenhouse effect then the absorptivity is 1.98 (like Venus). For planets massive enough and young enough to retain a magnetic field or otherwise likely has the protective benefit of a magnetic field with sufficient mass to retain an atmosphere against stellar wind and hydrodynamic loss then use an absorptivity of 0.8 (which covers Earth and Mars but also Saturn's Titan and Neptune's Triton. Otherwise for inner planets above the Komabayasi-Ingersoll Limit too small to otherwise retain H2O in an atmosphere assume 0.08 (like Mercury), and for all other terrestrial planets assume 1.6+/-0.4 (ie the dwarf planets and all other major moons).

The results will be identical for Solar system bodies as found in Schulze-Makuch et al. paper and quoted in a BBC article[3], however some of Schulze-Makuch et al. numbers for Venus like planets are likely different. Schulze-Makuch et al. does not appear to have accounted for Komabayasi-Ingersoll Limit or other atmospheric physics in their paper.

But this is all moot because of the above suggestion probably falls foul of the No-original-research policy. Failing someone writing a journal paper on ESI updating the values based on latest understand and more recent exoplanet discoveries then the only publicly and freely available consistent reference is the BBC article[3] list. Individual articles quoting an ESI for a single or small subset of planets/exoplanets is useless because of varying assumptions, varying ESI formula and inclusion or exclusion of various developments in atmosphere science.

Updated ESI Moon list to match Planet list

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I was thinking about moving the list of moons to the HabPlanetScore format for lists. I would like to know if its a go or no. (Yeah its a bit messy but the missing info will get filled in eventually).--User:Davidbuddy9 (talk) 16, January 2015

ESIs of non-planets

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The Moon, Io and Earth shown to scale. Although significantly smaller, some of the Solar System's moons and dwarf planets share similarities to Earth's density and temperature resulting in relatively high ESIs. It is theoretically possible for Earth-sized extrasolar moons and other non-planets to have high ESIs.

The ESI can be applied to objects other than planets, including natural satellites, dwarf planets and asteroids, though comparisons typically draw lower global ESI due to the lower average density and temperature of these objects, at least for those known in the Solar System.[4]

The following non-planetary objects have relatively high global ESIs:

# Name ESI SPH HZD HZC HZA pClass hClass Distance (ly) Status Year of
discovery
— Earth 1.00 0.72 -0.50 -0.31 -0.52 warm terran mesoplanet 0 non-exoplanet prehistoric
1 HD 222582 b m 0.86 ?? -0.75 ?? ?? warm subterran mesoplanet 136.8 Unconfirmed
2 Moon 0.559 ?? ?? ?? ?? warm? subterran? 0 non-exoplanet prehistoric
3 Io 0.362 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric
4 Callisto 0.338 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric
5 Ganymede 0.289 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric
6 Ceres 0.271 ?? ?? ?? ?? warm? asteroidan or subterran? 0 non-exoplanet prehistoric
7 Europa 0.262 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric
8 4 Vesta 0.256 ?? ?? ?? ?? warm? asteroidan 0 non-exoplanet prehistoric
9 Titan 0.242 ?? ?? ?? ?? warm? subterran? 0 non-exoplanet prehistoric
10 2 Pallas 0.222 ?? ?? ?? ?? warm? asteroidan 0 non-exoplanet prehistoric
11 Iapetus 0.211 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric
12 Titania 0.104 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric
13 Enceladus 0.094 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric
14 Pluto 0.094 ?? ?? ?? ?? cold? subterran or asteroidan? 0 non-exoplanet prehistoric
15 Triton 0.074 ?? ?? ?? ?? cold? subterran? 0 non-exoplanet prehistoric

Of these, only Titan is known to hold on to a significant atmosphere despite an overall lower size and density. --User:Davidbuddy9 (talk) 16, January 2015

References

  1. ^ "Earth Similarity Index (ESI)". Planetary Habitability Laboratory.
  2. ^ "The Extrasolar Planets Encyclopaedia". Paris Astronomical Data Center. {{cite web}}: line feed character in |title= at position 15 (help)
  3. ^ a b "Most liveable alien worlds ranked". BBC. November 23, 2011. Retrieved April 10, 2016.
  4. ^ pg 143. Multivariate and other worksheets for R (or S-Plus): a miscellany P.M.E.Altham, Statistical Laboratory, University of Cambridge. January 10, 2013

Intentional orphaning

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According to Tom.Reding, this is "Intentional orphaning" however, that is not a neutral description of what is going on. See WP:ONEWAY. jps (talk) 12:30, 22 April 2021 (UTC)[reply]

@ Talk:Earth analog#Removing see also, and possibly elsewhere more surreptitiously.   ~ Tom.Reding (talk ⋅dgaf)  03:22, 22 April 2021 (UTC)[reply]

Please stop personalizing things. If you think I have an "irrational bias" against ESI, we can discuss that elsewhere. But the fact of the matter remains that there is a severe lack of peer-reviewed sources about ESI. Shoehorning it into articles that have good sources none of which mention ESI is opposed to the editorial guidelines I've been outlining above. The way to demonstrate that ESI should be included is to present a reliable source which connects ESI to the article in question. In all the cases you outline, there was no citation to a reliable source and, in some cases, the citation was to a source that did not mention ESI at all! jps (talk) 14:37, 22 April 2021 (UTC)[reply]

Slow-mo edit conflict

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This preferred version by an IP is unsourced and has been removed for nearly a year. Seems to be no rationale for restoring it that I can find.

jps (talk) 19:14, 12 April 2022 (UTC)[reply]

Bonus points for this person threatening to report me for "removing [the table] that contains citations"... when all I did was fix phrasing that referenced the table that no longer was there. And they seem to be extremely passionate about this one single article. Is blocking them really not an option here? MinMinnH (talk) 16:49, 14 April 2022 (UTC)[reply]
It's a bit too "slow-mo" for it to be an option. If it escalates, we can take it to one of the relevant noticeboards. jps (talk) 17:40, 15 April 2022 (UTC)[reply]
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