User talk:EvenGreenerFish

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Welcome to Wikimedia Commons, EvenGreenerFish!

Re: Habitable zone diagram for solar system

[edit]

Thanks for the question!

In the description of the HD 85512 diagram I link to the paper on arXiv [1] which gives the formulae, it also tabulates the value for a 5700K G2 star. The Sun at 5780 K is somewhat hotter.

The incident fluxes in units of the solar flux at the Earth's orbit of the six habitable zone boundaries (three inner, three outer) are given by:

Limit Formula
Recent Venus
Runaway greenhouse
Water loss
CO2 cloud condensation
Maximum greenhouse
Early Mars

Note the above expressions are based on interpolating points at 3700 K (M0 star), 5700 K (G2 star) and 7200 K (F0 star) so are not valid outside this range.

The flux can then be converted to distance using:

Where distance d is in AU, luminosity L is in solar luminosities and the incident flux S is in units of the solar flux at Earth.

The tabulated and interpolated values are as follows:

Limit 5700 K (table) 5780 K (interpolated)
Flux Dist Flux Dist
Recent Venus 1.76 0.75 1.77 0.75
Runaway greenhouse 1.41 0.84 1.43 0.84
Water loss 1.10 0.95 1.11 0.95
CO2 cloud condensation 0.53 1.37 0.53 1.37
Maximum greenhouse 0.36 1.67 0.36 1.66
Early Mars 0.32 1.77 0.32 1.76

As you can see, moving from 5700 K to 5780 K does not make much difference!

Incidentally I would recommend you make the diagram as an SVG file rather than a PNG, this allows it to be scaled to any resolution and is ideal for diagrams. You can also put descriptive metadata into the files. Icalanise (talk) 21:00, 17 November 2012 (UTC)[reply]