Left: This simulation combines imagery from NASA’s Magellan and Pioneer missions and coloration from the Soviet Venera 13 and 14 spacecraft, revealing that Venus is currently a bone-dry planet. Right: Observations suggest that Venus may have had water oceans like these in its distant past, so NASA scientists used a climate model to explore a variety of land-sea and other configurations that could have made the planet habitable. Images by NASA/Jet Propulsion Laboratory-Caltech (left) and NASA (right). Credit: NASA

We have investigated the possible evolutional history of the water ocean on Venus, adopting the one dimensional radiative-convective model, including the parameters as albedo and relative humidity.

Under this model, it has the possibility that the habitable zone could include Venus. It could continue for ∼1 Gy in faint young solar flux increasing, with modest parameters such as albedo = 0.3, relative humidity (RH=1), and pn0=105Pa.

If we relax parameters considering the 3-Dimensional calculations, the ocean could exist there longer than ∼ 4.6 Gy. In such cases, we have to consider the cause of runaway other than just solar luminosity increasing. It is important to investigate Venus history for the coming future of Earth and observations of exoplanets for their historical habitable zones.

Tetsuya Hara, Anna Suzuki
Comments: 15pages,10 figures
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2009.04040 [astro-ph.EP] (or arXiv:2009.04040v1 [astro-ph.EP] for this version)
Submission history
From: Tetsuya Hara
[v1] Wed, 9 Sep 2020 00:05:46 UTC (1,279 KB)
https://arxiv.org/abs/2009.04040
Astrobiology

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp...