Is Gliese 581d a Habitable Super-Earth?

  • Thread starter Thread starter marcus
  • Start date Start date
AI Thread Summary
The study investigates the habitability of super-Earths in the Gliese 581 system, focusing on Gl 581d, which is located near the outer edge of the habitable zone. Using a thermal evolution model, researchers estimate that Gl 581d, being several times the mass of Earth, likely retains a substantial atmosphere and has a surface pressure at least five times that of Earth. Despite being tidally locked, the greenhouse effect may allow for conditions suitable for liquid water. In contrast, Gl 581c is deemed uninhabitable due to its proximity to the star. The findings provide insights into how future Earth-mass exoplanets may be assessed for potential habitability.
marcus
Science Advisor
Homework Helper
Gold Member
Dearly Missed
Messages
24,753
Reaction score
794
http://arxiv.org/abs/0705.3758

The habitability of super-Earths in Gliese 581
W. von Bloh, C. Bounama, M. Cunntz, S. Franck
4 pages, 2 figures, 1 table
(Submitted on 25 May 2007)

"Aims: The planetary system around the M star Gliese 581 consists of a hot Neptune (Gl 581b) and two super-Earths (Gl 581c and Gl 581d). The habitability of this system with respect to the super-Earths is investigated following a concept that studies the long-term possibility of photosynthetic biomass production on a dynamically active planet. Methods: A thermal evolution model for a super-Earth is used to calculate the sources and sinks of atmospheric carbon dioxide. The habitable zone is determined by the limits of biological productivity on the planetary surface. Models with different ratios of land / ocean coverage are investigated. Results: The super-Earth Gl 581c is clearly outside the habitable zone, since it is too close to the star. In contrast, Gl 581d is a tidally locked habitable super-Earth near the outer edge of the habitable zone. Despite the adverse conditions on this planet, at least some primitive forms of life may be able to exist on its surface."

this study attempted to estimate most probable conditions on Gliese581D
which is near the outer border of habitable for the dim reddish primary

Because of the planets large mass, several times Earth mass, they judged that it would contain a lot of volatiles and would hold its atmosphere
so they estimated a surface atm. pressure at least 5X Earth normal.

the planet is INSIDE the tidal locking radius for the system so it would keep one face always to the primary ("sun")

figuring in the greenhouse effect, they decided it would not be too cold for liquid water.

I found their analysis interesting and informative, suggesting how earth-mass planets discovered in the future may be analyzed for habitability.
 
Last edited:
TL;DR Summary: In 3 years, the Square Kilometre Array (SKA) telescope (or rather, a system of telescopes) should be put into operation. In case of failure to detect alien signals, it will further expand the radius of the so-called silence (or rather, radio silence) of the Universe. Is there any sense in this or is blissful ignorance better? In 3 years, the Square Kilometre Array (SKA) telescope (or rather, a system of telescopes) should be put into operation. In case of failure to detect...
Thread 'Could gamma-ray bursts have an intragalactic origin?'
This is indirectly evidenced by a map of the distribution of gamma-ray bursts in the night sky, made in the form of an elongated globe. And also the weakening of gamma radiation by the disk and the center of the Milky Way, which leads to anisotropy in the possibilities of observing gamma-ray bursts. My line of reasoning is as follows: 1. Gamma radiation should be absorbed to some extent by dust and other components of the interstellar medium. As a result, with an extragalactic origin, fewer...
This thread is dedicated to the beauty and awesomeness of our Universe. If you feel like it, please share video clips and photos (or nice animations) of space and objects in space in this thread. Your posts, clips and photos may by all means include scientific information; that does not make it less beautiful to me (n.b. the posts must of course comply with the PF guidelines, i.e. regarding science, only mainstream science is allowed, fringe/pseudoscience is not allowed). n.b. I start this...
Back
Top