MessageToEagle.com

Extrasolar Moons Are Considered To Be Habitable

14 January, 2013

Share this story:
Follow us:

MessageToEagle.com - Astronomers have started to consider exomoons, or those likely orbiting planets outside the solar system, as possible habitable worlds.

"The detection of moons orbiting extrasolar planets (“exomoons”) has now become feasible. Once discovered in the circumstellar habitable zone, questions about their habitability will emerge. Exomoons are likely to be tidally locked to their planet, and hence experience days much shorter than their orbital period around the star, and have seasons – all of which works in favor of habitability," astronomers explain in their paper.

The research, conducted by René Heller of Germany's Leibniz Institute for Astrophysics Potsdam and Rory Barnes of the University of Washington and the NASA Astrobiology Institute, will appear in the January issue of Astrobiology.



About 850 extrasolar planets — planets outside the solar system — are known, and most of them are sterile gas giants, similar to Jupiter. Only a few have a solid surface and orbit their host stars in the habitable zone, the circumstellar belt at the right distance to potentially allow liquid surface water and a benign environment.

Heller and Barnes tackled the theoretical question whether such planets could host habitable moons. No such exomoons have yet been discovered but there's no reason to assume they don't exist.

The climatic conditions expected on extrasolar moons will likely differ from those on extrasolar planets because moons are typically tidally locked to their planet.

Thus, similar to the Earth’s moon, one hemisphere permanently faces the planet.

Beyond that moons have two sources of light — that from the star and the planet they orbit — and are subject to eclipses that could significantly alter their climates, reducing stellar illumination.

„An observer standing on the surface of such an exomoon would experience day and night in a totally different way than we do on Earth.” explained Heller. “For instance stellar eclipses could lead to sudden total darkness at noon.”

Heller and Barnes also identified tidal heating as a criterion for exomoon habitability. This additional energy source is triggered by a moon’s distance to its host planet; the closer the moon, the stronger tidal heating. Moons that orbit their planet too closely will undergo strong tidal heating and thus a catastrophic runaway greenhouse effect that would boil away surface water and leave them forever uninhabitable.



Click on image to enlarge

Artist’s conception of two extrasolar moons orbiting a giant gaseous planet. (Credits: R. Heller, AIP)


They also devised a theoretical model to estimate the minimum distance a moon could be from its host planet and still allow habitability, which they call the "habitable edge."This concept will allow future astronomers to evaluate the habitability of extrasolar moons.

"There is a habitable zone for exomoons, it's just a little different than the habitable zone for exoplanets," Barnes said.

MessageToEagle.com

See also:
Galaxy Clusters May Offer Critical Clues To Dark Energy

Follow MessageToEagle.com for the latest news on Facebook and Twitter !

Don't Miss Our Stories! Get Our Daily Email Newsletter

Enter your email address:


Once you have confirmed your email address, you will be subscribed to the newsletter.

Recommend this article:

Teleportation Experiments Continue - Record-Breaking Distance of 143 Kilometers Achieved!

Violent Behavior Of Our Sun - Massive 500,000 Mile Long Filament Observed

First Massive Galaxies Lit Up The Early Universe

Intense Blue Lightning On Saturn Visible From Space In Broad Daylight!

Subscribe To Our Space, Astronomy, Astrophysics, Earth and Xenology News!

Grab the latest RSS feeds right to your reader, desktop or mobile phone.

Subscribe to RSS headline updates from:
Powered by FeedBurner

Go to - MAIN PAGE

Copyright © MessageToEagle.com All rights reserved.
Go to - MAIN PAGE


Get our top stories
Follow MessageToEagle.com

 Subscribe in a reader

Join Us On Facebook!

Other Popular Articles

Universe:


Astronomers Capture Extraordinary View Of Radio Galaxy Hercules A

Uncovering Secrets Of Impenetrable Alien World

"Star Nursery" In The Constellation Taurus Where Lower Mass Stars Are Born

Is There Too Much Dark Matter In Galaxy Cluster Abell 520?

MESSENGER Spacecraft Delivers New Evidence For Water Ice at Mercury's Poles

The Beginning Of Everything: A New Paradigm Shift For The Infant Universe

Discovery Of Growing Rocky Planets Around Brown Dwarf Surprise Astronomers

Spectacular New Images Of Saturn's Swirling Storms

Mysterious, Huge 'Pigtail' Molecular Cloud Discovered In The Galactic Center

Astronomers See The Infant Universe's Oldest Galaxies Yet!

Star With The Secret Of Eternal Youth

Physicists Challenge Validity Of Big Bang Theory

Space-Time Crystal Computer That Can Outlive Even The Universe Itself!

Dawn Spacecraft Is Heading Towards Dwarf Planet Ceres To Investigate The Formation Of Our Solar System

New Photos Of Saturn And Its Moon Titan - See A Striking Change Of Colors!

What’s Going On Out There? - NASA's RBSP Spacecraft Will Meet ‘Killer Electrons’ And Other Dangerous Phenomena

Mysterious X-Rays From Jupiter Near The Poles

Eyes on Mars:


NASA Scientists Are Monitoring Regional Martian Dust Storm

Martian Environments Capable Of Supporting Life - Similar To Ours

Red Planet Once Had Hot Water

Methane Found In Previous Rover Missions To Mars - Curiosity Finds No Methane Yet

Curiosity Continues With Scoops At 'Rocknest'

Once Upon A Time There Was Water On Mars - Scientists Say

Futurism:


Star Trek Universal Translator Available!


A Look Into The Future: Can Planet Earth Support 10 Billion People?

Is This What Humans Will Look Like In Millions Of Years From Now?

W3Counter