8 replies to this topic

[Waspie_Dwarf]

Can astronomers detect exoplanet oceans?

phys.org said:

Detecting water on the surface of exoplanets is becoming a high priority for researchers, as surface water is considered a requirement for habitability. New research examines whether or not the "glint" of light from a planet can be interpreted as evidence for surface oceans.

Given the plethora of confirmed exoplanets, many researchers have turned their attention to studying these strange new worlds in greater detail. With several exoplanets thought to orbit in the “habitable zone” of their host star where liquid water might be stable, different methods of detecting surface water are under development. One such proposed method of detecting water oceans on an exoplanet is via specular reflection, also known as “glint”. If you've seen a bright reflection of sunlight on a lake or ocean here on Earth, you've seen an example of the glint effect.

Scientists posit that surface oceans of exoplanets would affect the planet’s apparent reflectivity, also known as albedo. This increase of albedo should be detectable during the crescent phase of a planet.

In this model, astronomers don’t need to see the entire “disk” of a planet, where the planet is reflecting light like a full Moon from our point of view. Instead, they can detect reflected starlight in a planet’s gibbous phase, where we see only a part of the entire “full Moon” light. It is even possible to view an exoplanet in a crescent phase, where just a small sliver of reflected light is visible.

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[Super-Fly]

Interesting, didnt they trial somesort of thing like this with the transit of venus,

or am i completely wrong?

Nice post OP!

[Waspie_Dwarf]

Super-Fly, on 15 July 2012 - 11:22 PM, said:

Interesting, didnt they trial somesort of thing like this with the transit of venus,

or am i completely wrong

Venus is just about the last planet you would use to help in the search for oceans. With a surface temperature of 480^oC, there's not a lot of liquid water there.

What astronomers were interested in with the transit of Venus was the planet's atmosphere. The hope is that the observations made will be able to help detect atmospheres on exoplanets when they transit their star.

[Super-Fly]

Waspie_Dwarf, on 15 July 2012 - 11:42 PM, said:

Venus is just about the last planet you would use to help in the search for oceans. With a surface temperature of 480^oC, there's not a lot of liquid water there.

What astronomers were interested in with the transit of Venus was the planet's atmosphere. The hope is that the observations made will be able to help detect atmospheres on exoplanets when they transit their star.

Ah right, my mistake, i knew they were interested in for looking for something, atmosphere.

Thanks for replying!

[marcos anthony toledo]

I would wait for a orbital observatory in deep space to search for oceans on exoplanets patance will win out in the end.

[Sundew]

While it would be scientifically interesting to find water or even oceans on other worlds, it is all rather academic to exploration/colonization. If a space vehicle cannot breach the speed of light barrier (and all thoughts are to how to do that are presently theoretical, certainly not practical) then these "water worlds" will always be tantalizingly out of reach. We are talking dozens or hundreds of light years distance, that is, if you COULD make a ship able to reach the speed of light, it would STILL take one or multiple generations of astronauts to reach these worlds. The effects of space short term are debilitating on the human body; cosmic radiation, lack of gravity causing loss of muscle and bone, mental and physical isolation, etcetera, so imagine a lifetime (or multiple lifetimes) of existence in space. Sci-fi to the contrary, we do not know how to put humans into hibernation for the long journey. Then you have to have enough energy/fuel to apply breaking to the ship, achieve orbit, reach the surface, AND then find a habitable world: The ocean might be caustic like a soda lake on earth, the atmosphere poisonous with methane or with too low and oxygen content or very high carbon dioxide levels, lifeforms, if they exist, might be incompatible with terrestrial organisms. We are not taking predatory xenomorphs of Alien fame; supposed you cannot eat the vegetation, or like War of the Worlds local microorganisms prove deadly or perhaps life there is composed of different amino acids? Also the theory of Relativity says that as you near the speed of light time to you seems to pass normally, but time on your place of origin would be racing into the future. I don't know the ratio, but if 20 years passes on your ship, hundreds, perhaps thousands of years pass on the earth, so you could never return to the world you left, the technological changes in that time would seem so great that it might as well be an unknown alien civilization to the ship's crew. And lastly, what if the world is inhabited? Our track record with our own species as we went about exploring the earth is not exactly stellar, ask the Apache, Hawaiian or the Aborigine. Would we be welcomed or seen as the alien invader, would our microorganisms wreck havoc on their population? But again for now we can look but not touch.

[Rhino666]

Why does it matter. We're not going there, it's too far.

Edited by Rhino666, 18 July 2012 - 06:50 PM.

[csspwns]

yea we should focus on mars a bit more

its closer and there is a big chance of water there

[St. Jimmy]

csspwns, on 19 July 2012 - 01:08 AM, said:

yea we should focus on mars a bit more

its closer and there is a big chance of water there

This is interesting. A picture of Mars how it may have looked a billion years ago.
http://xtremecoders..../Mars-Water.jpg
By the way, the chance of finding a liquid form of water isn't that big because of current conditions on the planet surface. But in the atmosphere is still small amount of water vapor.