The truth about exoplanets

Nature ^ | 17 Feb, 2016 | Jeff Hecht

[MtnClimber]

Astronomers are beginning to glimpse what exoplanets orbiting distant suns are actually like. The trickle of discoveries has become a torrent. Little more than two decades after the first planets were found orbiting other stars, improved instruments on the ground and in space have sent the count soaring: it is now past 2,000. The finds include 'hot Jupiters', 'super-Earths' and other bodies with no counterpart in our Solar System - and have forced astronomers to radically rethink their theories of how planetary systems form and evolve. Yet discovery is just the beginning. Astronomers are aggressively moving into a crucial phase in exoplanet research: finding out what these worlds are like. Most exoplanet-finding techniques reveal very little apart from the planet's mass, size and orbit. But is it rocky like Earth or a gas giant like Jupiter? Is it blisteringly hot or in deep-freeze? What is its atmosphere made of? And does that atmosphere contain molecules such as water, methane and oxygen in odd, unstable proportions that might be a signature of life? The only reliable tool that astronomers can use to tackle such questions is spectroscopy: a technique that analyses the wavelengths of light coming directly from a planet's surface, or passing through its atmosphere. Each element or molecule produces a characteristic pattern of 'lines' - spikes of light emission or dips of absorption at known wavelengths - so observers can look at a distant object's spectrum to read off what substances are present. "Without spectroscopy, you are to some extent guessing what you see," says Ian Crossfield, an astronomer at the University of Arizona in Tucson.

[MtnClimber]

A really interesting article. I was able to post only a short section.

[txnativegop]

thanks for posting this. This is very interesting.

[MtnClimber]

Thanks. Seems satellites and high-elevation telescopes will be focusing on this. What I wonder about is how they will differentiate stars with multiple planets and planets with long orbital times.

u

[txnativegop]

I think they are still trying to figure that particular problem out, imo.

[Ciexyz]

Interesting.

[GraceG]

Quick! If you find one I will work on my warp drive and we can escape the insanity of this planet we are currently stuck on!

[Prospero]

Interesting summary of a vast topic, and a great argument for planting a basin sized telescope on the Moon's farside, which will be directly under the Legrange point where they plan to "park" the long, long planned JWST...

thanks, much.

[samtheman]

I prefer the lunar South Pole.

In a crater, in perpetual shadow.

Pointed at the center of the Galaxy.

Serviced by an army of robots.

Manned by astronomers.

Visited by tourists.

[WhiskeyX]

The next big leap will be the discovery of rogue planets traveling through interstellar space without a companion star/s.

[SunkenCiv]

same talking points:

Exoplanet Census Suggests Earth Is Special after All
http://www.freerepublic.com/focus/chat/3399474/posts

[txnativegop]

The History Channel show “The Universe” had an episode in which several of the scientists on the show claimed that TEN such planets had already been found.

[SunkenCiv]

• Copernicus and the made-up planets: simulating other earths
• Exoplanet Census Suggests Earth Is Special after All
• Wild new theory says Earth may actually be two different planets

· join · view topics · view or post blog · bookmark · post new topic · subscribe ·

Google news searches: exoplanet · exosolar · extrasolar ·

[mowowie]

I would imagine there a millions of dark solar systems out there.

[TomasUSMC]

Seems like NASA will be making an annoucement today about exoplanets?

[cynwoody]

Visited by tourists.

When they get sick of visiting Jurassic parks and get a bonus or hit a payday on the market.