NASA's Kepler finds planets, planets, planets

[LongTomH]

A press release from the NASA Kepler team announces the finding of over 1200 new planets. Before Kepler, about 500 exoplanets - planets outside our solar system - had been identified. Most were Jovian (Jupiter class) or larger (Superjovians, some orbiting very close to their parent stars: "hot Jupiters." Quoting from the NASA Kepler press release:

"We went from zero to 68 Earth-sized planet candidates and zero to {b]54 candidates in the habitable zone - a region where liquid water could exist on a planet’s surface. Some candidates could even have moons with liquid water," said William Borucki of NASA’s Ames Research Center, Moffett Field, Calif., and the Kepler Mission’s science principal investigator. "Five of the planetary candidates are both near Earth-size and orbit in the habitable zone of their parent stars."

Planet candidates require follow-up observations to verify they are actual planets.

"We have found over twelve hundred candidate planets - that’s more than all the people have found so far in history," said Borucki. "Now, these are candidates, but most of them, I’m convinced, will be confirmed as planets in the coming months and years."

Phil Plait has some comments on Kepler's discoveries on his Bad Astronomy blog, including an excellent discussion of Kepler's method of finding exoplanets:

Kepler detects planets by looking for the tell-tale dip in light as they pass in front of their star, and the amount of light blocked tells us the size of the planet. Kepler is staring at one part of the sky, continuously looking at 156,000 stars for these dips. After 23 months in orbit, it now has a passel of 1235 candidate planets. Of these, 68 are roughly Earth-sized, 288 are bigger than Earth, 662 are roughly Neptune-sized, 165 are Jupiter-like, and 19 are larger than Jupiter.

Phil discusses the possibility of planets with moons with liquid water - as mentioned in the NASA press release:

Also, I don’t want to dismiss the massive gas giants either. As we see with Jupiter and Saturn, big planets can have big moons. If Jupiter orbited the Sun where Earth is instead of five times as far out, its moon Europa wouldn’t be a frozen world, it would be an ocean world as big as our moon! Saturn’s moon Enceladus is also a frozen iceball, and would be a liquid waterworld if it were closer to the Sun. That artwork at the top, done by my friend and planetary scientist Dan Durda, might look fanciful to you, but what Kepler is showing us is that there very well may be moons with views like this. Maybe not with plants and birds and other life, but I’ll be honest: this is starting to look less like science fiction and more like science.

Here's the artwork Phil is referring to:



Note the Jupiter-size planet in the clouds. Yeah, this does look a lot like Pandora, the inhabited moon of a gas-giant planet in James Cameron's Avatar. There are more great images in Dan Durda's art gallery. Durda works with a 3d art program called Vue; it produces great landscape imagery.

What are the implications for SETI, the Search for Extra-Terrestrial Intelligence, of Kepler's findings? Back in the 1960s when SETI was just beginning, astronomer Frank Drake proposed what has come to the known as the Drake equation. Here it is in its original form:



N = the possible number of civilizations in the Milky Way galaxy we might be able to communicate with.

The terms of the equation equal:

• The average rate of star formation in the galaxy, times...
  
• The fraction of those stars that have planets, times....
  
• The average number of planets that can actually support life per star that has planets, times...
  
• The fraction of those planets that actually develop life at some point, times...
  
• The fraction of those planets with life that actually go on to develop intelligent life, times....
  
• The fraction of civilizations that go on to develop a technology that can release signs of the existence into space, times...
  
• The average length of time for which those civilizations are capable of sending signals.

With Kepler and the European Space Agencies COROT satellite we are starting to put numbers on the first three terms of the Drake equation.

Back to Phil Plait for some closing quotes:

During the Kepler press conference, planetary astronomer Debra Fischer called this "an incredible, historic moment." I agree! For years we’ve been making progress toward finding another blue-green world around another star, and this news means we’ve taken a really big stride in that direction.

For the first time in human history, we can look out into the night sky and actually and realistically and scientifically consider the presence of other Earths out there.

Science! I love this stuff.

Right on, Phil!

[nadinbrzezinski]

1. I love VUE, I have produced some stunning images on it

[yellowcanine]

2. The chances of there being extraterrestial life is huge, imo.

So called "intelligent life" ? It is an excellent question, but I tend to say it is likely as well.

[stuntcat]

3. chances are :)

yes!

(OH so finally I'm hopeful about something and it's not on this planet at all.. lol)

[LiberalFighter]

4. So many. Not enough time.

A Star Trek Enterprise is needed to make exploration feasible.

[Rex]

5. There is no doubt of other life out in space, to say otherwise is

foolish at best.