Kepler gets it done

Check the newspapers today about finding more earth-size planets.

I'm finding by watching some of the programs now just how much more than I realized all the space exploration, including telescope, has increased our knowledge of the universe. And even astronomers didn't necessarily predict this not so long ago; for example many had wondered if we would *ever* be able to spot planets around other stars unless it proved possible to do deep space travel. Yet the way it is done now seems so simple, as the below shows. But it has proved to be the case that the Kepler gets the essential job done, which perhaps had been in doubt. Image from wsj.com.

Except for one thing...

Many of those calculations rely upon the planet passing between the star and the Kepler telescope. I.E. Kepler needs to be on the planet's orbital plane.

Any planet on a different orbital plane will be missed.

Quote: odiousgambit

And even astronomers didn't necessarily predict this not so long ago; for example many had wondered if we would *ever* be able to spot planets around other stars unless it proved possible to do deep space travel. Yet the way it is done now seems so simple, as the below shows.

Back in the 80s in his show and book "Cosmos," Carl Sagan explained and demonstrated various techniques for detecting planets around other stars. Naturally I ws left wondering why if astronomers knew how to find them, none had been found. Obviously, and with indsight, better instruments and computers were needed. Now finding an extrasolar planet is like finding sea shells on the beach.

Quote: Nareed

finding an extrasolar planet is like finding sea shells on the beach.

DJTB has to be right, so since so many are being found you have to wonder if there is such a thing as a star without planets. Seriously. I can imagine it is quite rare [even then surely there are asteroid belts or something]. On the other hand, "Earths" in the habitable zone are a different matter.

Don't forget that "habitable zone" means "habitable for life as we know it; life that relies upon liquid water". It wasn't much more than a year ago that there was buzz about finding potential carbon-based life signatures on one of Saturn's moons, and there's an experiment ready to drop onto Mars to detect the presence of methane-producing organisms. It's on hold due to NASA budget, however. Point is, there are a lot more possible combinations for "life" than "liquid-water-based life".

Quote: odiousgambit

Seriously. I can imagine it is quite rare [even then surely there are asteroid belts or something].

Not really. Most stars do not have planets. I believe that the currently accepted estimate that about 40% of Sun-like stars have a planet system. Stars, that are much bigger or much smaller than Sun are much less likely to have it.

Quote:

The Hubble Space Telescope has spotted new evidence of complex organic molecules — the carbon-containing building blocks of life as we know it — on the frigid surface of Pluto,

here

You know, it might be interesting if we can accomplish virtual space travel through advances in our various observation techniques from near-space instruments. If our ability increases to collect information as well as our ability to build computerized virtual models of the information, then we could possibly create alien environments in a virtual world on Earth without leaving the planet. (I'm sure that's been explored in SF already). It could help solve the biggest problem inherent in interstellar travel (time and distance required to get there). It wouldn't totally substitute for actual space travel, but you might be able to extrapolate quite a bit of hidden information about things you can't see from extensive of data of what you do find, just like we do now.

Quote: odiousgambit

DJTB has to be right, so since so many are being found you have to wonder if there is such a thing as a star without planets.

That depends on what you call a planet. If you mean some body circling a star, I'd say all stars have them. They pretty much have to. Sizable bodies, say at least Pluto-size, are another matter. Some stars may not have any.

You know, it's interesting that we've tried to come up with planetary formation hypotheses based on one, and only one, example of a planetary system. At one time the idea was that a near collision between stars was needed to form planets, therefore they'd be exceedingly rare.

Quote:

On the other hand, "Earths" in the habitable zone are a different matter.

There are certain to be some. Yet, read up on Larry Niven. The man's a master at creating improbable worlds with intresting living conditions, partial habitability, and even non-planetary worlds. You'd think his Known Space has three regular planets and a host of freaks :)