Astronomer: There may be 100 billion Earth-like planets in Milky Way

[Traditional_Ale]

Originally Posted by Mr.Coffee

I guess I gotta ask HOW scientists "know" about a lot of this stuff. I'm sure they know a lot but...

Because they have the audio journals of one Gene Roddenberry, who was actually captured by the CIA and experimented on. Star Trek was created in a lab and all kinds of drugs were tested on the cast. Ever wonder why William Shatner used to be able to play a reasonably cool character but now in reality hes a big fat washed up tub of bitterness and envy? Moving along though, because that is besides the point.

Gene Roddenberry has predicted so many technological innovations...cell phone, now the iphone I would call the Tricorder only about a million times cooler. Theres the atom smasher thingies in Sweden and France that create anti-matter and other speed of light type things. DNA, genetic engineering, cloning, robotic implants...yup..you guessed it...ALL GENE RODDENBERRY PREDICTIONS!!!

So in closing I say that the textbook on stars and outerspace and all that stuff is in fact just the recorded ramblings of a genius TV show writer.

Now, revel in the sheer overpowering epic awesomeness of the new Star Trek movie trailer:

[photon]

Originally Posted by Mr.Coffee

I guess I gotta ask HOW scientists "know" about a lot of this stuff. I'm sure they know a lot but...

It's all about observation, creating models, testing predictions, refining models, etc. The amount of research out there is staggering. Check this out:

http://arxiv.org/year/astro-ph/08

That's an average of what, 800 papers submitted in the subject of astrophysics PER MONTH. Arxiv is I think an open venue unlike a journal, but gives you an idea of the level of activity.

Originally Posted by Mr.Coffee

do they just sit there counting stars? And then make a guess?

Pretty much, they can point telescopes in different directions and count stars, types of stars, brightnesses, colours, distribution, etc etc.. I'm no expert, I'm sure evman could give exhaustive details on how they come up with their numbers.

Originally Posted by Mr.Coffee

How do they even know about the approx. size of the universe. Like honestly how big are these telescopes? It just seems a little fishy to me that they can make earnest predictions on numbers of stars and stuff.

They use many different ways to measure things like this, if the numbers all agree then that means the number is better supported than a number derived from just one observation.

They use things like globular clusters, supernovae, stars called Cephids, etc and ultimately the red shift of things moving away from us to determine distances of things, since light moves at a specific speed.

It's very deep stuff, and very fascinating. I wish I'd been an astronomer or cosmologist or something like that.

Originally Posted by Mr.Coffee

This stuff, I'm sure, is a lot more complex than I'm giving it any credit here but how do they know the universe has boundaries or "multiverses" (mentioned in this thread) or that there's more stars than pebbles of sand and stuff.

I don't think the universe has boundaries as such, does the surface of a sphere have a boundary? Multiverses are speculated but at this point it's all just that, speculation.

Originally Posted by Mr.Coffee

Aren't a lot of these "knowns" still theories?

You say that like it's a bad thing. In science a theory means a well supported framework of facts and hypothesis that has explanatory power and makes predictions that can be confirmed (or not confirmed). A theory is not a pie-in-the-sky idea.

[McG]

can you imagine 100 billion planets out there...

"where is this earth place that keeps sending space junk to look for us?"

[worth]

We get the size of the universe from COBE satellite and WMAP satellite.





http://en.wikipedia.org/wiki/WMAP

http://en.wikipedia.org/wiki/COBE



Michio Kaku on the Multiverse:

[jammies]

Originally Posted by octothorp

For the most part, I understand the concept of having an infinite number of universes, but why is this always equated with infinite possibilities? Isn't it equally possible that the infinite number of universes are all exactly the same, or that the number of realities is some finite number between 1 and infinity? There's a finite number of particles in the universe, and a finite number of ways in which these particles can interact with one another.

I think physicists are over-enamoured with the idea of infinity; just because you can use mathematics to describe reality doesn't mean mathematical concepts are reality - we live in a universe that is unbounded but NOT infinite and there is no reason to expect that the multiverse (if it even exists) is any different other than sheer speculation.

Just for example, in the "many worlds" interpretation of QM, the world splits out into possible universes at a furious rate as quantum events take place, but if you start with ONE universe at the point of the Big Bang, you don't end up with infinite universes, you just end up with an extremely large number of them, which isn't the same thing at all.

Other multiversal theories also throw infinities around casually, but these theories are little more than guesses dressed up in equations.

[Hack&Lube]

Originally Posted by Daradon

This seems far to high/extreme to be possible.

If there were THAT many civilizations on our galaxy alone at least a few would have to have evolved to the point of being able to visit us, or somehow communicate with us.

Or we would see signs of them as they colonize the stars.

His values are FAR too high. It doesn't make logical sense at all.

You seem to be unaware of the actual scale of galaxy, much less the universe. Even if it was on the order of magnitude of billions of intelligent spare-faring species...the sheer size of the Universe still makes the chances of interspecies contact less likely.

[Hack&Lube]

Originally Posted by Daradon

Show me a fossil from another planet. Show me a single celled organism from another planet.

That's assuming carbon based life. Who knows what basis other life can take. Silicon based life maybe? What would it even look like?

[PsYcNeT]

Originally Posted by Hack&Lube

That's assuming carbon based life. Who knows what basis other life can take. Silicon based life maybe? What would it even look like?

[T@T]

The search vessel blasted off tonight!

"The Kepler spacecraft blasted into space on top of a Delta II rocket from Cape Canaveral Air Force Station in Florida.
The telescope will search our corner of the Milky Way galaxy for Earth-like planets.
"This is a historical mission. It's not just a science mission," NASA Associate Administrator Ed Weiler said during a prelaunch news conference."

"Mission goal is to find Earth-like planets with potential to have liquid water on surface"

http://www.cnn.com/2009/TECH/space/0...tml#cnnSTCText