Study suggests every star likely has planets.

Dannyalcatraz · Jan 13, 2012

I think the concept that every star likely has planets is very cool, but there are still too many variables for determining the likelihood or numbers of other possible intelligent life.

Including time: are they alive now, were they alive then but died out, are they yet to evolve?

Umbran · Jan 13, 2012

El Mahdi said:
Of those 10 billion Earth sized planets, how many are in the "habitable" zone of their star...?

And for that matter, how accurate is our assumption of what the "habitable" zone of a star is...? So far, that assumption is based on a sample of 1...

Maybe you misunderstand the term. It isn't an assumption, it is a definition. "Habitable zone" isn't intended to mean, "the zone in which something we'd call life could exist". It is intended to mean, "the zone in which humans could live". Which, honestly, reduces to "the zone in which liquid water may exist on the surface for geologic/evolutionary timescales".

Olgar Shiverstone · Jan 13, 2012

Kaodi said:
But also remember, detecting other intelligent life may not be limited to detecting radio signals. Perhaps the thought is that if you know what you are looking for, there may be other ways to figure out if a planet and its neighbourhood have been doing something unnatural...

We'll know when the stars blink out 'cause the aliens have built Dyson spheres around them.

Janx · Jan 13, 2012

Olgar Shiverstone said:
We'll know when the stars blink out 'cause the aliens have built Dyson spheres around them.

given a certain distance from the sun, wouldn't the amount of matter needed to envelope the sun be greater than most solar systems have in entirety?

Wouldn't that then produce some new wierd gravity distortion?

Though the key idea is that we might be able to detect some super science event because it's bigger wierder than the rest of the universe's behaviors.

El Mahdi · Jan 13, 2012

Umbran said:
Maybe you misunderstand the term. It isn't an assumption, it is a definition. "Habitable zone" isn't intended to mean, "the zone in which something we'd call life could exist". It is intended to mean, "the zone in which humans could live". Which, honestly, reduces to "the zone in which liquid water may exist on the surface for geologic/evolutionary timescales".

Actually no. The last part about liquid water is correct, but not necessarily about Humans. It is about what we would call life. Life as we know it cannot exist without liquid water. But that definition is only due to our own observations. Observations which are limited to our own system. Which isn't even necessarily true here as there may be life under the ice of Europa or even other solar bodies well outside of what we consider our habitable zone.

I think it's an assumption to state that life only occurs where liquid water is present. Just because it holds true so far, with the very limited exploration of our own system, does not mean that this will remain true. We won't know until we get out there.

Olgar Shiverstone · Jan 14, 2012

Janx said:
given a certain distance from the sun, wouldn't the amount of matter needed to envelope the sun be greater than most solar systems have in entirety?

Wouldn't that then produce some new wierd gravity distortion?

Though the key idea is that we might be able to detect some super science event because it's bigger wierder than the rest of the universe's behaviors.

Not really, no, since the sphere is the equivalent if infinitesimally thin compared to the scale it's on. We're not trying to fill the entire solar volume, just put a very thin shell around it. Plus it's gravitationally neutral since its center of mass remains the center of the primary.

And if you have the tech to build a Dyson sphere, you certainly have the tech to take down not only your entire solar system (to include the large mass in the Oort cloud) but also raid nearby systems as well).

Dannyalcatraz · Jan 14, 2012

And if you have the tech to build a Dyson sphere, you certainly have the tech to take down not only your entire solar system (to include the large mass in the Oort cloud) but also raid nearby systems as well).

I KNEW those cannister vacs we're good, but I had no idea!