PV Gap

Herbert Said:

Do all the stars we see in the sky belong to other solar systems and galaxies?

We Answered:

the stars you can see with the naked eye are all in our own galaxy. stars in other galaxies are too far away for us to individually make out(with the naked eye) some "stars" you see may be other galaxies though. All true stars are suns. Venus, though called the morning star, is not actually a star. It shines brightly in the sky appearing to be a star due to the light reflected off of it from our own sun.

Christina Said:

Why do scientists think that solar sails would be able to take probes to other solar systems in the future?

We Answered:

I read about this awhile ago. I think their plan was to just go ahead and let it get full of holes. So by the time it arrives at its destination, it'll be in much worse shape than when it started.

The problem with deep space exploration isn't the initial acceleration.. the problem is sustained acceleration.. the solar sail will let them accelerate continuously for a long period of time.. then once they reach the desired speed, they won't need to worry about sustaining the speed because of the lack of friction in space..

Jason Said:

How long will it be until a telescope is made which can see planets in detail in other solar systems?

We Answered:

Hi. We could probably see gross detail with two telescopes set up using interferometry. But it is difficult through the atmosphere.

Patrick Said:

Do you believe that life exists in other solar systems / galaxies?

We Answered:

Consider this:

Life has begun on earth at least a half dozen, and perhaps 8 times that are known.

1. Animals (including all reptiles, birds, fish, etc)
2. Plants (all chlorphyl producing light converting plants)
3. Fungi
4. Bacteria
5. Viruses
6. Slime-molds, which are poorly understood but are life, but are not in any of the former categories.
Also,
7. You could also argue that prions, which cause mad cow disease, yet are none of the above are life forms as well.
8. There are hydrogen sulfide breathing forms of life that live a mile or more deep in the vents of the ocean where temperatures are in the hundreds of degrees, and pressures are so high that no known life from anywhere else on earth can survive. They may very well be completely unrelated to anything listed above.

Each of these life forms is so different from the others that scientists cannot fathom any possible similar starting point. Presuming they are right (as we have to do in many cases to move forward), life has begun many times on this planet.

Given the understanding of life as we know it here on Earth, if there are billions of solar systems in this galaxy, and there are billions of galaxies, to deny that life outside of the earth exists when we know it started half a dozen times in one spot is to deny science to the point of mental blindness.

-Kevin

Vanessa Said:

How many planets earthlike have been found in other solar systems?

We Answered:

Not that we know of. However, at this point we wouldn't expect to be able to see them if there were.

Bigger planets are easier to see. (Because they are bigger.) Planets that are really close to their star are also easier to see. (Better lighting, they create a "wobble", and they block more of the star's light.) So far most of what we have been seeing are really gigantic "Jupiter-like" planets that are really close to their stars, (huge and bright) and smaller icy objects at the edge of our own solar system (really close). These are simply the easiest type of planets to see. With present technology we couldn't detect an Earth like planet unless it was practically our next door neighbor.

So far the biggest surprise is the number of huge "Jupiter like" objects orbiting really really close to stars. We did not think that was possible. The fact we have been seeing this many of these unlikely objects suggests that planets are really really common.

(The absence of evidence is only the evidence of absence if it is something you would expect to have noticed if it existed)