Starlight Starbright: How Many Planets Will I Find Tonight

February 6, 2015 8:27 PM

14 0

Last time we talked about Habitable zones around stars within which orbiting planets can support liquid water. Liquid water as far as we know, can lead to life like us. It happened here after all. But how do we find these planets? Can we see them directly? The short answer to the first question is that it's immensely difficult. The shorter answer to the second question is no, not really. Those answers are not very satisfying I realize, but we will discuss one way in which we actually do find planets around other stars and how it has opened up the Universe to us in ways we never dreamed. The problems associated with finding planets may seem insurmountable at first glance because even our best telescopes are hopelessly unable to resolve the round shape of the stars themselves which vastly outsize any planets. Except for a few notable exceptions, nearly all stars appear as mere points of light because their distance simply precludes our current capabilities from seeing otherwise. Let's look at a cool analogy to understand the issue and how it relates to planets.

Alpha Centauri is the nearest star system to us. One of the stars in the system, Alpha Centauri "A", is much like our Sun and is four light years away from us. The question is this: If we put Alpha Centauri "A" in our camera view, how far away from the camera would we have to move an ordinary U.S. q...

Read more

To category page