I'm sitting in my favorite chair looking at a picture in the October 2003 issue of Sky & Telescope. It covers all but the bottom 2 inches of pages 46 and 47. There is an inset showing the portion of sky that is represented. It is a small section just above M31 (the Andromeda Galaxy). If you hold a grain of sand at arms length you can get an idea of the actual amount of the sky that is shown in this photo. Also, to the naked eye this grain of space looks black and devoid of stars. It is anything but.

There are thousands of stars in this photo. Many more than I could count. No square centimeter holds less than a dozen. There are several star clusters, concentrations of light holding thousands and perhaps millions of stars. And there are several hundred discreet galaxies, each holding perhaps as many stars as are contained in our own Milky Way. It is amazing. And that is the fascination of space. It's ability to constantly amaze.

In Washington, D.C. earlier this week I took time to visit the NASA museum. There is a full scale replica of the Hubble Telescope on display. I stood there trying to imagine the real Hubble in orbit above us, viewing the heavens and mapping more deeply than is possible with anything we have on earth. And I wondered what we will put into space in future generations. Perhaps we will be able to send a telescope to the edge of our solar system. Then we could view parts of the universe that right now are unimaginable. It won't happen in my lifetime with the current capabilities of our technology. But it will likely happen.

Scientist calculate that, with conservative probabilities and assumptions, in the Milky Way alone there are millions of worlds just like our own. Prior to Hubble we were unaware of any other Suns with planets. Now we know of many such systems. The speculations is that 5% or so of stars have planets associated with them. Of the newer stars, those that were born less than 6 billion years ago, the odds of having planets go up to more like 1 in 5 (20%). That is because the earliest stars were created in an environment that was rich in gases and less rich in the heavier elements. As time has progressed the heavier elements have become more abundant in our universe. And it's the presence of these heavier elements that increases the likelihood of planet development along with the stars. At least at present this is the best theory available. We certainly will learn more as we increase our ability to look farther into the universe...........
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