Volume 1, Issue 1 
1st Quarter, 2006

Astrobiology: What Are the Characteristics of Life?

Barry Blumberg, Ph.D.

This article was adapted from a lecture given by Barry Blumberg at the First Annual Workshop on Geoethical Nanotechnology on July 20, 2005. The Terasem Movement is devoted and dedicated to the extension of life in all its beneficent aspects. Therefore, it's very appropriate that we begin our deliberations with the overview of just what is it that we are talking about. What is life?

There isn't a single definition of life. Much what we're going to be talking about - nanotechnology and the possible applications of it - often come up against this issue: Are they life-like? Therefore, it is useful to talk about the recognized characteristics of life. I worked on the Hepatitis virus for many years and by unusual circumstances, became director of the NASA Astrobiology Institute. As a consequence, I had to learn about astrobiology, so I'm going to talk about this question in that context because it does address this very issue.

Hubble Deep Field
Figure 1

Figure 1 is the Hubble Ultra Deep Field, taken in 2004 by making multiple exposures during different orbits of the Hubble that would register exactly in the same place. In doing so, they selected a part of the sky that was quite dark. That is, if you looked at it with a telescope, you wouldn't see many stars. In effect, that meant there was a lot of open space between you and very distant events and it collected a great deal of light. This shows the sky - the universe, the cosmos - as it was probably within one or two billion years, perhaps even earlier, after the "Big Bang." It's a very unusual photograph because you're looking into distance and into time because the images (the light) that you're seeing started those billions of years ago and finally emerged and was registered on the telescope.

This gives you this sense of the depth and immensity of the cosmos. Figure 2 is a picture that was taken as Apollo 11 was going towards the Moon. It is the most frequently-used image that NASA has and may be the most frequently-used of any image.

Figure 2

This photo changed our perspective of the world, where we could now see it at a distance as we might see it if we were beings from other places that were approaching the earth. It gave us a sense of a beautiful green, white and blue continent filled with life. You can't see any borders - just clouds, water, land, and vegetation. In a way, this image changed very much our image of the world. 

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