Other Forms of Life (Evolution)

by David Turell , Saturday, December 06, 2008, 00:59 (5830 days ago) @ BBella

BBella: Without quoting your message let me answer in this way. There are 92 basic elements in the universe and they are everywhere, especially carbon. For example in our solar system the Earth has iron, but Jupiter does not. The elements after helium, hydrogen and lithium were all formed in the hot high pressure furnace of stars, by combination and growing in size as added together, and were scattered when the stars grew old and exploded. Carbon atoms can be strung together in long chains and various loops. For example, six carbons in a loop make benzene. Silicon has this same property, but is not as versatile as carbon in making molecules compatable with life as we know it. One DNA molecule is 6 feet long, if stretched out. As you know DNA and RNA are codes for making protein and for telling genes what to do. I think you understand now that DNA/RNA patterns on Earth are peculiar to Earth. Foreign DNA will stand out like a sore thumb. If life is present elsewhere based on our knowledge of the 92 elements, it must be carbon based as it is here. - The universe is 13.7 billion years old. Our sun is 5 billion years old and the Earth is 4.5 billion years old. Life appeared on Earth at about 3.6 billion years ago. With the right conditions on a planet life appears rather quickly. Considering the size of the universe, 100 billion galaxies, each with 100 billion stars carbon-based life should be out there, but it takes a very special planet to have life. Considering all the special things about Earth, the number will be quite small. - Does that help?