[continued from part 1}
The most significant change has been the computer, which is allowing
astronomers to aim and focus telescopes, gather data and analyze it in
ways impossible a decade ago. This is coupled with the launch of space
telescopes using both visible light and other parts of the light
spectrum such as infrared, plus a profusion of better, cheaper ground
telescopes.
Telescopes focusing on other parts of the light spectrum have produced the
first strong evidence of planets orbiting other stars.
Astronomers have also learned to take clever advantage of nature. Because
light can take billions of years to reach Earth from distant objects, we
can observe galaxies of stars as they appear in the past, turning the sky
into a time machine. And because relativity bends distant light as it
passes the gravitational attraction of objects, light from dim sources
is artificially brightened by this "lens" effect, allowing more detail to
be seen.
Such improvements are raising as many questions as they are answering.
While astronomers have found compelling radiation echoes of a Big Bang
that may have started the universe, the process that led to the
formation of galaxies, stars and planets is still poorly understood.
Also unknown is the composition of anywhere from half to 99 percent of
the matter in the universe, judging by how galaxies spin in relation to
gravity. Some of the "dark matter" or "missing mass" appears to be in
the form of dark or dead stars, near stars called brown dwarfs, planets
and debris, but most of what creation is made of remains a mystery.
Ultimately we are trying to understand the universe's origin and fate,
explained Hugh Van Horn, director of astronomical sciences for the National
Science Foundation. Right now, tax dollars are being directed primarily
toward study of how teh universe evolved after the Big Bang, continued
detection of new planets around other stars, exploration of our solar
system and understanding of our sun.
"We've discovered amino acids in space," Van Horn said, referring to
the prescence of ammonia and vinegar that could combine to form them.
"It's not that big a step from that to proteins and DNA. And it is the
radio astronomers who are providing the hard evidence."
[end of article]
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