The Comet Nursery

(SFX: vibraphone music)

     EVERYONE KNOWS PLUTO AND NEPTUNE ARE THE FARTHEST PLANETS, RIGHT?     
     Cochran: "It would be unlikely if our solar system ended at the orbit of neptune." 

     BUT ASTRONOMER ANITA COCHRAN AT THE UNIVERSITY OF TEXAS AT AUSTIN HAS
JUST DISCOVERED OTHERWISE.  USING THE HUBBLE SPACE TELESCOPE, SHE LED A TEAM
THAT DISCOVERED A WASTELAND OF ORBITING DEBRIS, FAR PAST NEPTUNE AND PLUTO,
THAT WAS FIRST HYPOTHESIZED BY GERARD KUIPER IN 1950.  BUT NO ONE HAS BEEN ABLE
TO SEE THESE TINY COMETS UNTIL THE HUBBLE TELESCOPE CAME ALONG.

     Cochran:  "We wanted to find things which were the radius of about 5 km, and
these things are out beyond the orbit of neptune, so these are the size of the island of
manhattan,. . .these are the color of coal, they're really really black, they're 30 to 50
times further from the sun thatn the earth,. . . think about seeing a dime ten times further
than the moon.  Hubble was able to do that." 

     COCHRAN AND HER TEAM HAVE CALCULATED THAT THERE ARE 100S OF MILLIONS
OF BODIES IN THE KUIPER BELT. THIS IS WHERE COMETS, SUCH AS HALLEY'S COMET COME
FROM, SAYS ANOTHER TEAM MEMBER, HAROLD LEVINSON FROM THE SOUTHWEST
RESEARCH INSTITUTE.

     Cochran:  "We are actually seeing comets in the place where they're formed."
     
     THE TEAM THINKS THESE BABY COMETS WERE ON THE WAY TO BECOMING PLANETS,
WHEN THE SUN MATURED.  

     Cochran: "the early evolution of the sun just halted the evolution out there, and so
its fascinating to us. . . to actually see a stage of planetary formation halted in mid-process, and forzen for billions of years." 
     
     THE TEAM HOPES THAT THIS COMET NURSERY WILL TEACH THEM NOT JUST ABOUT
THE  FUTURE OF COMETS BUT ABOUT THE PAST OF PLANETS AS WELL.