Saturn's Rings:
(SFX: astro music) 
     SATURN'S FAMOUS RINGS ARE SO BIG YOU CAN SEE THEM THROUGH A COMMON
PAIR OF BINOCULARS.  BUT TO REALLY STUDY THEM TAKES A BIG GUN--THE HUBBLE SPACE
TELESCOPE.  IN AUGUST OF 1995 SATURDN WAS ALIGNED JUST RIGH FOR SOME GOOD
RESEARCH WITH THE RINGS TILTED ON THEIR SIDE.

     Hall: "That's when the rings from the earth looked edge on and if you can imagine
taking a piece of paper . . . and turning it until it is edge on towards you.  you don't see
the surface of the paper anymore, you just see the edge and it looks very thin from that
perspective."

     ASTRONOMER DOYLE HALL AT JOHNS HOPKINS UNIVERSITY SEIZED THE
OPPORTUNITY TO LOOK FOR A GAS THAT'S BEEN LONG HYPOTHESIZED TO HOVER
AROUND THE RINGS.  THE RINGS ARE MOSTLY MADE UP OF WATER ICE PARTICLES, SO
SCIENTISTS HAVE SUSPECTED THAT THE RINGS SHOULD BE LOSINGGREAT ROLLS OF STEAM
INTO SPACE.  AND SO IT WAS, SAYS HALL-- THOUGH THE GAS IS VERY THIN INDEED.

     Hall: "We learned how brightly its glowing and from that brightness we can
determine how much gas there is and it turns out . . . that translates into what would be
space to you and me. in fact that's bit thinner gas than the astronauts go up to when
they go up in the shuttle. "

     BY EXAMINING HOW MUCH GAS THERE WAS, ASTRONOMERS FIGURED OUT THAT
SATURN'S RINGS ARE LOSING A FEW TONS OF WATER PER SECOND.  THAT SOUNDS LIKE A
LOT,  BUT  HALL SAYS THAT THE RINGS ARE SO BIG THAT EVEN AT THAT RATE THEY'LL LAST AT
LEAST SEVERAL BILLION YEARS--WHICH STILL LEAVES YOU PLENTY OF TIME TO GO LOOK AT
THEM THROUGH YOUR BINOCULARS.