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Telescopes Zoom in on Quasar Near Edge of Universe

March 4, 1995

CAPE CANAVERAL, Fla. (AP) _ Astronomers in space and on the ground cheered Saturday when ultraviolet telescopes aboard Endeavour zoomed in on a quasar near the edge of the universe, an incredible 60 sextillion miles away.

The quasar, the most distant and desired target of the astronomy mission, appeared as a very faint pinpoint of light to ground controllers. It was invisible to the shuttle crew.

The quasar is 10 billion light years away, or 60 sextillion miles _ 60 followed by 21 zeros.

``This observation is right at the limit of what can possibly be done with this camera,″ said Arthur Davidsen, an astrophysicist at Johns Hopkins University. ``It’s the hardest thing we can do with this telescope, and it looks like it’s going to work.″

Davidsen wants to use this ultraviolet radiation-rich quasar in his search for intergalactic helium, supposedly formed within minutes of the Big Bang. Astronomers believe the universe was created in an immense explosion and that lots of hydrogen gas and much less helium gas ultimately were spread between galaxies.

The Hubble Space Telescope may have spotted this primordial helium a year ago, said NASA scientist Edward Weiler. But scientists need to confirm this because Hubble was not designed to observe such short wavelengths.

``That would be a very important confirmation of the Big Bang theory, that yes, indeed, there was 10 percent helium and 90 percent hydrogen,″ Weiler said. ``If it doesn’t confirm it, then we have a lot of problems.″

The quasar, short for quasi-stellar object, is thought to be the size of several billion solar masses all collapsed into one giant black hole. This suspected black hole is sucking up everything around it and emitting considerable light at the far end of the ultraviolet spectrum.

By using the quasar as a light bulb, the Johns Hopkins telescope should be able to see whether anything is blocking its far-ultraviolet light. The obstructing material could be intergalactic helium.

Saturday morning’s observation was meant to pinpoint the location of the quasar and study the surrounding area. The helium search was expected to begin later Saturday and continue throughout the 15 1/2-day mission ending March 17.

``We literally won’t have enough information until we’ve done this a half-dozen times,″ Davidsen said.

The astronauts also aimed the three, $200 million telescopes at Io, one of Jupiter’s moons. The Johns Hopkins telescope could detect ultraviolet emissions from the sulfur and other materials apparently spewing from an erupting volcano on Io. The measurements appeared on television as a line of squiggles.

Four of Endeavour’s seven crew members are astrophysicists.

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