Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: notesfiles
Path: utzoo!watmath!clyde!bonnie!akgua!sdcsvax!sdcrdcf!hplabs!hp-pcd!hpfclp!fritz
From: fritz@hpfclp.UUCP (fritz)
Newsgroups: net.space
Subject: Re: Orphaned Response
Message-ID: <15500002@hpfclp.UUCP>
Date: Fri, 14-Dec-84 17:04:00 EST
Article-I.D.: hpfclp.15500002
Posted: Fri Dec 14 17:04:00 1984
Date-Received: Sat, 22-Dec-84 02:22:19 EST
References: <22000006@hpfcla.UUCP>
Lines: 45
Nf-ID: #R:hpfcla:22000006:hpfclp:15500002:37777777600:2434
Nf-From: hpfclp!fritz    Dec 17 14:04:00 1984

One of the German  scientists  described  the mission  very  poetically:
"What we want to do", says  physicist  Bernd  Hausler, "is paint the sky
and look at it as it moves."

The  following  information  is reprinted  without  permission  from the
December issue of Science84.

Gary Fritz
{ihnp4,hplabs}!hpfcla!fritz


  Four  cannisters  are to separate  from the  spacecraft  and  explode,
  releasing  five  pounds of barium  atoms.  The sun's  photons of light
  will bump the barium atoms,  exciting them and causing them to radiate
  in several  wavelengths.  During the first few seconds, when the atoms
  are still  clustered  tightly, the barium will glow a reddish  yellow.
  The more diffuse  atoms at the fringes  should appear  green, and then
  the  whole  ball of gas may  turn  green as it  expands  at a mile per
  second.  Eighty  seconds after the release, the ball will have reached
  its maximum size, at least a sixth the size of the full moon.  
    [I assume they mean it will *look* 1/6 as big as the moon -- at 
     1 mi/sec for 80 seconds it will actually be only 160 miles in 
     diameter.  I think.] 
  By then the sun's  photons of light will have bumped loose an electron
  from  most of the  barium  atoms.  Once  the  barium  is  electrically
  charged, it will change color and be  susceptible  to the solar wind's
  magnetic  influence, which will promptly start blowing the ions into a
  tail.

  ... The artificial comet is scheduled to appear on December 25 at 4:16 
  AM Pacific Time.  It will form 70000 miles above the Pacific Ocean six
  degrees west of Lima, Peru, and nine degrees south of the equator.

  To see it, you'll  have to be in the dark,  which for North  Americans
  means  roughly  being  west of a line  running  through  Mexico  City,
  Houston, St.  Louis,  Milwaukee,  and Canada's  Belcher  Islands.  The
  comet should  appear four degrees to the right of Spica, the brightest
  star in the  constellation  Virgo.  (A viewer in Los Angeles would see
  it 33 degrees  above the  southeastern  horizon.)  Then it should move
  west toward the star Regulus in the constellation Leo.

  As the comet grows  fainter, the green and purple  colors will be hard
  to  distinguish  -- it might simply  appear white or gray.  Scientists
  say it may be visible for three minutes with the naked eye, 10 minutes
  with binoculars.  For more details, call NASA at (301) 344-0470.