Need South Hem. NEAR obs; charts; Sunglint seen

Joan and David Dunham (
Fri, 23 Jan 1998 07:12:48 -0500

1.  Charts on Web site to help southern hemisphere
   observers - data needed before NEAR gets too far away.
2.  Sunglint seen in Southwest, 3rd mag., not 0 mag.
3.  Movies of NEAR coming in
  some details below:
1.  NEAR is now favorably placed for observation from New Zealand
and Australia - astrometric observations as soon as possible may
be of some value while the distance is not too great (since 
astrometric errors are angular, the linear error, important to us,
is proportional to the distance).  You probably already have a 
topocentric ephemeris from the Web sites given previously.  My
plots showing the track of NEAR across Circinus and Musca as 
computed for a few cites are at
Look at "Chart 4", a PPM-based chart covering the area south of
Alpha and Beta Centauri.  It shows the path from now until about
13h U.T. today.  The faintest stars on it are about mag.
11.5, but it is reasonably complete only to about 10th mag.
The track for Auckland, New Zealand, crossing the middle of the
chart near Alpha Circini, was inadvertantly not labelled.
"Chart 3" is a more detailed chart of southern Musca based on
ACT data augmented with PPM; it shows NEAR's path after about
13h U.T. to the end of the day.  South Africa will see NEAR
at about 18h U.T., and South America near the end of the U.T.
day Jan. 23rd.  The faintest stars on chart 3 are about mag.
12.0, but the chart is reasonably complete only to about mag.
11.2.  Let me know if any information is needed for
Jan. 24th U.T., although by then the distance may already be
too great to be of any use.
2.  Several observers in southern California and southern
Arizona, and one in Hawaii, have reported seeing the Sunglint.  
It was about mag. 3.0, with one report of it being 2nd mag. 
briefly.  In general, it lasted longer and was a more gradual 
phenomenon than expected, and fainter than predicted.  Perhaps
the solar panels are warped a little, not like an optically
flat mirror.  An image-intensified video was obtained at
Central Arizona College in Casa Grande showing NEAR moving
among the stars before the glint, then brightening, etc.
The unglinted mag. has been reported at 8th or 9th, a little
brighter than expected, at the time.  More on this later.
3.  Animations of NEAR have been made from CCD images
obtained at the Observatoire de la Cote d'Azur in France
and the TIRGO observatory in Switzerland, and place on their
Web pages.  Later today, we will provide links to these on
the NEAR and IOTA Web pages.
Of course, it rained here in Maryland during the Sunglints;
I "watched" them via NEAR telemetry at the NEAR Operations
center.  NEAR was followed all the way down to the 6-deg.
cutoff by the Goldstone, Calif. antenna, and was picked up
again a little more than an hour later with the Canberra,
Australia, Deep Space Network antenna.

David Dunham, 1998 Jan. 23, 12:30 U.T.