Tristan Cools wrote: > I would suggest to compare it with the Ajisai(86-61A) which > is of similar design and in a much higher orbit. This ball > with mirrors produces sharp flashes constantly. Since October 1990, Russell Eberst has reported 37 position, magnitude and flash period observations of 86061A / 16908. The observed magnitude of flashes typically was about 6th magnitude. Observed minima were near 9th magnitude, which would be barely visible in 11 X 80 binoculars. Standard magnitude (1000 km, 90 deg phase angle) of the flashes is about 4. Russell reported a flash period of 0.4 s, which is sufficiently frequent not to significantly degrade positional obs. Residuals seem about as accurate as his other observations. Starshine 3's flashes appear to be far too infrequent to enable accurate positional observations; however, its size and altitude may make its body visible in 11 X 80 binoculars under the most favourable conditions. The body appears to be fairly dark, but it does reflect some light, as shown in this photo: http://www.azinet.com/starshine/ss3sat1_big.jpg I am not familiar with the design issues, but it seems to me that it might have been better to have a lighter coloured body, to enable the object to be observed using binoculars, as a hedge against infrequent flashes. Flashing or not, binoculars are required to see close pairs of reference stars to enable precise positional measurements, so I see no harm in making the body bright enough to see in binoculars. The body would be invisible to the unaided eye, so the full effect of the flashing would be preserved for casual observers. I understand that the soon to be launched Starshine 2 carries micro-thrusters to ensure that it will spin, and that future Starshines may have a re-spin mechanism. Ted Molczan ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www.satellite.eu.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Wed Oct 10 2001 - 23:40:42 EDT
