glenn@LL-VLSI.ARPA (Glenn Chapman) (02/13/89)
The USSR's Phobos II probe on Feb. 12 raised its orbit from the
capture one of 4200 km (2610 mi) x 79,000 Km (49,100 mi) to the
second transfer one of 9700 Km (6030 mi) x 79,000 Km (49,100 mi). (The
orbits here are from the planet center, not from the surface as is
common for earth orbits). This change also moved the orbit to an
equatorial one, which is completely outside of the moon Phobos's path.
Initial plans had called for this to occur on Feb. 22, but the Russians
decided to move the rendezvous with Phobos up to about 60 days after
the initial insertion or about March 31st. The unstated reason is their
worry about the health of the probe. In this new orbit the satellite will
continue its study of Mars itself, however the new periapsis is 2630 Km
(1640 mi) above the surface, compared to the initial minimum height of
800 Km (500 mi). One other point, on Feb. 2 there were statements
that communications had started with the probe. However, there has been
no confirmation on the shortwave of the receipt of pictures (CBS radio
stated that the first ones have been received). Nor has any of my
contacts been able to confirm the CBS report. This may be tied to
earlier reports of transmitter problems. If anyone has better
information please contact me.
Hopefully, Phobos II will still bring us the first real information
about that Moon of Mars.
Glenn Chapman
MIT Lincoln Lab