Mir manoeuvres

Bruno Tilgner (Bruno_Tilgner@compuserve.com)
Mon, 27 Apr 1998 18:07:47 -0400

Russel Eberst wrote:

>In "New Scientist" (issue 2131, 25 April 1998, page27) Nigel Henbest wri=
tes
> "Mir is continually boosted to save it from a similar fate."
>
>Have I missed something? I have not detected a single orbital boost for =
Mir for
>at least six months, and this confirms Tony Beresford's opinion.
>
>Has anyone got an idea what was the date of the last raising of Mir's or=
bit?

The last raising took place more than a year ago, on 15 April 1997. On th=
at day
the mean motion changed from 15.6098300 rev/day to 15.5918132 rev/day.

Given the relatively high cost of these boosts I suspect there won't be m=
any,
if any, before Mir will be abandoned when ISS becomes operational.

On the subject of Mir: on 27 May the difference between the RAAN of Mir's=
 orbit
and the right ascension of the Sun will be nearly 90 degrees. Mir will th=
en be
in continuous sunlight and be visible on every pass from mid-northern lat=
itudes.
This should provide an excellent opportunity to observe the docking of ST=
S-91,
the last shuttle flight to Mir, scheduled for launch on 28 May.


Bruno Tilgner
48.85N 2.20E UT+2