re: WIRE Elsets + Visibility

Philip Chien (kc4yer@amsat.org)
Fri, 5 Mar 1999 16:10:52 -0500

Mir16609@aol.com said:

>These elsets from OIG would suggest visible passes this evening for the USA:
>
>UNK                                              591 x 540
>1 25648U 99011C   99064.49820708  .00063660  00000-0  49751-2 0    36
>2 25648  97.5279 259.9924 0036585 167.6037 192.5907 15.00281204    65
>UNK                                              585 x 540
>1 25647U 99011B   99064.16470773 +.00001241 +00000-0 +10000-3 0 00035
>2 25647 097.5454 259.6678 0032625 171.9763 188.1679 15.01324543000003
>WIRE ?                                           588 x 539
>1 25646U 99011A   99064.36482496  .00000000  00000-0 -16070-1 2    37
>2 25646  97.5325 259.8708 0035257 167.5521 192.6468 15.01107549    36

My guess is the additional object (B?) would be the cover of the cryogenic
dewar which was ejected after injection in to orbit.  It would be a fairly
small object.  Normally with a single satellite Pegasus launch you'd expect
to see only the payload and 3rd stage in orbit.

According to NASA the WIRE spacecraft is in a spin which is shouldn't have.
The best guess is the cyrogen is venting in some propulsive manner.

exerpt from the NASA press release -

>NASA WORKING TO CORRECT SPIN RATE OF WIRE SPACECRAFT
>
>       Ground controllers are attempting to recover a NASA
>spacecraft that was unable to maintain a stable position in orbit
>after launch Thursday.
>
>      The Wide-Field Infrared Explorer (WIRE) spacecraft began to
>experience a problem during its second pass over a ground
>station, following a successful launch at 9:57 p.m. EST from
>Vandenberg Air Force Base, CA. The Poker Flats, AK, ground
>station determined that WIRE was still spinning instead of
>maintaining a stable position in orbit and was warmer than
>expected.  The WIRE team has declared a spacecraft emergency and
>is communicating with the spacecraft while attempting to slow the
>spin rate and cool the WIRE spacecraft.
>
>       "Recovery of the spacecraft is our top priority," said Ken
>Ledbetter, Director of the Mission and Payload Development
>Division in the Office of Space Science at NASA Headquarters,
>Washington, DC.  "The spacecraft carries frozen hydrogen to cool
>its instrument, and we believe that the hydrogen is venting as it
>warms up, causing the spacecraft to spin.  However, at this time,
>spacecraft controllers do not know what specifically caused the
>situation."


Philip Chien, KC4YER
Earth News
world (in)famous writer, science fiction fan, ham radio operator,
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