Atlas 5 Fuel Dump?

A group of fellow ASH members and I saw a "cloud" from the Naylor
Observatory last night (2003/7/18 UT) between approximately 1:50 and
2:30 UT. First seen low in the southwest it moved eastward rapidly
northeastward. Through binoculars and a 5" f/5 finder scope the
object initially appeared to be roughly triangular with a somewhat
condensed head. Later we viewed it with a 12.5" Newtonian and a 17"
classical Cassegrain. Its speed was striking. I noticed two
bifurcated "tails" through the large telescopes. The cloud became
increasingly difficult to see when it passed underneath Arcturus.

A satellite was launched that evening by an Atlas 5 (see
http://www.space.com/missionlaunches...ch_030717.html ). We
assumed the cloud was the result of an orbital fuel dump by that
vehicle. I saw such a fuel dump some time ago during an Ariane
launch.

Was it in fact a fuel dump from that launch or another or a TMA
release perhaps?

Dave Mitsky
Harrisburg, PA

Dave Mitsky wrote:

A group of fellow ASH members and I saw a "cloud" from the Naylor
Observatory last night (2003/7/18 UT) between approximately 1:50 and
2:30 UT. First seen low in the southwest it moved eastward rapidly
northeastward. Through binoculars and a 5" f/5 finder scope the
object initially appeared to be roughly triangular with a somewhat
condensed head. Later we viewed it with a 12.5" Newtonian and a 17"
classical Cassegrain. Its speed was striking. I noticed two
bifurcated "tails" through the large telescopes. The cloud became
increasingly difficult to see when it passed underneath Arcturus.

A satellite was launched that evening by an Atlas 5 (see
http://www.space.com/missionlaunches...ch_030717.html ). We
assumed the cloud was the result of an orbital fuel dump by that
vehicle. I saw such a fuel dump some time ago during an Ariane
launch.

Was it in fact a fuel dump from that launch or another or a TMA
release perhaps?

Dave Mitsky
Harrisburg, PA

Dave, we saw the V shaped "cloud" from here in Northern Virginia last night as
well. It was a rather amazing thing to look at thru the scopes. Visible for some
30 to 45 mins or so. On the club's email list this morning, Geoff Chester of the
USNO confirmed that it was indeed a fuel dump.

Quoting Geoff Chester:

"What everybody saw was the fuel dump from the Centaur upper stage from last
night's Atlas-5 launch from Cape Canaveral. The rocket launched at 7:45 pm
EDT and released its payload (Rainbow-1 Direct-TV comsat) at 9:25 pm. Both
the Centaur upper stage and the satellite were injected into a geostationary
transfer orbit of 35,845 km apogee, 3,790 km perigee, and 17.5 degree
inclination. The fuel dump acts to deflect the Centaur from possible
collision with the payload, and assures that there are no possibly explosive
propellants on board should the tanks be punctured by a micrometeorite.

TTFN,

Geoff Chester
USNO Public Affairs Office
"

Clear Skies,
Alan Figgatt