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BAA electronic bulletin No. 00444 http://www.britastro.org/
======================================================================
UNUSUAL ROCKET FUEL DUMP SIGHTED
A Centaur rocket caused a minor sensation on Sunday night, October 18, when
it flew over Europe and dumped a load of surplus propellant. On its second
orbit of Earth following launch earlier on Sunday afternoon, the Centaur
rocket had fired itself out of Earth orbit into a heliocentric orbit as it
travelled northwards over Europe shortly before 19:15 UT. A couple of
minutes later it began to dump surplus fuel, a process that continued for
around 13 minutes. This led to the appearance of an unusual, cloud-like
structure that was easily visible to the naked eye.
When first sighted from the UK, soon after 19:15 UT, the cloud of propellant
looked like a comet with a slightly fan-shaped tail travelling from south to
north. About 20 seconds later, a second object appeared. This was the US
military weather satellite (DMSP F-18), which the Centaur booster had helped
launch some three hours' earlier from Vandenberg Air Force Base (AFB) in
California. This was in turn followed by a quite remarkable large circular
halo which trailed the two previous objects in formation across the sky.
This large circular halo was probably an expanding puff of gas emitted
during an earlier firing of the Centaur.
The events were witnessed by John Fulcher from Cransford in Suffolk, who
described what he saw as follows:
".outside with telescope looking at various astronomical sights, looked up,
and saw an odd small cloud, but no cloud cover in sight, (sky) quite clear.
Then another, very similar, if not exact, cloud-like shape following on
behind, keeping formation. Tried to follow with telescope but travelling too
fast, so used binoculars, and followed them north to south; disappeared near
Dubhe in the Plough. Surrounded by large double halo, oval in shape
(covering about 30 degrees, I suppose), as they disappeared from sight,
travelling quite fast and still in shape and formation."
There is a fine movie of the clouds and large halo recorded by Jonas Förste
of Jakobstad, Finland, available at www.spaceweather.com, together with a
selection of images of the event from locations all over Europe.
The Atlas V rocket carrying the Air Force's DMSP F-18 satellite lifted off
from Vandenburg AFB at 16:12 UT on 18 October 2009. Despite a foggy day,
the Atlas V flawlessly delivered the satellite to its assigned 838 km x 853
km orbit after an 18-minute flight. This mission marked the 600th launch of
an Atlas vehicle, carrying on a tradition that began with the first Atlas A
rocket launched from Cape Canaveral Air Force Station (CCAFS), Florida, in
1957. For the Atlas V, Sunday's success was the 18th for the program, with a
100 percent mission success rate. The inaugural launch for the latest Atlas
V configuration occurred from CCAFS on 2002 August 21.
Anyone who witnessed the Centaur fuel dump, or who has images or video of
the unusual clouds and/or halo is invited to send these to the undersigned
at docjohn@dircon.co.uk.
John W. Mason
19 October 2009
======================================================================
BAA electronic bulletins service. E-mail: circadmin@britastro.org
Bulletin transmitted on Mon Oct 19 19:17:38 BST 2009
(c) 2009 British Astronomical Association http://www.britastro.org/
======================================================================
BAA electronic bulletin No. 00444 http://www.britastro.org/
======================================================================
UNUSUAL ROCKET FUEL DUMP SIGHTED
A Centaur rocket caused a minor sensation on Sunday night, October 18, when
it flew over Europe and dumped a load of surplus propellant. On its second
orbit of Earth following launch earlier on Sunday afternoon, the Centaur
rocket had fired itself out of Earth orbit into a heliocentric orbit as it
travelled northwards over Europe shortly before 19:15 UT. A couple of
minutes later it began to dump surplus fuel, a process that continued for
around 13 minutes. This led to the appearance of an unusual, cloud-like
structure that was easily visible to the naked eye.
When first sighted from the UK, soon after 19:15 UT, the cloud of propellant
looked like a comet with a slightly fan-shaped tail travelling from south to
north. About 20 seconds later, a second object appeared. This was the US
military weather satellite (DMSP F-18), which the Centaur booster had helped
launch some three hours' earlier from Vandenberg Air Force Base (AFB) in
California. This was in turn followed by a quite remarkable large circular
halo which trailed the two previous objects in formation across the sky.
This large circular halo was probably an expanding puff of gas emitted
during an earlier firing of the Centaur.
The events were witnessed by John Fulcher from Cransford in Suffolk, who
described what he saw as follows:
".outside with telescope looking at various astronomical sights, looked up,
and saw an odd small cloud, but no cloud cover in sight, (sky) quite clear.
Then another, very similar, if not exact, cloud-like shape following on
behind, keeping formation. Tried to follow with telescope but travelling too
fast, so used binoculars, and followed them north to south; disappeared near
Dubhe in the Plough. Surrounded by large double halo, oval in shape
(covering about 30 degrees, I suppose), as they disappeared from sight,
travelling quite fast and still in shape and formation."
There is a fine movie of the clouds and large halo recorded by Jonas Förste
of Jakobstad, Finland, available at www.spaceweather.com, together with a
selection of images of the event from locations all over Europe.
The Atlas V rocket carrying the Air Force's DMSP F-18 satellite lifted off
from Vandenburg AFB at 16:12 UT on 18 October 2009. Despite a foggy day,
the Atlas V flawlessly delivered the satellite to its assigned 838 km x 853
km orbit after an 18-minute flight. This mission marked the 600th launch of
an Atlas vehicle, carrying on a tradition that began with the first Atlas A
rocket launched from Cape Canaveral Air Force Station (CCAFS), Florida, in
1957. For the Atlas V, Sunday's success was the 18th for the program, with a
100 percent mission success rate. The inaugural launch for the latest Atlas
V configuration occurred from CCAFS on 2002 August 21.
Anyone who witnessed the Centaur fuel dump, or who has images or video of
the unusual clouds and/or halo is invited to send these to the undersigned
at docjohn@dircon.co.uk.
John W. Mason
19 October 2009
======================================================================
BAA electronic bulletins service. E-mail: circadmin@britastro.org
Bulletin transmitted on Mon Oct 19 19:17:38 BST 2009
(c) 2009 British Astronomical Association http://www.britastro.org/
======================================================================
--
Good Clear Skies
--
Astrocomet
--
Colin James Watling
--
Astronomer and head of the Comet section for LYRA (Lowestoft and Great Yarmouth Regional Astronomers) also head of K.A.G (Kessingland Astronomy Group) and Navigator (Astrogator) of the Stars (Fieldwork)
--
Web: http://lyra.freewebsites.com/
Good Clear Skies
--
Astrocomet
--
Colin James Watling
--
Astronomer and head of the Comet section for LYRA (Lowestoft and Great Yarmouth Regional Astronomers) also head of K.A.G (Kessingland Astronomy Group) and Navigator (Astrogator) of the Stars (Fieldwork)
--
Web: http://lyra.freewebsites.com/
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