Chances for Skywatchers to Spot Private Rocket Are Slim
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SpaceX's debut Falcon 9 rocket soars into space on its maiden flight during a June 4, 2010 test launch. CREDIT: ChrisThompson/SpaceX |
With the recent
successful launch of a new private rocket, called Falcon 9, and a space capsule
mock-up from Florida?s Cape Canaveral Air Station, some skywatchers
might be wondering if it will be consistently visible from the ground like many
other bright artificial satellites. The answer, apparently, is no.
That determination
comes from some of the die-hard satellite observers, who just last month were
able to locate and then track the U.S. Air Force's secret
X-37B space plane.
Observers from around
the world have since been able to get views of the X-37B as it moved across the
twilight sky with the brightness of a moderately bright star. That vehicle
is orbiting approximately 250 statute miles (402 km) above Earth, inclined 40
degrees to the Earth?s equator.
But catching a
glimpse of the Falcon
9 rocket, which launched Friday from Florida, is more
difficult, in part due to a much lower orbital altitude of 155 statute miles
(250 km), as well as a lower orbital inclination of 34.5 degrees. These two
factors restrict visibility to a much smaller area. [Spotting
spaceships from Earth.]
However, the Falcon 9
rocket built by the California-based company Space Exploration Technologies
(SpaceX) may have had one last hurrah following its successful maiden launch
last week. Before fading into the background of space, the rocket likely was
responsible for a short-lived ? but dazzling ? spiral of light seen over parts
of Australia that spawned a flurry
of UFO reports, according to Australian news reports.
"I
heard people in Australia thought UFOs were visiting :)," SpaceX's millionaire
founder Elon Musk told SPACE.com in an e-mail. "The venting of
propellants, which is done to ensure that an overpressure event doesn't produce
orbital debris, created a temporary halo caught the sun at just the right angle
for a great view from Australia. I thought the pictures looked really
cool."
Viewing Circumstances
Poor
The
less-than-optimistic assessment comes from members of SeeSat-L,
the online mailing list for visual satellite observers around
the world.
Kevin Fetter, a SeeSat-L member from Brockville, Ontario notes that, ?As for seeing it, the conditions are bad. It was placed
into a orbit, with a low orbital height. The orbital
inclination is only 34 degrees, so a lot of people are out of luck.?
Ted Molczan, the SeeSat-L Moderator
concurs with Fetter, adding that even limited visibility of Falcon 9 is now
compromised by the fact that for the next couple of weeks Falcon 9 will be
making passes during the daytime and hence will be unobservable.
?A quick check of current visibility north of the equator,
reveals the tail end of evening visibility at latitudes south of about 30 N; no
visibility further north," noted Molczan.
"Morning window opens in a couple of weeks. South of the equator, around
35 S, has tail end (several days) of morning
visibility.?
Was
likely Australian UFO
But
as obscure as Falcon 9 has been for even experienced satellite watchers to see,
it likely was responsible for a rash of UFO reports on Saturday morning over New South Wales,
Queensland and the Australian Capital Territory of Canberra.
A strange
spiral cloud with a yellowish-green tint suddenly appeared in the predawn sky.
Some described it as a "lollipop-type swirl," according to the
Australian Broadcasting Corp. Others say it hovered for a while before
gradually moving in an eastern direction until it was out of sight.
One eyewitness
described it having a "?distinct bright centre, much like a bright star,
indicating an object shedding light trails, spiraling and fattening out from
it.? Many commented that the effect lasted only two or three minutes before it
descended quickly out of view.
But Molczan believes that what the Australians saw was in
reality, Falcon 9.
?The Falcon 9 test payload (?Dragon?), which is attached to
the rocket's 2nd stage), appears to account for the phenomenon. (The UFO
sightings) occurred about 65 min. after launch, so
perhaps the 2nd stage was dumping excess propellant. Similar actions by Centaur
stages have always resulted in spectacular cloud-like formations,? Molczan wrote.
A
similar
sight was widely visible from parts of North America back in 2004, as well
as over Norway and Russia in December 2009. A Russian Bulava
missile caused that December event.
- Gallery
- Liftoff! SpaceX's Falcon 9 Rocket First Launch
- 'UFO'
Spotted Over Australia Likely a Private Rocket
- Telescopes
for Beginners
Joe Rao serves as an
instructor and guest lecturer at New York's Hayden Planetarium. He writes about
astronomy for The New York Times and other publications, and he is also an
on-camera meteorologist for News 12 Westchester, New York. SPACE.com Managing
Editor Tariq Malik contributed to this report.











