Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift. | | |
WEEKEND METEOR SHOWER: Earth is about to pass through a stream of debris from Halley's comet, source of the annual Orionid meteor shower. Forecasters expect the shower to peak on Saturday morning, Oct. 22nd, with more than 15 meteors per hour. Earth isn't the only world in the debris stream; NASA researchers will also be watching for meteoroid strikes on the Moon. [full story] [meteor radar]
SOLAR FLARE: This morning at 0325 UT, Earth-orbiting satellites detected an M1.6-class solar flare, the first significant eruption in days. Because the blast site was located on the sun's northwestern limb, the flare was not Earth-directed. Solar flare alerts: text, phone.
THE DECAY OF ROSAT: The doomed ROSAT X-ray space telescope continues to descend toward Earth. Multiple experts agree that re-entry should occur on Oct. 23rd, with most favoring the early hours of the day. Decay time uncertainties exceed 8 hours, so it is still impossible to say exactly where ROSAT will disintegrate.
Sky watchers say ROSAT is bright and easy to see, but photographers are having a hard time catching it. Dewey Vanderhoff tracked it over Cody, Wyoming, on Oct. 18th: "It was easily the fastest-moving satellite I have ever seen, being in such a low orbit and accelerating towards its doom. I barely got off a 'shotgun' 2-second exposure as ROSAT raced between Pegasus and Pisces (image)."
On Oct. 16th, astrophotographer Thierry Legault trained his 14-inch telescope on the observatory, and this is what he saw:
A video of the flyby may be found on Legault's web site. "The satellite looks very steady," he says, "there was no sign of tumbling or flares. Visually, ROSAT was crossing the sky so fast! I hope that it will give a nice fireworks over my place when it re-enters."
Until then, sky watchers should be alert for a fast-moving light in the night sky. To catch ROSAT, check Spaceweather's Satellite Tracker for local flyby times. You can also turn your smartphone into a field-tested ROSAT tracker.
UPDATE--ROSAT FLARES! Last night, multiple observers in California reported seeing a bright flash of light from ROSAT. "In addition to the satellite screaming thru the sky because of it's low altitude, it also displayed a short brilliant flare," says Derek Breit of Morgan Hill, CA. He caught the event in this 14 MB video:
Video credit: BREIT IDEAS Obs. Morgan Hill
"I must have seen the same flare Derek captured on the 0226Z ROSAT pass over Northern California," adds Kent Yeglin. "ROSAT was 3.2 seconds earlier than expected. The magnitude was around 0 with a short-duration flare to perhaps magnitude -6 to -8, comparable to brightest Iridiums. Flare peak was very short duration -- under a second -- more of a flash."