Thursday, February 19, 2009

Texas fireball leads to meteorite finds, other side effects

Several meteorites - one specimen already identified as a chondrite - have been recovered a few days after a spectacular daylight fireball was seen over Texas on February 15th. (Minutes after the event interesting radar echos had been detected high in the atmosphere, with the physical explanation less clear; there is also a report of a persistent smoke trail.) So this is an astronomy/planetary science story now - but it hadn't always been that way: While astronomically minded folks looking at the video of the fireball (also here from this source as well as here and here and on YouTube numerous times) immediately concluded that it had to be a meteor and not a satellite reentry, seemingly official claims that the sky show that something to do with the satellite collision five days earlier had momentarily confused even those who somehow knew it couldn't be - let alone the mass media often consulting the wrong 'experts'.

Even the New York Times spoke of a "mystery" with the "origin unknown" over a day after everything was clear! And Space.com carried only the wrong story for two days before having an update. The Texas fireball/meteorite dropper was thus also an interesting social study - and for the first hours it seems to have played out mainly on Twitter where it all started with this "news" tweet. Soon the story was all over the place, with a disturbing lack of "normal" news coverage - which followed eventually. News of what it really was had a hard time to percolate through the 'hive mind', though, and a day later "mystery" tales dominated the feeds.

Here's a sampling of the bewildered news stories to which a strange weather advisory and a mysterious NOTAM as well as a short-lived reentry scare in Canada certainly contributed, in roughly chronological order of their first publication (often they were then updated several times): AP, KEYE, WacoTrib, Fox, CNN, Houston Chr., My San Antonio, Dallas News, Star Telegram, Statesman and Bild, an iReport (using a file picture for illustration) and some other blog coverage (also here and here, where a blogger/reporter actually plotted the trajectory of the fireball). • Interestingly the Texas fireball was not the only one making news: Two days earlier there had been cases in Kentucky (more and an article) and Italy (the picture). • The first papers on the fresh Canadian meteorites of last year are out. • And a pioneer of NEO research has died already in January.

In other news the best viewing window for comet Lulin has begun: observations of Feb. 19 (more and also about a coma asymmetry), Feb. 18 (more), Feb. 17 (a spectacular animation from this site; also Slooh pictures first reported here), Feb. 16 (more; the comet was estimated at 5.3 mag. that day) and Feb. 15 (before that day the Moon was too bright and close), various observing reports, pictures on Flickr and many articles (more, more, more, more and more) plus a weird reaction by Lulin's discoverer ... • Comet 33P/Daniel underwent a small outburst and looked like this, but it's over. • Here is an impressive movie of the last penumbral lunar eclipse as seen from lunar orbit when the Earth rose with the Sun just emerging behind it!

• The more south you are the better these days: Today there was a Mercury/Mars/Jupiter trio visible in the morning sky from Oz where the new Jupiter season is beginning and one can see five planets during the night. • Saturn will experience a quadruple satellite transit on Feb. 24. • And Venus is brighter than ever and frequent UFO trigger now. • Did something strange happen to RX Lyrae last year as this picture may show? • CV V630 Cas may be acting up. • The 2nd Galaxy Zoo has been launched, with reports here, here, here, here, here and here. • Astrometry.net on Flickr is making news. • A 150° star trail panorama from India, a Milky Way panorama from Mauna Kea, the zodiacal light from Tenerife, the coolest-looking observatories on Earth - and this blog and the related Twitter feed being hailed in the context of the Texas fireball, als is the Twitter feed here!

Thursday, February 12, 2009

Penumbral eclipse was evident - when weather, longitude were right

You could do it like in Turkey where they arranged lunar watching parties on the evening of Feb. 9th to celebrate the eclipse after it was over - but it surely was more fun much farther East when the penumbral lunar eclipse could actually be seen and was pretty obvious: Here are good pictures from Oz and more, reports from the Philippines (with pictures), Australia and India (another and another report). The eclipse was also used for a StarPeace event on the Indian-Pakistan border; when the full Moon rose in Europe, the eclipse was over, of course. Here is that moonrise with an omega effect, i.e. an inferior mirage. • Yet more great pictures of the annular solar eclipse from Indonesia have become available - and here you can download a perfect view of the 2nd contact (by the same photographer) with a few Baily's Beads! • While here a connection between the Israeli elections and total eclipses is made ...

In other news comet Lulin is hard to observe right now because of the waning Moon nearby, but when it peaks around 5th mag., it'll be in the dark again (and visible in the full 2nd half of the night): pictures of Feb. 11 and Feb. 9 (processed) and visual observations up to Feb. 7; also discussion of Lulin's plasma tail. The NASA talk about an in principle poisonous gas in Lulins coma has led to some unfortunate headlines, also in Germany (where this tabloid headline says "green poison comet races by Earth" ...). The comet's appearance has also been linked to the IYA. • Feb. 3 images of 116P and 29P.

• Here now an amateur detection of Saturn's E ring (some of the ring gaps have new names, by the way) and the moon Calypso, an observation of Dione in eclipse under the rings and a Titan transit on Feb. 8. • One may also wonder why Venus is so bright. • There is a Nova in the LMC. • The debris from the big satellite collision on Feb. 10 (see the Cosmic Mirror #325 for many links) is detectable by radar echos. • What is 1999 RQ36 up to? (Not much for now.) • Also NASA's SkyView, 35 stunnung hi-res public domain astro pics and 101 breathtaking near-IR landscape pics of this planet - where it's happy Darwin Day (nice drawing) today!

Saturday, February 7, 2009

Lulin's ion tail excites astrophotographers - and first naked-eye sightings around 6,0 mag.

Just before the Moon began to spoil the view for the next 10 days or so, the comet Lulin show really got exciting: its faint ion tail, which has reached some 2° in length, is experiencing fast and complex effects in the solar wind confusing inexperienced observers (though perfectly normal, which includes a major disconnection event on Feb. 4) while the comet's coma - now estimated around 6,0 mag. - has been sighted occasionally with the naked eye in recent days, e.g. in Texas and India. The picture collections like this, this and this are growing; here are selected images and reports from Feb. 7 (pic, vis), Feb. 6 (pic w/long tail, pic, vis, vis), Feb. 5 (pic at Alpha Librae, pic from here, pic, pic, pics, widefield pic, vis), Feb. 4 (pics with the with DE, dito and Feb. 4 vs. Jan. 31 pics), Feb. 3 (pics, pic, pic, vis w/naked-eye averted), Feb. 2 (pic w/tail effects, pic, widfield pic at dawn) and Feb. 1 (pic, pic, pic described here) plus more Lulin articles here, here, here, here and here. • More interesting comet pictures show 77P "facing" two galaxies and 144P in the Hyades on Feb. 2 and Jan. 31, described here.

In other news there will be a transit of Titan on Saturn's disk in the night Feb. 8/9 visible e.g. in Oz; here is an animation of an earlier such event, also seen from down under. Meanwhile the rings have opened a bit again as beautiful images from Feb. 4 (another one, explained here) and Feb. 3 (another one; no data) show. And an amateur has used the almost edge-on view to image Calypso, a small satellite of Saturn! • Amateurs were also involved in observations of a stellar occultaton by Titania of Uranus long ago. • And bright evening "star" Venus is causing UFO alerts around the world. • The penumbral lunar eclipse on Feb. 9/10 following the annular spectacular will mainly be an Asian/Oceanian event with nothing to see e.g. in Germany where it's being discussed nonetheless. So how about Clavius at 200 m/pxl?! • Several asteroid sizes have been measured by optical interferometry while a new PHA isn't exactly hazardous: According to the first orbit it has a mere impact probability of < 1 in 100 million in 2046.

• Here is a Call for Monitoring for a planetary transit of HD 80606 which has been much in the news lately: Around Valentine's Day it could experience a long primary eclipse. Meanwhile the lightcurve of Eta Carinae is doing interesting things. • Brilliant aurora images from Tromso have been published; this one is particularly stunning. And a weird distorted moonrise was imaged recently - the animation is particularly stunning. • Here is a portrait of satellite watchers, a species of amateur astronomers also known for hi-res pics of the ISS in front of or next to the Moon or even transiting Venus. Or just passing by, a frequent view. • Finally, the Chambliss Award for Amateur Achievement for 2008 has been awarded to Steve Mandel, a new sensor material could revolutionize CCD chips - and here is a great collection of digital space art, in case the real Universe isn't enough. :-)

Sunday, February 1, 2009

More fascinating solar eclipse pics, stories - while February just has a penumbral lunar one

There has been a lot more coming in from the annular solar eclipse of 26 January or from its partial manifestation away from the narrow antumbral track - although the picture shown in this DLR press release does not show the latter but, as a comparision with this NASA image release reveals, the umbra of the 2006 total eclipse. A Google search for ISS images of the antumbra of 2009 came up empty, so it's not clear whether it was photographed at all. Back on the ground this collection at Bosscha Obs. has some of the best annularity views from Indonesia. There are also an interesting report from Indonesian TV (no annularity, though), some pictures and a video from Anyer, a report from Indonesia (followup) and another one. (These Indonesian stories brought back intense memories to this blogger who experienced his first total solar eclipse in this beautiful country 25½ years ago; reports from other 1983 trips are here, here, here, here and here. Sigh ...)

From partial zone we have yet another Manila sunset and partial phases from Thailand (also with a bird and at sunset, also here, and lots more pics), Sri Lanka and Mauritius. This eclipse was the first somewhat unusual sky event of the International Year of Astronomy and so the connection was made in South Africa (where some eclipse fashion was on display), Sri Lanka (more pictures) and Australia. Finally, here are 19 big and 66 small wire service pics - which showed up, uncredited, in many private websites ... Legally more sound, here are a big (German) review of the event and its new media impact plus a crappy German TV preview. All eyes are already on the next - total - eclipse (which will be a logistical nightmare for Japan), while still new videos of the last TSE turn up (the 2nd one is pretty funny; it happens at 1:04). February, meanwhile, will just serve us the least impressive of all eclipses, a penumbral lunar case. The month - some previews here, here, here, here and hier - will bring:
  • Feb. 9: Penumbral lunar eclipse, visible mainly in Asia and the Western U.S.

  • Feb. 16 til March 3 (in particular Feb. 19 til 28): Best viewing window for comet Lulin - brightest and no Moon.

  • Feb. 17: The Dawn spacecraft flies by Mars, will take some pictures for calibration purposes.

  • Feb. 17: Mars and Jupiter only 0.8° apart in the morning sky.

  • Feb. 19 or 20: Venus reaches largest brilliance, -4.6 to -4,8 mag.

  • Feb. 22 and 23: Moon close to Mars, Jupiter and Mercury.

  • Feb. 23/24: Lulin (moderately) close to Saturn.

  • Feb. 24: Mercury, Mars & Jupiter closest together, in a 4° circle at dawn.

  • Feb. 25: Ceres in opposition, should reach 6.9 mag.

  • Feb. 27: Closer Venus-Moon conjunction than in January.

  • Feb. 28: Lulin close to Regulus.
A good - but inconvenient - viewing window for comet Lulin (in the hours before dawn) is now underway, surely the best comet in February: The picture collections are growing and visual brightness estimates - still the best method for overall activity judgement - put it at ~6.5 in late January/Feb. 1st. Here are a visual observation of Feb. 1, a visual report by its discoverer and a mosaic of Jan. 31, a highly processed picture (from here), an animation and another discoverer's observation (his first visual ever) of Jan. 30, a drawing of Jan. 28, a visual obs. of Jan. 27, a picture and another one of Jan. 26, a picture & report of Jan. 24, a drawing and another one of Jan. 23 and a picture of Jan. 21. Meanwhile the science media have woken up, with more or less long articles here, here, here and here. • More comet pictures: 29P on Jan. 29, 28, 26, 25, 23 and 22, 144P on Jan. 26 and 25 (at the Hyades!), 67P on Jan. 29 and 25 and 116P (more), 17P, 19P and C/2006 OF2. • From the famous bolide of Jan. 17 little more has been heard.

Views of the Moon passing Venus have been widely appreciated (and caused some UFO alarm in Germany): the situation on Jan. 31 in Germany (more), on Jan. 30 in the U.S., Germany (more, still more, earlier, still earlier and in full daylight), from India (two more in the stream and another one) and Australia plus more and on Jan. 29 from Hawaii, Canada (more in the stream), the U.S. (more) and Germany (more), Norway and Italy in daylight. • An amateur photometrist has already detected dozens of exoplanets in transit. • R CrB has been below 14 mag. since November. • The Sun's still inactive but that's good in general. • Here are some fine ISS close-ups from the end of January. • A weird halo has been seen in the Czech Republic. • And true atmospheric optics aficionados see similar phenomena in the kitchen, too. :-)