Further thoughts on fireballs, asteroids and coincidence

Fragments said to be from the Russian meteorite fall ring the hole in Chebarkul Lake. Credit: Reuters: Chelyabinsk region Interior Ministry

Asteroid 2012 DA14 has moved on, and the Russians are busy cleaning up the mess from yesterday’s fireball. Hopefully a few people are also busy looking for meteorites from the fall. The only meteorite-maybes I’ve seen photos of are the small, black rocks found around the perimeter of the hole in Chebarkul Lake, west of Chelybinsk.

A Tagish Lake meteorite fragment. Credit: Michael Holly, Creative Services, University of Alberta.

If these are indeed meteorites from the bolide, they remind me of the black, carbonaceous debris dropped by the Tagish Lake fall over the Tagish Lake area in British Columbia on January 18, 2000. Carbonaceous chondrites are fragile, carbon-rich meteorites that easily shatter into dust and small bits during a fall. If that’s what we’re dealing with here, meteorite hunters better get cracking – this type erodes quickly. Divers found no trace of any meteorites in the lake at the bottom of the hole today.

It is odd though that two days have gone by without a single significant fragment found. Meteorites, which develop a black fusion crust on atmospheric entry, would show up beautifully against the snowy Russian landscape. So what gives? How long will see purported Chelyabinsk “meteorites”pop up on eBay before the real item finally shows? Only hours after the fall, the first dubious specimens appeared on the auction site. Not a one of them looks like a fresh fall and some are clearly not meteorites. Buyer beware!

These MET-7 satellite photos clearly show the Russian fireball traveling from east to west. North is at top. Asteroid DA14′s trajectory was south to north or nearly perpendicular to the fireball’s. Click for more information and a short video. Credit and copyright: EUMETSAT

As for the Russian fireball being related in any way to the asteroid flyby, it is not. I’ve been in touch with folks who orbits and it’s becoming even clearer that we’re dealing with two very different asteroids. Not only were their orbits nearly perpendicular to each other from the perspective of the Earth, but it’s not possible for a cloud of DA14 fragments to even reach the city of Chelyabinsk at 55 degrees north latitude in Russia.

Since the fragments would approach Earth from due south nearly parallel to the planet’s axis, if they hit the planet, they’d strike the southern hemisphere. From the fragments’ very-close-to-Earth perspective, Chelyabinsk, Russia is on the far or opposite side of the globe and totally out of sight. Amateur asteroid discoverer Dr. Marco Langbroek uses this analogy and I paraphrase slightly:

“Compare it with a car. A bird flying toward your car will always hit the front of the car – it cannot hit the back of the car. Chelyabinsk at 55 North latitude is “the back of the car” in this comparison, given the approach direction of 2012 DA 14 and any fragments of it.”

We place a lot of faith in coincidence because, well, if you drop a plate, it breaks. The two are related. So if two close meteors or asteroids appear around the same time, many of us make the assumption they’re related too. It totally makes sense to wonder about a connection between the two events, but once the data is in, we need to take another look at our surmise. Speaking of data, we’re still waiting on radar images from the Goldstone antenna. As soon as they’re available, you’ll see them here.

Animation of DA14 made from images taken this morning from New Mexico. Credit: Ernesto Guido and Nick Howes

I’m curious if any of you got to see the asteroid flyby either through binoculars or telescope. If so, we’d love to hear your story. Clouds were cruel here in Duluth, Minn., but I stood at the telescope and waited. And waited. Finally, a few thin openings passed the asteroid’s location just above the bowl of the Little Dipper about 7:15 p.m. (CST). There was just enough time to identify DA14 and watch it scoot north. One minute of joy followed by hours of clouds.

Cosmic debris rains down through the atmosphere nearly every day, accumulating at a rate of 37,000 to 78,000 tons per year. While that may sound like a lot, much of it is dust or passes unseen over the oceans.

At least a half-dozen times a year, however, a fireball burns up over a populated area and drops meteorites. Their fall is pinpointed by careful analysis of the angle of entry based on eyewitness reports, Doppler weather radar, security cameras or even dashboard cams, as we saw in Russia on Friday. Once the word is out, everyone from those closest to the areas of impact to meteorite hunters from across the planet are eager to find a piece of otherworldly treasure. The Chelyabinsk region has been pretty much off-limits to foreigners until recently, so it should be interesting to see who gets in and out without being arrested.

What they’re looking for are leftover fragments from collisions of bodies in the asteroid belt between Mars and Jupiter. Over the eons, Jupiter’s gravity nudges the shattered rocks out of the belt, sending them toward the inner solar system. Millions of years later, those fragments may hurl toward Earth. As the space rocks plummet through the atmosphere, the heat and pressure become so intense that even a fairly large object, say 13 to 50 feet across, will more often than not burst into harmless pieces that fall to the ground as meteorites.


The famous Peekskill fireball of October 9, 1992 that dropped a meteorite that smashed the rear end of a Chevy Malibu

A 13-footer hits our planet about once a year. One the size of Friday’s fall in Russia — about 50 feet across and weighing about 7,000 tons — strikes Earth about once every 50-60 years. The bigger they are, the less frequently they fall but the greater the consequences.

Yesterday’s flyby asteroid 2012 DA14, a rock about 150 feet across, would have caused regional devastation had it struck in one piece. One that size only rings our bell every thousand years. An asteroid of about 0.9 miles across could cause planet-wide devastation and climate change. The good news is such an event happens only once in half a million years.

While most of the 0.9-mile and larger near-Earth asteroids have been discovered, there are something like a million others as big as the one that zoomed by harmlessly yesterday. Sky surveys have ferreted out many of them, but many more remain to be found — before they find us. While there are many great ideas about how we might deflect an asteroid headed toward Earth, there are presently no programs underway to accomplish that goal.

Watch asteroid 2012 DA14 flyby LIVE on the Web

2012 DA14 earlier this morning seen from Australia. The negative or reversed image is a 4-minute time exposure. The fast-moving asteroid created a trail of light during that time. Credit: Dave Herald

After this morning’s Russian fireball, we’re all sitting on the edge of our seats, but the fireball and 2012 DA14 are unrelated asteroid fragments on very different paths. One made a beeline directly to Earth, the other will safely pass 17,150 miles away around 1:24 p.m. (CST) today. The latest estimates on the Russian meteoroid’s size before it broke it up in the atmosphere put it around 50 feet across with a weight upwards of 7,000 tons. Today’s asteroid in contrast is about 150 feet end-to-end and tips the scales at 209,000 tons.

Amateur astronomer Dave Herald of Australia has been busy taking pictures of 2012 DA14 through his telescope overnight. His photograph shows the asteroid as a trail against the starry backdrop as it moved northward during the 4-minute time exposure. Herald will be providing an online feed with his observations and photos for NASA later today.

Simulated image of 2012 DA14 approaching Earth this morning around 9:15 a.m. CST. Antarctica shows up nicely as the asteroid closes in. Click to see the latest image.

If you’d like to hear commentary and see real-time pictures of the flyby (from Dave and others), check out NASA TV’s live stream beginning at 11 a.m. Central Time and continuing through the afternoon. Undoubtedly you’ll learn more about the Russian fireball there, too. When pictures are shown, the asteroid will look exactly like a star, because you’re looking at a small object many thousands of miles away.

A Ustream feed of the flyby from a telescope at NASA’s Marshall Space Flight Center in Huntsville, Ala., will be streamed for three hours starting at 8 p.m. CST this evening when the asteroid is visible in a dark sky over the U.S. You can view the feed and ask researchers questions about the flyby via Twitter HERE.

And don’t forget to take a virtual ride-along with the asteroid available HERE. Images are updated every 2 minutes. Enjoy the show!

Must-see videos of spectacular Friday fireball over Russia


Video of a brilliant fireball over Russia on Feb. 15, 2013 local time

A spectacular fireball exploded over the Russian city of Chelyabinsk more than 900 miles east of Moscow around 9:26 p.m. (CST) Feb. 14 or 9:26 a.m. Feb. 15 local time in Russia this morning.

Frame grab from the video during the early phase as the fireball rapidly brightened

Frame from a few seconds later as the meteor heads toward the horizon

The dashcam videos record one of the most brilliant and amazing fireballs I’ve ever seen. Watch as it becomes nearly as bright as the sun with a strong reflection off the roadway. Loud booms accompanied the spectacle and glass windows were shattered. There are reports of downed power lines and interrupted cell phone service. Some 500 people were treated for injuries, mostly from broken glass sent flying from the shock wave and sonic boom. The roof at a zinc factory in Chelyabinsk may have collapsed from the same.


Video from a different dashcam taken from a different location where the fireball is higher in the sky and approaching at a different angle with an insanely spectacular trail. Click to view.

In the second video, notice how long the smoke trail lasts as the car speeds along in a big hurry to get somewhere. In case you’re wondering, this is not related to the flyby of asteroid 2012 DA14 expected around 1:24 p.m. CST today. One clue is the direction of travel. Had it been “leading” today’s asteroid, the fireball’s path would have been almost directly south to north. Instead it traveled from northeast to southwest.

But they do have one thing in common. Even though one will miss Earth and the other’s trajectory took it straight into our atmosphere, both are small asteroids almost certainly originating from the asteroid belt between Mars and Jupiter.

A hole in Chebarkul Lake, west of Chelybinsk, made by meteorite debris. Small fragments of black rocks were found around the crater. Two other impact sites are reported. Click for more photos and further story. Photo by Chebarkul town head Andrey Orlov.


Great video of the smoke trail also called a meteor train 

In this photo provided by Chelyabinsk.ru, a meteorite contrail is seen over Chelyabinsk on Friday, Feb. 15, 2013. The meteor, which streaked across Russia’s Ural Mts. Friday morning, was the largest reported fireball since the 1908 Tunguska explosion. Credit: AP Photo/Chelyabinsk.ru

The latest estimate of size for the original meteoroid – the name given to the object while still in space before entry into Earth’s atmosphere – is about 50 feet across with an approximate weight of 7,000 tones. The Russian Academy of Sciences released a statement saying the meteor traveled at 33,000 mph and shattered about 18-32 miles above the  ground. Three impact sites are now reported including one that fell through the ice in Chebarkul Lake. Dark, rocky meteorites have also been found.


Short video showing dramatic effect of the shockwave

I’ll be updating this blog with more information and photos throughout the day.

More videos HERE.

Go for a virtual asteroid ride; seismic activity on 2012 DA14?

Asteroid 2012 DA14, which will pass about 17,200 miles from Earth tomorrow (Fri. Feb. 15) around 1:24 p.m. CST is about 150 feet long or somewhat less than half the length of a football field. Illustration: Bob King using wiki and NASA images

As asteroid 2012 DA14 silently flies toward Earth, how would you like to go along for the ride? Now you can, virtually speaking. NASA has created a simulated display that allows you to accompany the asteroid as it speeds toward the planet. Since the view refreshes every two minutes, you can watch the planet grow larger as the asteroid sweeps in to make its closest approach tomorrow around 1:24 p.m. Central Time. That’s when the real drama will unfold as 2012 DA14 passes just 17,200 miles over Indonesia before speeding back into the depths of space. Click HERE to make the trip.

Although 2012 DA14 won’t impact Earth, the planet’s gravity will leave a potentially strong impression on the asteroid. Besides bending its orbit into a smaller circle with a shorter orbital period during the flyby, it’s possible that the space rock might tremble with tremors or asteroid-quakes.

View from the virtual asteroid tracker looking toward Earth today Feb. 14, 2013 at 1:37 p.m., one day before closest approach. Credit: NASA

“We are going to be looking closely for evidence of seismic activity on 2014 DA14 as it passes by,” says Richard Binzel, a professor of planetary science at MIT. “This is the first case of an object coming close enough to experience quakes AND where we have enough notice to plan observations.”

The Galileo spacecraft captured this “stretched color” view of asteroid 951 Gaspra in 1991. The red color is caused by solar radiation and cosmic rays weathering of the asteroid’s soil. Credit: NASA

A few years ago Binzel noticed a small group of asteroids that didn’t show signs of “space weathering” from bombardment by cosmic rays and solar radiation over the eons. High-energy particles interact with asteroids’ rocky surfaces and cause their soils to turn dark-red.

After studying their orbits, he discovered that all these “fresh-faced” space rocks had had close encounters with the Earth in the past million years.

“We believe they were ‘shaken up’ by their encounters with Earth,” he says. “Gravitational forces during the flybys can stretch, rattle, and torque these asteroids, causing dark, space-weathered material on the surface to be overturned, revealing the fresh stuff underneath.”

NASA’s Goldstone radar dish in California will have its eye trained on the asteroid during tomorrow’s flyby. The dish sends radio waves at the asteroid and measures their echo or reflection upon return to build up a map of its shape. Credit: NASA

2012 DA14′s crust could shift by an inch or two and possibly release a puff of asteroid dust. MIT postdoc Nick Moskovitz, who works with Binzel, is coordinating observations with worldwide observatories to pin down the color, spin, shape, and reflectivity of the asteroid as it passes by. NASA’s 70-meter Goldstone radar dish will also repeatedly ping 2012 DA14 with radio waves and measure the energy reflected back to create a 3D picture of it. If we’re very fortunate, the dish might even see the effects of seismic activity. Read more on the topic HERE.


Nice video about the flyby from NASA’s ScienceCast

Photo of incoming space rock 2012 DA14; check out a cool asteroid widget

2012 DA14 is the tiny black dot between tick marks in this reversed (negative) image. It passed near the globular cluster 47 Tucanae (below) this morning Feb. 13, 2013. The picture is a stack of 12 x 1-min exposures. The stars are trailed because the telescope tracked the asteroid. Credit: Dave Herald

Congratulations to amateur astronomer Dave Herald of Murrumbateman, Australia! He snapped one of the first images of incoming asteroid 2012 DA14 this morning as it passed through the halo of the rich globular cluster 47 Tucanae. At the time, the 150-foot-long rock was 744,000 miles from Earth and a very dim magnitude 18.4.

With Friday’s visit by 2012 DA14 swiftly approaching, what better time than now to get an asteroid widget? NASA’s Jet Propulsion Lab has created a widget that helps you keep track of asteroids that are making close approaches to our planet. Called Asteroid Watch, it tracks both near-Earth asteroids and comets.

JPL’s Asteroid Watch widget

Asteroid Watch displays the date of closest approach, approximate object diameter and distance from Earth for each flyby. The object’s name is displayed by hovering your cursor over its encounter date. Clicking on the encounter date will display a Web page with details about that object.

The Widget displays the next five Earth approaches to within 4.6 million miles (19.5 times the distance to the moon). An object larger than about 150 meters (492 feet) that can approach the Earth to within this distance is termed a potentially hazardous object or PHA.

The Mac version runs on OS 10.4 or later, while the PC / Mac version works on computers with Yahoo! Widgets installed. Go HERE to get either version along with setup instructions. Once downloaded and opened, look for it the Mac version on your dashboard. The hovering feature works well and the asteroids are current. There’s even a little arrow link on the bottom you can click on for the full list of upcoming close approaches.

I’ve not been able to test out the PC version, but have learned that it may not update like the Mac version does. Check it out and let us know what you find. If it doesn’t work as expected, not to worry. Just visit and bookmark NASA’s Near-Earth Close Approaches table, which shows a complete listing of recent and upcoming close asteroid flybys. There 16  of them coming up in the next two weeks. Do we live in a cosmic shooting gallery or what?

Return of the “Pink” Planet

This map shows the sky from mid-northern latitudes facing west about a half hour after sunset tonight Feb. 12, 2013. Mercury lies about “two fists” below the moon in bright twilight. Fainter Mars is a few degrees below Mercury. Created with Stellarium

Don’t look now, but there’s a new planet creeping up from the western horizon. Mercury makes a special guest appearance at dusk for the next week or so. Tonight the moon can help you find this elusive planet. What makes it a hard catch? Well, it never strays far from the sun, appropriate behavior given that Mercury is, after all, the innermost of the eight planets. Typically it stands just two fists held at arm’s length above the horizon after sundown. If trees or buildings get in the way, you won’t even notice it.

Tonight it shines brighter than Rigil in Orion and nearly matches Canopus, the second brightest star in the entire sky. But you’d never know it. Trapped near the horizon, the little planet must compete against the orange glow of dusk and the greater thickness of air there.

Mercury (top) and fainter Mars shine together at dusk as seen from the Gulf of Trieste along the Adriatic Sea on Feb. 10, 2013. The photo nicely captures their naked eye appearance. Credit: Giorgio Rizzarelli

As we know from personal experience, the sun’s light is more tolerable near sunrise and sunset. Likewise, the rising moon is considerably fainter than one seen overhead. Dust and air molecules absorb and scatter light, especially when we direct our gaze horizon-ward where the air, water vapor and dust are thickest. Astronomers call this phenomenon atmospheric extinction. It’s the reason they wait for stars to get high enough to clear the thickest air before gathering data.

By the time Mercury becomes visible a half hour to 45 minutes after sunset, air and dust have dimmed it by more than a magnitude, making it similar to Betelgeuse in brightness. If all this talk of extinction makes you pessimistic about seeing the planet, I apologize. Mercury’s not hard to spot if you’ve got haze-free skies and an unobstructed western horizon. Don’t be afraid to cheat a little with binoculars. I sometimes use them to find a twilight planet early so I know better where to look once the sky gets darker.

Mercury photographed by NASA’s MESSENGER spacecraft. The generally gray globe is mostly blanketed by volcanic rocks. Credit: NASA

If you want a real twilight challenge, try finding Mars below Mercury. It’s not only fainter but being lower, even more of its light is sucked up by the air. Binoculars are essential for this one.

As a kid I always thought Mercury was a red-hued world and saw it that way whenever it would make one of its twilight appearances. Truth is, the planet is quite gray, much like Earth’s moon. Photographs from the MESSENGER spacecraft show a surface covered in ancient volcanic rocks. Only later did I realize that my pink planet gathered it color from the very twilight itself. What color does it look to you?

How to find and follow asteroid 2012 DA14 during Friday’s flyby

Get ready for Friday’s flyby of the 150-long rocky asteroid 2012 DA14. Credit: NASA/JPL-Caltech

Near-Earth asteroid 2012 DA14 has become a sizzling topic online and on the TV news. Not a week goes by lately when I don’t hear about “the asteroid that’s going to fly by Earth”. Yesterday John, my mailman, asked me about it.

“Supposed to be half as long as a football field,” he offered. John was right. It’s a good-sized rock – the largest we know of to approach Earth this closely.

It’s fun that folks are excited about this 150-foot long solar system vagabond. I only wish we’d all have a chance to see it. Using the charts and tips below, it’s my hope that many of you will.

2012 DA14 was discovered by astronomers in the La Sagra Sky Survey program in Spain in February 2012. With an orbital period (time it takes to go around the sun) of about 368 days it makes annual spins by Earth. Friday’s flyby will be the closest the asteroid has been for many years and the closest it will come for at least the next 30.

And we do mean close. On Feb. 15 at about 1:24 p.m. (CST), 2012 DA14 will zoom 17,200 miles above the Earth’s surface traveling at 17,400 mph. While this is a record approach for a known object of this size, other smaller asteroids have skimmed nearer yet.

We only have to look back to June 27, 2011 when 2011 MD, about 20-50 feet wide, passed just 7,500 miles overhead. No harm came to Earth’s nail-biting residents then and none will during Friday’s pass. The record by the way for the closest-known shave goes to the petite, 3-foot-long 2011 CQ1 at 3,400 miles on Feb. 4, 2011.

2012 DA14 will briefly fly between the geostationary belt of communications satellites (white dots) and the Earth during closest approach Friday Feb. 15. Notice how it comes from under the Earth, moving from south to north. Credit: Simone Corbellini

On average, we’d expect an object of 2012 DA 14′s size to get this close to the Earth about once every 40 years. An actual collision by something this big is far rarer – about once every 1200 years.

On its inbound leg, 2012 DA14 will buzz between the constellation of GPS satellites, which orbit at about 12,600 miles, and the ring of geostationary satellites located about 22,200 miles above Earth’s equator. None will be in danger because the asteroid will come up from below and pass through the empty zone between the two.

Some 300 active weather and communications satellites are parked in orbit in the ring and relay communications around the globe. When your favorite TV weatherperson flashes pictures of storms and hurricanes taken from space, you can bet it was photographed and transmitted back to Earth by a geostationary satellite. There are presently about 32 GPS satellites used by government and consumers alike to pinpoint precise locations on the ground.

Simulation of the original constellation of 24 GPS satellites orbiting Earth. Credit: Wikipedia

As the asteroid zips by, Earth’s gravity will bend its orbit, changing its orbital period from 368 to 317 days and making close approaches like this one less likely. As for 2012 DA14 striking any satellite at all, Donald Yeomans, head of NASA’s Near Earth Object Program Office at the Jet Propulsion Laboratory, says it’s “extremely remote.” Given the huge volume of space the asteroid must pass through as it swings by Earth and the tiny number of potential targets, we might liken it to a gnat in a mansion.

Despite its proximity, 2012 DA14′s tiny size means not even the largest telescopes will show it as more than a star-like point of light. If you live in eastern Europe, Asia or Australia, you’ll see the asteroid at its closest, when it not only be brightest but moving fastest. I’ve seen a few Earth-approaching asteroids, and they really can book across the sky, but few travel as fast as this one will. In just three hours centered on closest approach, 2012 DA14 will zip from the Southern Cross all the way to the Bowl of the Big Dipper!

World map with time zones. The area inside the red circle shows very approximately where the asteroid will be visible in a dark sky when it’s closest and brightest. Map credit: Wikipedia

It reaches peak brightness around 1:24 p.m. (CST) or 7:30 p.m. in London, England. While the sky will be dark there at that time, the asteroid will still not have risen in the east. We have to go travel farther east and south to catch it at its brightest. Let’s pick Athens, Greece. There the the sky will be dark early enough to spot the asteroid at its brightest (magnitude 7.4) low in Virgo around 10 p.m. local time using standard 40-50mm binoculars. Observers should look for a dim “star” slowly moving from south to north in the field of view.

A map from Heavens Above showing the entire sky from Jakarta, Indonesia. The labeled arc is the asteroid’s path during the night. Credit: Chris Peat

As we continue moving east across the globe, 2012 DA14 gets higher and higher in a dark sky. If you sense the eastern hemisphere has the best seats in the house, you’re right.

Residents of Jakarta, Indonesia for example will see the whole show from beginning to end. Fortunate sky watchers there can spot 2012 DA14 with a telescope around 1 a.m. Saturday morning Feb. 16 (local time) near the Southern Cross.

By 3 a.m. they can switch over to binoculars to catch it at maximum brightness.  At dawn, the asteroid will have made a complete south-to-north beeline from Cross to Dipper and once again require a telescope to see. What a way to spend a night out, eh?

Did I say it was moving quickly? When nearest Earth, 2012 DA14 will hurry along at 1 degree or two full moon diameters per minute. Not only will you need binoculars, you’ll also need to know exactly where to look. By the time the sky is dark across the U.S., South America and Canada Friday night, the asteroid will have slowed considerably and faded to around magnitude 11.5 -12.

Sadly, U.S. sky watchers will need a 6-inch or larger telescope to find and follow it. The good news is that the asteroid will be conveniently placed in the northern sky near the Little Dipper.

The asteroid is shown at three times for an observer in Athens, Greece Friday evening facing east around 9:45 p.m. local time. 1 = 9:45 p.m., 2 = 10 p.m. and 3 = 10:15 p.m. Stars are plotted to about magnitude 7.5, the asteroid’s brightness at the time. Credit: Chris Marriott’s SkyMap software

I’ve given much thought on how to prepare charts for viewing 2012 DA14. When brightest, it’s not only crossing a great deal of sky in a hurry, but it’s so close to Earth that viewers in say, Vienna, will see it in a somewhat different part of the sky than those in Greece. You can’t make a one-size-fits-all chart for this bugger.

What I did instead was to create two charts – one for Athens, Greece and another for the central U.S. The Greek chart shows the asteroid when closest and brightest; the U.S. chart is centered on Duluth but is useful for a larger region, because the asteroid will be far enough away at that time for the path shift to be much smaller.

Just remember that you’ll need a telescope and good knowledge of the sky to find and follow our friend from the U.S. Use the charts to locate where the asteroid will be at a particular time and then wait for it to arrive as you gaze through the eyepiece.

2012DA14 will have faded to 11.5-12.0 magnitude when it gets dark enough to see it in the U.S., so you’ll need this more detailed chart to find it. Times are Central Standard for Friday Feb. 15, 2013. North is up and stars plotted to mag. 13. Brighter stars labeled with magnitudes. Right-click, save and print out for use at the telescope. Credit: Created with Emil Bonnano’s MegaStar atlas.

I highly recommend two websites that will show you a map of 2012 DA14′s path in your local sky as well as two other options for creating your own map:

Heavens Above - Webmaster Chris Peat has prepared a special 2012 DA14 page on this well-known satellite prediction site. Head over, log in with your location and then click the 2012 DA14 link at the top of the page for a map with times. If you select a spot on the asteroid’s path and click again, you’ll be shown a detailed map with stars to 8th magnitude European, Asian and Down Under sky watchers will find these maps most useful.

* Visual SAT-Flare Tracker 3D - Select your location and click on the 2012 DA14 asteroid header. Then click on the “Best opportunity to see the asteroid from your location” link to see a star map and asteroid path. Be aware that the faintest stars shown here are only about 6th magnitude (naked eye limit), but they’ll still be quite useful for tracking; webmaster Simone Corbellini uses the very accurate JPL Horizons data (see below) for path-making.

* Do-it-yourself – If you have your own star-charting program that allows you to add new asteroids to the database, go to the Minor Planet Center and grab 2012 DA14′s orbital elements. Enter these into your program and print your own star chart. Again, because of how close the asteroid will be, its path might be somewhat different than what your program will show, but at least you’ll be in the neighborhood.

* Tedious but foolproof method – Head over to the JPL Horizon site, type 2012 DA14 into the search box, select your city, time interval (whether you want an asteroid position every 15 minutes, hour or whatever) and then click “Generate ephemeris”. You can hand-plot the positions listed onto a star chart you’ve made with your software program. Be aware that all the times are Universal Time or Greenwich Mean Time (GMT). Subtract 5 hours for Eastern time, 6 for Central and so on. This method has worked very well for me during previous close flybys.

Good luck and I hope a few of you get to see this running rock!

Mid-February bright comet update: Panstarrs, Lemmon, Bressi, Ison

Comet Panstarrs on Feb. 8, 2013 photographed with a 300mm telephoto lens from Castlemaine, Victoria, Australia. Observers describe very bright head and broad tail. Click to see more comet photos. Credit: Michael Mattiazzo.

There are a lot of icy mudballs , ie. comets, flying around up there at the moment, so let’s take a look at what’s happening. We’ll start with C/2011 L4 PANSTARRS, better known as Comet Panstarrs. It’s been slowly brightening to within naked eye range, hovering now right on the edge of visibility under dark skies. Recent observations by amateur comet observers put the comet a smidge above the naked eye limit at magnitude 5.5-5.7. It’s a snap to see in binoculars in morning twilight in the southern hemisphere. As you can tell from the photo, it has an intensely bright, almost star-like head and wide, dusty tail that’s about 1/2 degree long. It should be a most excellent sight in binoculars for both northern and southern hemisphere sky watchers when it emerges at dusk in the western sky next month. We’re only four weeks away!

What a comet! This is Comet Lemmon shot through a 5-inch widefield telescope on Feb. 8, 2013 from Possum Observatory Complex in Gisborne, New Zealand. Click for large version. Credit: John Drummond

Meanwhile, another comet has temporarily stolen the show. C/2012 F6 Lemmon has swelled into a huge, green leek of a thing, Like Panstarrs, it too is faintly visible with the naked eye (mag. 5.8) under dark skies for southern hemisphere skywatchers. How come they get all the fun?

A long, thin exclamation point of a tail shoots from Lemmon’s giant, whipped-up coma or cometary atmosphere. Good news is, the comet is still brightening and may reach 3rd magnitude, making it an easy sight even from the suburbs.

We northerners will have to be patient if we want a glimpse of this comet. Not until early May, when it swings around the sun and enters the morning sky at about magnitude 5, will we get our chance.

You can see the fading of Comet Bressi in this sequence of photos made by Rob Kaufman of Bright, Victoria, Australia.

Then there’s C/2012 T5 Bressi, a modest, unassuming comet that experienced a bright outburst in late January. In a matter of days it became 10 times brighter than expected. On Feb. 4, Bressi glowed at 9.2 magnitude and then slid to 10.5 the very next day.

Sad to say, this is a bad omen for a comet and usually means the beginning of the end. They are crumbly things after all and subject to breakup as their ices volatilize under the relentless sun. Unfortunately, the nail might get hammered into Bressi’s coffin on Feb. 24, when it reaches perihelion or closest distance from the sun (28 million miles). Some comet observers predict it will disintegrate around that time.

Reversed (negaitve) image of Comet ISON on Feb. 3. At the time, the comet was 4 times Earth’s distance from the sun. Credit: Rolando Ligustri / CARA Project

Finally we come to this year’s best hope for a brilliant comet – C/2012 S1 ISON. It’s still slowly cruising through northern Gemini and beautifully placed for telescopic observation every clear night for observers in the northern hemisphere. Would that it were a tad brighter. You still need a 12-inch or larger telescope to see this 15th magnitude fuzzy blotch. I shouldn’t be so offhanded. Ison has developed a short tail of late, lending it enough character to whet our appetite for things to come.

By late fall, ISON should be an easy binocular object in the morning sky. Come Christmas it’s likely to be a glorious sight at dusk. Tag along with me and I’ll let you know how it goes as the clocks ticks cometward.

In darkness the moon is reborn

If we could see the moon today, it would be a very thin crescent only a few degrees from the sun. Tomorrow it’s in new moon phase. Maps created with Stellarium

What’s old today but instantly becomes young again tomorrow? If you guessed the moon, you’re right! Today the moon winds up its current cycle of phases as an exceedingly thin crescent so close to the sun it’s invisible in the solar glare.

The moon’s cycle has always been a metaphor for life. Every month it’s born again as a thin crescent in the western evening sky, grows to a half-pie seven days later and reaches its full power and radiance when full at 14 days. After full, the moon’s radiance declines as its phase wanes to last quarter (21 days) and then to a whiskery crescent at dawn. Before it finally disappears in the sun’s glare, the moon, now 28 days old, reaches the end of its “life” cycle. But only briefly. The very next day, moments after new moon phase, it’s reborn again as an evening crescent.

When we run into troubles in our lives, we might look to the ever-renewing moon for inspiration.

The sky looking west-southwest a half hour after sunset Monday evening Feb. 11, 2013. You might be able to spot dimmer Mars in binoculars.

Tomorrow morning at 2:20 a.m. (CST) the moon will be exactly lined up with the sun and pass through new moon phase. Skywatchers in the western hemisphere won’t see the moon either day because it’s in the same direction as the sun and swamped by glare.

By Monday Feb. 11 however, the moon’s orbital motion will remove it far enough from the sun to be visible during evening twilight.  And there’s a bonus. The crescent will float a few degrees above the planet Mercury.

I’ve removed the atmosphere in this illustration so you can see where the moon is today at noon (CST), tomorrow morning when it reaches new moon phase and tomorrow Feb. 10 at noon. It passes north of the sun, which is in the constellation Capricornus. Notice all the planets in the neighborhood.

If we were to follow the moon today through new moon and into tomorrow, we’d notice it passes well north of the sun. Most of the time, the new moon is either north or south of the sun because its orbit is tipped about 5 degrees relative to Earth’s orbit.

The moon’s tilted orbit causes it to swing north or south (pictured here) of the sun from Earth’s perspective. A couple times a year however it crosses directly in front and a total solar eclipse is visible from somewhere on Earth. Illustration: Bob King

Over the course of its monthly cycle, it bobs up and then down along its tilted orbit. But 2 or 3 times a year, when the moon intersects the plane of Earth’s orbit at the same time as new moon phase, it crosses directly in front of the sun and we see a total solar eclipse. In fact, this is the only time we can see a new moon with the naked eye. It looks exactly like what you’d expect – a blank, black disk scrubbed free of its past life, waiting to begin the next as a tender crescent.

The new moon – black disk – is plainly visible silhouetting the sun during a total solar eclipse. Credit: Luc Viatour

Space station and (maybe) auroras return to evening sky

A gorgeous northern lights fills the sky over Faskrudsfjordur, Iceland earlier today Feb. 8, 2013. This image was taken by photographer Jónína Óskarsdóttir. Click the photo to see her eye-watering aurora photo gallery.

Alaskans, Norwegians and Icelanders have something in common this week beside the cold. They’ve all been watching displays of the northern lights which have bloomed over Arctic latitudes night after night since late January. I know they’d be happy to share the sight with us in the lower 48, and maybe they’ll have the chance.

Auroras might reach down into the northern U.S. sometime tonight through Sunday. There is a 35% chance for a major storm in far northern latitudes and a 10% chance for minor storming in the mid-north latitudes where much of the world lives. I interpret that to mean a glowing arc pierced by a few rays low in the northern sky.

While not exactly a big blast, it’s worth keeping an eye out for that greeny glow . Since the sun’s been very quiet lately, a solar flare is not behind the uptick in activity. Rather an enhancement in the solar wind is behind the current forecast.

Photo taken Feb. 1, 2013 from Quyta Lake, Northwest Territories, Canada. Looks like it was ideal time for snow-angel-making under the aurora borealis. Credit and copyright: Yuichi Takasaka – www.blue-moon.ca

Joining the night scene will be the International Space Station. It returns to the evening sky for much of the U.S. and Canada starting tomorrow and continuing the next few weeks. Take note of the fine Valentine’s Day pass. The times below are for the Duluth, Minn. region. For times and directions to look for your town, type your zip code into Spaceweather’s Satellite Flybys page or log in to Heavens Above. You can also get free e-mail alerts via NASA’s Spot the Station.

* Sat. Feb. 9 starting at 7:20 p.m. Brief pass low in the southwestern sky
* Sun. Feb. 10 at  6:30 p.m. Travels across the southern sky below Orion
* Mon. Feb. 11 at 7:15 p.m. Brilliant pass up from the west into the southern sky. Disappears into Earth’s shadow below the planet Jupiter at 7:18 p.m.
* Tues. Feb. 12 at 6:24 p.m. Cuts across bottom of Orion’s Belt about 6:28 p.m.
* Weds. Feb. 13 at 7:10 p.m.  Brilliant pass! Just when the ISS is nearly overhead, it fades away as it enters Earth’s shadow about 7:13 p.m.
* Thurs. Valentine’s Day at 6:19 p.m. Bright pass high in the southern sky. Slides under the planet Jupiter about 6:22 p.m. Time it right, and you can give your sweetheart this celestial surprise gift during your night out on the town.