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Update 2: JPL Small Body Database has been updated with radar data for 2010 AL30.

Update 1: Bernhard Haeusler (B82 Maidbronn, Germany) posted an animation of the NEO asteroid 2010 AL30, 100 x 2s. exposure, taken on January 13 between 01:01 and  01:16 GMT (~13MB).

Today, at 12:46 GMT, the asteroid with temporary designations 2010 AL30, discovered on January 10 by the Lincoln Near-Earth Asteroid Research (LINEAR) survey, flew by our planet at the distance of 0.000 86 AU (129,060 km; about 33% of the distance to the Moon). Within the next few hours, its brightness and elongation will drop dramatically and the object will disappear until the next (relatively) close approach in August 2028 (0.079 35 AU ~ 11.87 mil. km).

Thanks to photometric observations from around the world, pointing uncertainties have shrunk from about 523 arcseconds (3-sigma) to about 7 arcseconds. The new orbit calculations were accurate enough to point the radio telescopes of the Goldstone Observatory in Mojave Dessert at the asteroid. Early in the morning, between 02:20 and 04:20 GMT, astronomers were able to obtain valuable radar data which will dramatically improve the object’s orbit and provide additional information on its size and shape.

Lance Benner of NASA/JPL reported strong radar echoes from 2010 AL30 at Goldstone. The bandwidth was consistent with the asteroid’s expected size (10-20m). Bill Ryan and Richard Miles determined the rotation period to be roughly 9 minutes.

2010 AL30 imaged by a SLOOH telescope on January 13 at 03:02 GMT - Credit: Tavi Greiner / SLOOH

The image above displays 2010 AL30 taken by the SLOOH robotic observatory on the Canary Islands. The SLOOH space camera takes gray-scale image. To make a color image, the camera takes exposures with different filters. The individual filtered images are later combined into a single color image (just as the red, green and blue channels are combined to form a color picture). Because the asteroid was relatively close, long exposure left trails as the object moved relatively to background stars. Since different color filters were used at different times, in this case red was used first, then green and finally blue, the individual color trails do not overlap in the final image and reveal the tricolored line.

Series of 30 15" exposures tracking on 2010 AL30 between 07:18:16 and 07:27:29 GMT - Credit: Patrick Wiggins

The two captures above are compositions of series of exposures Patrick Wiggins took with a C-14 @ f/5.5 telescope and SBIG ST-10 binned 3×3 using clear filter. The Field of View (FOV) is about 18′ x 26′.  Note that in the second one the target is pretty faint (not surprising for 1″ exposures) so you have to look close to see it as it moves from left to right.

2010 AL30 imaged on January 12 from the distance of 0.003 7 AU at the Nazaret Observatory at the Canary Islands - Credit: Gustavo, Muler, Schteinman - Observatorio Nazaret, J47

Click on the image above to see the apparent motion of 2010 AL30. Also, here is a composition of  200 images (~ 10MB).

Trajectory of Asteroid 2010 AL30 Past Earth on January 12/13, 2010 - Credit: NASA/JPL Near-Earth Object Program Office (Don Yeomans, Paul Chodas, Steve Chesley & Jon Giorgini)

Because of the unusual orbital period of 2010 AL30, which is almost precisely 1 year (366 days) some have suggested it could have been a man-made rocket stage in orbit about the Sun. Nevertheless, trajectory extrapolations show that the object cannot be associated with any recent launch and it has not made any close approaches to the Earth since well before the Space Age began (the last relatively close approach occurred at 08:09 GMT on August 17, 1947 when 2010 AL30 passed the Earth at the distance of 0.038 97 AU ~ 5.8 mil. km). Therefore, NASA’s Jet Propulsion Laboratory (JPL) Small Body Database has officially classified 2010 AL30 as a Near-Earth Object (NEO) of type Apollo (Near-Earth asteroids which cross the Earth’s orbit, similar to that of 1862 Apollo, i.e. with semi-major axis, a > 1.0 AU and perihelion distance, q < 1.017 AU).

In the end,  the story of 2010 AL30 had a happy ending for inhabitants of the planet Earth; we’ve dodged yet another bullet. Even if 2010 AL30 had been on a collision course with our planet, it posed only a minimal risk as it would have certainly break up in Earth’s atmosphere. According to NASA/JPL one could expect a near-Earth asteroid of this size to pass within the moon’s distance about once every week on average.

For more 2010 AL30 images, fly-by animation and the apparent orbit sky chart see my earlier post.

Update 6: See the latest 2010 AL30 post for new information and most recent photos.

Update 5: As more observations of 2010 AL30 were submitted to the Minor Planet Center (MPC), the greatest uncertainty (3-sigma/”) for the January 13 fly-by has been reduced from about 500″ to a mere 7″ (MPEC 2010-A65 – 2300 GMT).

Update 4: NASA’s Jet Propulsion Laboratory (JPL) Small Body Database now officially classifies 2010 AL30 as a NEO asteroid of type Apollo (Near-Earth asteroids which cross the Earth’s orbit, similar to that of 1862 Apollo, i.e. with semi-major axis, a > 1.0 AU and perihelion distance, q < 1.017 AU).

Update 3: Below is an image of asteroid 2010 AL30 taken by Dave Herald on January 12 at 15h 46m GMT. The asteroid is the dot near the center of the image. Image is a stack of 5 x 4-sec exposures using a 35cm SCT. The CCD was binned to give a 2″ pixel size to give greater sensitivity, and to be consistent with asteroid motion – which was 0.56″/sec at the image time.

Image of asteroid 2010 AL30 taken on Jan 12 at 15h 46m GMT with a 35cm Schmidt Cassegrain Telescope - Credit: Dave Herald

Update 2: Thanks to recent observations around the world, the Minor Planet Center (MPC) has improved the orbital uncertainty of 2010 AL30 to 5, which is equivalent to an in-orbit longitude runoff of less than 1692 arcsec / decade (MPEC 2010-A61 – 1251 GMT).

Update 1: Ernesto Guido & Giovanni Sostero we able to follow 2010 AL30 using a Global-rent-a-scope (GRAS) network telescopes in Mayhill, New Mexico, to produce the following composition of 16 10-second long exposures.

2010 AL30 follow-up on Jan 12.37 through the Global Rent-a-Scope (GRAS) Network using a scope located in Mayhill (NM) - Credit: Ernesto Guido & Giovanni Sostero

Asteroid 2010 AL30 was discovered on January 10 by a 1.0-m f/2.15 reflector + CCD at the Lincoln Laboratory ETS (observers M. Blythe, G. Spitz, R. Brungard, J. Paige, P. Festler), in New Mexico, as a part of the Lincoln Near-Earth Asteroid Research (LINEAR) survey . The discovery was published in the Minor Planet Electronic Circulars (MPEC) MPEC 2010-A59 issued at 15:43 GMT on January 11.

Strangely enough, preliminary orbit calculations point to orbital period equal almost exactly 1 year (366 days) and its close encounters with Venus could suggest an artificial origin (rocket booster or some other space junk from a spacecraft sent on a mission to Venus in 1985, 2003, or 2006). Nevertheless, since the orbit does not resemble any useful trajectory and the object’s encounter velocity with the Earth is not unusually low (9.5 km/sec), the period is most likely a coincidence and 2010 AL30 is a typical NEO with an ordinary Earth-crossing orbit (with MOID = 0.000 037 963 AU = 5 680 km)

Since the object is almost on an impact trajectory, this is a great example of how much warning time we have for an object with H = 27.0 (about 10-20m). 2010 AL30 also approaches the Earth from the night side, from almost exactly opposite direction than the Sun (just 15 degrees off of the exact anti-solar direction). Were coming from the other side of the sky (solar direction), we would not see it until hours after the closest approach.

During the close approach, the asteroid will be best observed a few hours before passing the perigee (January 13, 12:47 GMT) from Hawaii, New Zealand and the east coast of Australia, traveling through the constellations of Canis Minor, Orion, and Taurus. Shortly after the closest approach, the object’s brightness will drop dramatically and with elongation below 20 degrees, 2010 Al30 will disappear in the sunlight. Below is a sky chart with the (approximate) apparent position of 2010 AL30 between January 12 and January 14.

The apparent orbit of the asteroid during 2010 AL30, 12 January 00:00 GMT to 14 January 06:00 GMT - Credit: Gerhard Dangl

Update 3: See the latest 2010 AL30 post for new information and most recent photos.

Update 2: See my new post for more photos and fly-by animation.

Update 1: See the my most recent 2010 AL30 post for updates and a fly-by animation.

On Wednesday, January 13, 2010 at 12:48 GMT, a newly discovered asteroid with temporary designation 2010 AL30 will fly by the Earth at the distance of 0.000 86 AU (129,060 km; about 33% of the distance to the Moon). The asteroid has a diameter of approximately 10-25 meters and poses no risk to anyone, as not only is the calculated perigee distance quite accurate, but in a case of the encounter with Earth’s atmosphere, it would certainly break up and rain down only a few small fragments (meteorites).

At around 10 UT on January 13, the object could reach a maximum brightness of 13.8 magnitude and despite a large relative motion (about 10 arcsec/second) should be easily observable with a medium size equipment.

Orbit Diagram of 2010 AL 30 - Source: NASA JPL

2010 AL30 will also have closer encounters with our Moon (January 14, 2010 at 0.001 86 AU), Mars (July 24, 2039 at 0.089 6 AU) and several close encounters with Venus (May 16, 2012, August 2, 2016, January 5, 2037, etc.)

Update 4: Below is a spectacular shot of the meteor captured by Robert Mikaelyan

Fireball Meteor Over Groningen captured around 17:00UTC on Tuesday Netherlands - Source: Robert Mikaelyan

Update 3: Koen Miskotte estimated the meteor’s brightness between -8 and -12.  According to his report the red orange fireball broke up in 5/6 pieces each one with a magnitude of -3 to -5. There are also reports of a sonic boom and a rumbling sound and shaking windows.

Update 2: Pictures of the smoke trail left by the bolide at dusk have appeared in a forum.

Update 1: According to the EXIF data of the original meteor photo, it was taken at 16:58:24 UTC between Assen and Groningen.

People in the Netherlands and Germany are reporting an extremely bright fireball seen around 19.00 CEST (17:00 UTC), traveling more or less south-north. Daniel Fisher of the Nuremberg Astronomical Association posted a photo of the meteor Daniel Fischer twittered links to a report posted on a mailing-list run by the Nuremberg Astronomical Association as well as to a a photo of the meteor:

A bright fireball seen over the Netherlands and Germany on October 13, 2009 at 16:58:24 UTC - Source: Jan de Vries

Theo Jurriens from the Kapteyn Astronomical Institute of University of Groningen, and KNMI – the Royal Netherlands Meteorological Institute, confirmed about one hundred reports received from the public. The meteor has been seen to burst into three pieces eventually.

Bolide smoke trail over the Dutch sky

Last night, fans at the Beach Bums game in Traverse City in Michigan reported seeing a bright meteor in the night sky.

“We were watching the game and then all of a sudden something caught our eyes.”
“We looked up really quick and there was this big, bright fireball… it seemed like it was right on top of us like you almost had to duck it seemed so low.”

There are also reports of a loud explosion, thus the object must have reached low enough altitudes where the air thickens enough that sound can propagate through it.

We thought someone set off dynamite – the boom shook the house.

This sighting adds to the series of bright meteors seen around the world recently. The number of similar reports in the last year should really be attributed to the rise of social media rather than increasing number of meteor activity. About 3,000 meteors are set ablaze in our atmosphere every day.

The space around us is filled with interplanetary debris. As of August 30, 2009, 6292 Near-Earth Objects (NEO) have been discovered. 1062 of these NEOs are asteroids with a diameter of approximately 1 kilometer or larger. Also, 145 of these NEOs have been classified as Potentially Hazardous Asteroids (PHAs).

Only yesterday, at 11:46:36 UTC the asteroid labeled as 2009 QC35, discovered by the Catalina Sky Survey on August 29, passed the Earth at a distance of about 0.0075 AU which roughly represents 2.9 Lunar Distances (LD). The separation of 1,113,500 km is considered quite close by space standards.

Orbit Diagram of 2009 QC35 - Source: NASA JPL

2009 QC35 has an estimated diameter of 23-52m. It is not one of the largest among Apollo asteroids (Earth-crossing NEOs with semi-major axis greater than 1.0 AU and perihelion distance less than 1.017 AU), nevertheless a collision with our planet would cause a great damage and leave a long lasting scar.

The Barringer Meteor Crater in Arizona created approximately 49,000 years ago by a nickel-iron meteorite with the diameter of about 50 meters

Today at 23:58 UT asteroid labeled as 2009 FP will pass the Earth at a distance of about 0.003 AU which roughly represents 1.2 Lunar Distances (LD). The comfortable separation of 445,000 km is not a “hair” per se, nevertheless it is quite close by space standards.

Orbit Diagram of 2009 FP - Source: NASA JPL

This Near Earth Object (NEO) was discovered at 05:46 UT on March 29 by Mount Lemmon Survey (MLS) in Arizona, one of the three facilities of the Catalina Sky Survey. The probability of impacting the Earth is only 1 in 133,000. The asteroid has a diameter of approximately 10 meters and poses no risk to anyone as it would certainly break up in the Earth’s atmosphere and rain down only a few small fragments (meteorites).

Astronomers have been conducting surveys to locate objects whose orbits bring them to close proximity with the Earth for decades. However, automatization techniques first introduced by LINEAR program greatly increased the numbers of discovered asteroid in the last ten year. LINEAR alone is responsible for the discovery of more than 220,000 new objects out of which more than 2,000 classify and NEO’s (NEO is a Solar System object with perihelion distance less than 1.3 AU).

NEO Chart - Source: NASA JPL

It might seem that Earth’s neighborhood got filled fill space junk suddenly as news of fireballs have filled internet blogs and even TV news over the past 6 months. Fortunately, it is far more likely that general public and media simply pay more attention to these events. Additionally, astronomers are becoming better at detecting even the smallest objects days before they pass the Perigee of their orbits. Bad Astronomer offers a great explanation for this “puzzling” phenomenon:

I think it’s a mix of coincidence — there may be a few more than usual, but it’s not like these things have published schedules; sometimes there are more and sometimes fewer — together with people being more aware of them because they’ve been in the news lately. It’s like buying a car and suddenly seeing it everywhere when you drive. We notice what we’re primed to notice.

Below is a short list of notable objects that crossed path with Earth in the past six month:

On October 6, 2008 Richard A. Kowalski of the Catalina Sky Survey discovered a meteoroid, later labeled as  2008 TC3, that entered Earth’s atmosphere only 20 hours later, at 02:46 UT on October 7, 2008 over Sudan. There was great excitement in NEO community as it was the first time a prediction was issued about an object entering Earth’s atmosphere. Consequent observations led to discovery of several fragments of the original piece of rock that measured about 5 meters in diameter. Here is an animation of what an observer on the asteroid would see in the last hours before the atmospheric entry.

A very bright fireball lit up the skies in Alberta and Saskatchewan, Canada around 22:30 UT on Thursday, November 20, 2008.

Only two months later this footage from Sweden captures a spectacular meteor that entered Earth’s atmosphere on January 17, 2009.

It is quite rare to see a meteor during daylight as most meteors are too faint to be noticed. One of the exceptions is the great fireball of 1972 which was the first Earth-grazing object ever observed.

Earth-grazing fireballs are caused by a meteoroid that enters the atmosphere but overcomes the Earth’s gravity and exists back into outer space. Only four grazers have been scientifically observed.

A very bright daylight meteor was seen over Texas on February 15, 2009. Only a few days later, two astronomers claimed to have found meteorite debris.

On March 2, 2008 at 13:45UT we had the first close miss of March when Asteroid 2009 DD45, discovered only a few days before, reached the perigee distance of 72,000 km.

Orbit Diagram of 2009 DD45 - Source: NASA JPL

Two weeks later, on March 18 at 12:17 UT another interplanetary rock 15 meters across, 2009 FH, flew by reaching minimal geocentric distance of 79,000 km. Both of these objects passed us at only twice the altitude of geostationary satellites.

Orbit Diagram of 2009 FH - Source: NASA JPL

If this feels like the Universe is out there to get us … well … that’s right. We know with 100% certainty that it will eventually succeed.