2008 TC3 – Sudanese Fireball Meteorite Recovered

Last year on October 6, a tiny asteroid was discovered in space. Unlike all of the asteroids discovered before this one, this asteroid (named 2008 TC3) was on a collision course with Earth. Only 20 hours after discovery, the 2-meter in diameter asteroid entered the Earth’s atmosphere over northern Sudan in Africa.

The New Scientist magazine reports that researchers from the University of Khartoum (in Sudan) and NASA have found meteorites from the impact of 2008 TC3. This marks not only the first time that an object was observed in space before impacting the Earth or its atmosphere, but also the first time an object was studied in space as an asteroid and on the ground as a meteorite.

The New Scientist report can be found here.

A PDF presentation by Lindley Johnson, head of NASA’s Near-Earth Object Observation program, can be found here. This presentation also includes photos of one of the meteorite. It is also a nice summary of the current state of the surveys which search for Near-Earth asteroids and comets.

Past Transient Sky posts include:

“Incoming Fireball Over Sudan!!! – 2008 TC3“, “More on the Sudanese Fireball – 2008 TC3“, “Report on the Impact of 2008 TC3“

Meteorites Fround From Last Friday’s Texan Daylight Fireball

For an earlier post on this fireball/meteorite see: “Feb 15 Texas Daylight Fireball“

Thanks to eyewitness reports, a few great videos and some amazing weather radar images, two groups of meteorite researchers and collectors have been able to find multiple meteorites from last Friday’s daylight fireball over Texas. So far the meteorites have been found in an area near the small towns of West and Denton, Texas about 50 miles south of Dallas/Fort Worth.

Thanks to Eman for posting this update to the comment section.

“I want to confirm that several meteorites have now been recovered from this event in the vicinity of Denton, TX and the Central Texas Town of “West. TX”. Initial estimates are a strewn field a mile wide and 6-7 miles long. No major masses have been reported thus far. 20-40 stones so far, most are egg and thumbnail sized.”

The meteorites have been found by two groups. One group is being led by Ron DiIulio, director of the planetarium and astronomy lab program at the University of North Texas, and Preston Starr, the observatory manager at UNT. Local news stories describing their finds can be seen here and here.

Some of the meteorites found by the UNT team will be on display at the UNT Elm Fork Education Center on March 7. This exhibit is part of their Family Fun Science Event. There is an admission charge of $8 per child though two adults are allowed to enter for free with each child. More on this event can be found here.

The second group of meteorite finders is led by Michael Farmer, a Tucson-based meteorite collector and dealer. There is a nice video of Michael and his team discussing the hunt for this and other meteorites. According to Michael there are many other groups scouring the ground for meteorites and that number will probably only increase.

The large number of meteorites being found does not mean multiple meteoroids or small asteroids produced the fireball. The meteorites are caused by a single asteroid which broke into many pieces as it experienced the intense pressure and heat of passage through the Earth’s atmosphere at many miles per second. It is very possible that there are hundreds to thousands of small meteorites spread over an area on the order of ~100 square miles. Meteorites are named after the closest geographic feature to where they are found. It will be interesting to see what this meteorite will be called.

Meteorites from Canadian Fireball Have Been Found!

Scientists from the University of Calgary have successfully found a number of meteorites from the spectacular fireball seen over western Canada on November 20th. The meteorites were found strewn over a many kilometer-wide area near the city of Lloydminster along the borders of Alberta and Saskatchewan. This spot is very close to the predicted fall area based on eyewitness reports and videos of the fireball.

A good story on the meteorite finds can be found at the Washington Post.

A more detailed and personal account of the meteorite hunt and finds was posted by Bruce McCurdy on the Meteorobs e-mail group.

Though the analysis is still preliminary, and might even be considered hearsay at this point, the meteorites appear to be a type of Ordinary Chondrite (OC). OCs are the most common type of meteorites seen to fall to Earth and are related to S-type asteroids. Though S-type asteroids are not the most common type of asteroid in space they are the dominant type in the inner half of the asteroid Main Belt between Mars and Jupiter. It is from this region of the asteroid Main Belt that the majority of the asteroids and meteoroids that cross the Earth’s orbit (and hence can impact the Earth) come from.

When the small asteroid that caused the fireball was traveling through space it was a single chunk of rock. Early estimates put its size and mass at up to a few meters across and up to 10 tons. During its quick trip through the Earth’s atmosphere, atmospheric and thermal (heat) forces broke the asteroid up into hundreds or thousands of pieces. Though much of its mass completely burnt up, enough of the remaining pieces survived to hit the ground to be found as meteorites.It is possible that there are thousands of meteorites to be found from this fireball.

Over the next few weeks or months analysis of the fireball’s orbit and the composition of the meteorites will be published. I will post further updates as more info is released.