2008 TC3(Catalina Sky Surveytemporary designation8TA9D69) was an 80-tonne (80-long-ton; 90-short-ton), 4.1-meter (13 ft) diameterasteroid[2]that enteredEarth's atmosphereon October 7, 2008.[3]It exploded at an estimated 37 kilometers (23 mi) above theNubian DesertinSudan.Some 600meteorites,weighing a total of 10.5 kilograms (23.1 lb), were recovered; many of these belonged to a rare type known asureilites,which contain, among other minerals,nanodiamonds.[2][4][5]
 | |
| Discovery | |
|---|---|
| Discovered by | Catalina Sky Survey |
| Discovery date | October 6, 2008, 06:39 UTC |
| Designations | |
| 2008 TC3 | |
| Orbital characteristics[1] | |
| EpochOctober 7, 2008 (JD2454746.5) | |
| Uncertainty parameter4 | |
| Observation arc | 1 day (575 observations) |
| Aphelion | 1.71644AU(256.776Gm) |
| Perihelion | 0.899957 AU (134.6317 Gm) |
| 1.308201 AU (195.7041 Gm) | |
| Eccentricity | 0.312065 |
| 1.50yr(546.53d) | |
| 330.7541° | |
| 0.6587071°/day | |
| Inclination | 2.54220° |
| 194.101138° | |
| 2008-Nov-20 | |
| 234.44897° | |
| JupiterMOID | 3.57975 AU (535.523 Gm) |
| Physical characteristics | |
| Dimensions | 4.1 meters |
| Mass | 80tonnes(80,000kg) |
Meandensity | ~1.5 g/cm3 |
| 0.0269409h(1.61645min)[1] | |
| 0.1±0.03 | |
| F/M | |
| 30.4[1] | |
It was the first time that anasteroid impact had been predictedbefore its entry into the atmosphere as ameteor.[6]
Discovery
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The asteroid was discovered byRichard A. Kowalskiat theCatalina Sky Survey(CSS) 1.5-meter telescope atMount Lemmon,north ofTucson, Arizona,US, on October 6, 06:39 UTC, 19 hours before the impact.[7][8][9]
It was notable as the first such body to be observed and tracked prior to reaching Earth.[6]The process of detecting and tracking anear-Earth object,an effort sometimes referred to asSpaceguard,was put to the test. In total, 586 astrometric and almost as many photometric observations were performed by 27 amateur and professional observers in less than 19 hours and reported to theMinor Planet Center,which in eleven hours issued 25 Minor Planet Electronic Circulars with new orbit solutions as observations poured in. On October 7, 01:49 UTC,[9]the asteroid entered the shadow of the Earth, which made further observations impossible.
Impact predictions were performed byUniversity of Pisa's CLOMON 2 semi-automatic monitoring system[10][11]as well asJet Propulsion Laboratory'sSentrysystem. Spectral observations that were performed by astronomers at the 4.2-meterWilliam Herschel TelescopeatLa Palma,Canary Islandsare consistent with either aC-typeorM-type asteroid.
Entry
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2008 TC3·Sun·Earth
Themeteorentered Earth's atmosphere above northernSudanat 02:46 UTC (05:46 local time) on October 7, 2008, with a velocity of 12.8 kilometers per second (29,000 mph) at anazimuthof 281 degrees and an altitude angle of 19 degrees to the local horizon. It exploded tens of kilometers above the ground with the energy of 0.9 to 2.1kilotons of TNTover a remote area of theNubian Desert,causing a large fireball orbolide.[12]
The Timesreported that the meteor's "light was so intense that it lit up the sky like a full moon, and an airliner 1,400 km (870 mi) away reported seeing the bright flash."[13]A webcam captured the flash lighting upEl-Gounabeach 725 kilometres north of the explosion (seethis webcam frame).[14]A low-resolution image of the explosion was captured by the weather satelliteMeteosat 8.[15]The Meteosat images place the fireball at21°00′N32°09′E/ 21.00°N 32.15°E.[16]Infrasounddetector arrays inKenyaalso detected a sound wave from the direction of the expected impact corresponding to energy of 1.1 to 2.1 kilotons of TNT.[17]Asteroids of this size hit Earth about two or three times a year.[18]
The trajectory showed intersection with Earth's surface at roughly20°18′N33°30′E/ 20.3°N 33.5°E[19]though the object was expected to break up perhaps 100–200 kilometers (60–120 mi) west as it descended, somewhat east of theNile River,and about 100 kilometers (60 mi) south of theEgypt–Sudan border.
According to U.S. government sources[20][21]U.S. satellites detected the impact at 02:45:40 UT, with the initial detection at20°54′N31°24′E/ 20.9°N 31.4°Eat 65.4 kilometers (40.6mi;35.3nmi) altitude and final explosion at20°48′N32°12′E/ 20.8°N 32.2°Eat 37 kilometers (23 mi; 20 nmi) altitude. These images have not been publicly released.
Recovered fragments
editThis section needs to beupdated.The reason given is: In 2022, Bischoff et al. concluded that the meteorite's classification as a ureilite may not be correct.[1]Their findings and the impact they may have on the 2009 Jenniskens study need to be incorporated.(November 2023) |
A search of the impact zone that began on December 6, 2008, turned up 10.5 kilograms (23 lb) of rock in some 600 fragments. Thesemeteoritesare collectively namedAlmahata Sitta[22](Arabic:المحطة ستة), which means "Station Six"[23]and is a train station betweenWadi HalfaandKhartoum,Sudan. This search was led byPeter Jenniskensfrom theSETI Institute,Californiaand Muawia Shaddad of theUniversity of KhartouminSudanand carried out with the collaboration of students and staff of the University of Khartoum. The initial 15 meteorites were found in the first three days of the search. Numerous witnesses were interviewed, and the hunt was guided with a search grid and specific target area produced byNASA'sJet Propulsion LaboratoryinPasadena, California.[24][25][26][27][28]
Samples of the Almahata Sitta meteorite were sent for analysis to a consortium of researchers led by Jenniskens, the Almahata Sitta consortium, includingNASA AmesinCalifornia,theJohnson Space CenterinHouston,theCarnegie Institution of Washington,andFordham UniversityinNew York City.The first sample measured was an anomalous ultra-fine-grained porouspolymictureiliteachondrite,with largecarbonaceous grains.Reflectance spectra of the meteorite, combined with the astronomical observations, identified 2008 TC3as anF-type asteroid.Fragile anomalous dark carbon-richureiliteslike in the Almahata Sitta meteorite are now firmly linked to the group of F-class asteroids.[2][clarification needed]Amino acidshave been found on the meteorite.[29]The nanodiamonds found in the meteorite were shown to have grown slowly, implying that the source is another planet in the solar system.[30]More recently, in December 2020, further studies on the fragments have been reported. These studies revealed an extremely rare form of hydrated crystals, in a fragment called AhS 202, known asamphibole,suggesting to the researchers that 2008 TC3 early on likely belonged to a very large Ceres-classdwarf planet.[31]
Richard Kowalski,who discovered the object, received a tiny fragment of Almahatta Sitta, a gift from friends and well-wishers on the Minor Planet Mailing List, which Kowalski founded in order to help connect professional and amateur astronomers.[32]
Gallery
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Meteosat 8/EUMETSAT visual image of first light flare from 2008 TC3with lat/long reference -
Meteosat 8/EUMETSAT IR image of main fireball from 2008 TC3 -
Meteosat images combined, showing offset from first light flare to main IR flare
See also
editReferences
edit- ^abc"JPL Small-Body Database Browser: (2008 TC3)"(last observation: October 7, 2008;arc:1 day). Jet Propulsion Laboratory.RetrievedMarch 28,2016.
- ^abc Jenniskens, P.; et al. (2009). "The impact and recovery of asteroid 2008 TC3".Nature.458(7237): 485–488.Bibcode:2009Natur.458..485J.doi:10.1038/nature07920.PMID19325630.S2CID7976525.
- ^ Plait, P. (October 6, 2008)."Incoming!!!".Bad Astronomy.Archivedfrom the original on October 7, 2008.RetrievedOctober 8,2008.
- ^ Chang, K. (March 25, 2009)."Recovered Pieces of Asteroid Hold Clues to Early History".The New York Times.Archivedfrom the original on November 13, 2013.RetrievedMarch 26,2009.
- ^Borenstein, S. (March 26, 2009)."Astronomers catch a shooting star for 1st time".ABC news.The Associated Press.Archived fromthe originalon March 29, 2009.RetrievedSeptember 15,2009.
- ^ab Roylance, F. (October 7, 2008)."Predicted meteor may have been sighted".Maryland Weather.Archivedfrom the original on October 10, 2008.RetrievedOctober 8,2008.
- ^ Williams, G. V. (October 6, 2008)."MPEC 2008-T50".Minor Planet Center.Archivedfrom the original on October 9, 2008.RetrievedOctober 8,2008.
- ^ Huntington, J. (October 7, 2008)."Small Asteroid Enters Earth's Atmosphere".eFluxMedia. Archived fromthe originalon October 10, 2008.RetrievedOctober 8,2008.
- ^ab Chesley, S.; Chodas, P.; Yeomans, D. (November 4, 2008)."Asteroid 2008 TC3 Strikes Earth: Predictions and Observations Agree".Near Earth Object Program.NASA.Archived fromthe originalon June 18, 2009.RetrievedJune 18,2009.
- ^ "NEODys Main Risk Page".RetrievedOctober 8,2008.
- ^ "NEODys2008 TC3page ".RetrievedOctober 8,2008.
- ^ "Astronomers predict shooting star over Sudan from space boulder".Agence France-Presse.October 6, 2008. Archived fromthe originalon October 11, 2008.RetrievedOctober 8,2008.
- ^ Simon, P. (October 8, 2008)."Weather Eye: NASA spots asteroid before annihilation".The Times.RetrievedOctober 8,2008.[dead link]
- ^
Javaux, G."2008 TC3... Première détection d'un astéroïde avant son impact sur Terre... quelques heures plus tard"(in French).RetrievedSeptember 15,2009.
Une webcam de surveillance, située sur la plage de la Mer Rouge à El Gouna en Egypte, a enregistré indirectement le flash de l'explosion qui s'est produit à environ 725 km plus au sud.
- ^ "Asteroid Impact".SpaceWeather.com. October 8, 2008.Archivedfrom the original on October 10, 2008.RetrievedOctober 8,2008.
- ^ "m8 HRV 200810070245".October 8, 2008. Archived fromthe originalon October 17, 2008.RetrievedOctober 8,2008.
- ^ "Impact of Asteroid 2008 TC3 Confirmed".Near Earth Object Program.October 7, 2008. Archived fromthe originalon October 10, 2008.RetrievedOctober 8,2008.
- ^ Borenstein, S. (October 6, 2008)."Small Asteroid Headed for Light Show Over Africa".ABC News.The Associated Press.RetrievedSeptember 15,2009.[dead link]
- ^ Mike (October 6, 2008)."Very near NEO Meteoroid impact!".MKVH.de. Archived fromthe originalon October 10, 2008.
- ^ "Asteroid Update".SpaceWeather.com. October 15, 2008.RetrievedOctober 18,2008.
- ^ "Fireball detection".University of Western Ontario.October 15, 2008.RetrievedOctober 18,2008.
- ^ "Almahata Sitta".Meteoritical Bulletin Database.August 12, 2013.RetrievedAugust 13,2013.
- ^Gebauer, S. (April 16, 2008)."Station Nr. 6. – Nubian Desert".Panoramio.Archived fromthe originalon December 30, 2008.RetrievedJune 15,2009.
- ^ "NASA Team Finds Riches in Meteorite Treasure Hunt".NASA.March 27, 2009.Archivedfrom the original on March 31, 2009.RetrievedApril 5,2009.
- ^ "Found: Pieces of meteorite spotted before impact".New Scientist(2697): 15. February 25, 2009.
- ^ Shiga, D. (February 19, 2009)."First tracked space rock recovered after impact".New Scientist.
- ^ Courtland, R. (March 25, 2009)."Meteorite hunters 'strike gold' in Sudan".New Scientist.Archivedfrom the original on April 29, 2009.RetrievedApril 4,2009.
- ^ Kwok, R. (March 26, 2009)."Astronomy: The Rock That Fell to Earth".Nature.458(7237): 401–403.doi:10.1038/458401a.PMID19325604.
- ^ "Life's Building Blocks Found on Surprising Meteorite".Space.com.December 16, 2010.RetrievedAugust 13,2013.
- ^Nabiei, Farhang; et al. (April 17, 2018)."A large planetary body inferred from diamond inclusions in a ureilite meteorite".Nature Communications.9(1). Springer Nature: 1327.Bibcode:2018NatCo...9.1327N.doi:10.1038/s41467-018-03808-6.ISSN2041-1723.PMC5904174.PMID29666368.
- ^Dockrill, Peter (December 22, 2020)."Meteorite Clues Point to a Huge, Unknown Object in The Early Solar System".SpaceAlert.com.RetrievedDecember 22,2020.
- ^Lakdawalla, E. (September 20, 2009)."A piece of an asteroid returns to the telescope that discovered it".The Planetary Society.Archived fromthe originalon March 4, 2012.RetrievedOctober 7,2009.
Further reading
edit- Atkinson, N. (October 13, 2008)."Where Are the Images from Asteroid 2008 TC3?".Universe Today.Archivedfrom the original on February 15, 2009.RetrievedJune 8,2009.
- "80-ton asteroid's impact recorded".BBC News.March 25, 2009.RetrievedAugust 13,2013.
- Dockweiler, T. (March 12, 2009)."Earth's First Pre-Known Asteroid Impact: The Sudan Event of October 7, 2008"(PDF).Science Newsletter.4(3). Triton Fun Company: 1–2. Archived fromthe original(PDF)on February 22, 2012.RetrievedAugust 13,2013.
- Gayon-Markt, J.; Delbo, M.; Morbidelli, A.; Marchi, S. (April 30, 2012)."On the origin of the Almahata-Sitta meteorite and 2008 TC3asteroid ".Monthly Notices of the Royal Astronomical Society.424(1): 508–518.arXiv:1206.3042.Bibcode:2012MNRAS.424..508G.doi:10.1111/j.1365-2966.2012.21220.x.S2CID119242802.
- Lakdawalla, E. (October 7, 2008)."The full story of Earth-impacting asteroid 2008 TC3".The Planetary Society.RetrievedAugust 13,2013.
- Yeomans, D. (October 7, 2008)."Small Asteroid Predicted to Cause Brilliant Fireball over Northern Sudan".Near Earth Object Program.Archived fromthe originalon April 6, 2013.RetrievedAugust 13,2013.
External links
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| External images | |
|---|---|
 An image of2008 TC3 | |
| Animation of2008 TC3 | |
| Smoky trail (spaceweather.com November 8, 2008) |
- Remanzacco Observatory photographs of the incoming space rock
- Telescopio Nazionale Galileo photograph of 2008 TC3
- Announcement with animation
- "webcam record of flash effect from Red Sea beach at El Gouna, Egypt, 725 km away"(GIF).Archivedfrom the original on March 14, 2011.RetrievedJune 8,2009.
- NASA Astronomy Picture of the Day: Almahata Sitta 15 (March 28, 2009)
- 2008 TC3 orbit and observationsatIAUMinor Planet Center
- 2008 TC3atNeoDyS-2, Near Earth Objects—Dynamic Site
- 2008 TC3atESA–space situational awareness
- 2008 TC3at theJPL Small-Body Database
