Discovery
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Discovered by | LINEAR |
Discovery date | August 24, 2003 |
Designations
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Alternate name(s) | none |
Minor planet category |
Apollo asteroid |
Epoch October 22, 2004 (JD 2453300.5) | |
Aphelion | 192.756 Gm (1.288 AU) |
Perihelion | 132.005 Gm (0.882 AU) |
Semi-major axis | 162.380 Gm (1.085 AU) |
Eccentricity | 0.187 |
Orbital period | 413.057 d (1.13 a) |
Average orbital speed | 28.34 km/s |
Mean anomaly | 290.754° |
Inclination | 62.102° |
Longitude of ascending node | 1.014° |
Argument of perihelion | 105.042° |
Physical characteristics
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Dimensions | 1.24 km |
Mass | 2.0×1012 kg |
Mean density | 2.0? g/cm³ |
Equatorial surface gravity | 0.0003 m/s² |
Escape velocity | 0.0007 km/s |
Rotation period | ? d |
Albedo | 0.10? |
Temperature | ~267 K |
Spectral type | ? |
Absolute magnitude (H) | 17.3 |
(143649) 2003 QQ47 (also written 2003 QQ47) is an asteroid which became briefly notable upon its discovery in late August 2003 when media outlets played up a preliminary report that it had a 1:250,000 chance of colliding with Earth on March 21, 2014.[1]
It was added to the Sentry Risk Table on 30 August 2003.[1] It was removed from the Sentry Risk Table on 14 September 2003.[2]
It is now known that 2003 QQ47 will safely pass 0.1283 AU (19,190,000 km; 11,930,000 mi) from the Earth on 2014-Mar-26.[3][4]
A NASA spokesman said,
(143649) 2003 QQ47 has a diameter of approximately 1.24 km, and a mass of approximately 2.0×1012 kg. If it were to hit the Earth, it would be a major event, with an energy of approximately 350,000 megatons of TNT (1.5 ZJ), enough to cause global damage.
Dr. Sara Russell, a meteorite researcher at London's Natural History Museum, told the BBC that she was not worried that (143649) 2003 QQ47 would be a danger.
As a result of the press coverage of asteroids such as (143649) 2003 QQ47, astronomers are now planning to re-word the Torino scale, or to phase it out completely in favour of a scale which is less likely to generate false alarms which may reduce public confidence in genuine alerts.
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