(454101) 2013 BP73

(454101) 2013 BP₇₃, provisional designation 2013 BP₇₃, is a sub-kilometer asteroid, classified as a near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 310 meters (1,020 ft) in diameter.^[3]

(454101) 2013 BP₇₃

Discovery[1][2]
Discovered by	Mount Lemmon Srvy.
Discovery site	Mount Lemmon Obs.
Discovery date	22 January 2013
Designations
MPC designation	(454101) 2013 BP73
Alternative designations	2013 BP73
Minor planet category	NEO · Apollo · PHA[1][3]
Orbital characteristics[3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc	12.72 yr (4,645 days)
Aphelion	2.1631 AU
Perihelion	0.4931 AU
Semi-major axis	1.3281 AU
Eccentricity	0.6287
Orbital period (sidereal)	1.53 yr (559 days)
Mean anomaly	218.36°
Mean motion	0° 38m 38.4s / day
Inclination	6.8507°
Longitude of ascending node	80.062°
Argument of perihelion	251.84°
Earth MOID	0.0021 AU (0.82 LD)
Physical characteristics
Mean diameter	0.31 km (estimate)[4]
Mass	4.0×1010 kg (assumed)[4]
Absolute magnitude (H)	20.4[3]

Description

From discovery until August 2013 when Sentry updated to planetary ephemeris (DE431), it had the 4th highest impact threat on the Palermo Technical Impact Hazard Scale.^[5] It was discovered on 22 January 2013 by the Mount Lemmon Survey at an apparent magnitude of 21 using a 1.5-meter (59 in) reflecting telescope.^[2] It has an estimated diameter of 310 meters (1,020 ft).^[4] Six Precovery images from April 2003 have been located.^[6] It was removed from the Sentry Risk Table on 3 January 2014.^[7]

It has an observation arc of 10 years with an uncertainty parameter of 2.^[3] Perturbations by Earth, Venus, and Mercury will increase the orbital uncertainty over time.^[8] When the asteroid only had an observation arc of 52 days, virtual clones of the asteroid that fit the uncertainty region in the known trajectory showed a 1 in 588,000 chance that the asteroid could impact Earth on 11 December 2096.^[4] With a 2096 Palermo Technical Scale of −3.42,^[4] the odds of impact by 2013 BP₇₃ in 2096 were about 2630 times less^[9] than the background hazard level of Earth impacts which is defined as the average risk posed by objects of the same size or larger over the years until the date of the potential impact.^[10] Using the nominal orbit, JPL Horizons shows that the asteroid will be 0.9 AU (130,000,000 km; 84,000,000 mi) from Earth on 11 December 2096.^[11] 2013 BP₇₃ made a close approach to Earth around 17 December 2018 that allowed a refinement to the known trajectory.^[8]

Numbering and naming

This minor planet was numbered by the Minor Planet Center on 25 December 2015 (M.P.C. 97517).^[12] As of 2018, it has not been named.^[1]