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(292220) 2006 SU49, provisional designation 2006 SU49, is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group that had a small chance of impacting Earth in 2029.
(276033) 2002 AJ129, provisional designation 2002 AJ129, is a Mercury-crossing asteroid. It has the ninth-smallest perihelion of all numbered asteroids, after asteroids such as 2000 BD19, 2004 UL, and 2008 XM. It makes close approaches to all of the inner planets and asteroid 4 Vesta. The asteroid is estimated to be between 0.5–1.2 kilometers (0.3–0.7 mi) across. In January 2018 there was much media hype about this asteroid being classified as a potentially hazardous asteroid, although there is no known threat of an impact for hundreds if not thousands of years. The media has compared the size of the asteroid to the Burj Khalifa in Dubai.
2010 AU118 (also written 2010 AU118) is a potential Amor near-Earth asteroid with an observation arc of only 1.4 days and thus a poorly determined orbit. It was announced on 27 May 2010 based on images taken by the Wide-field Infrared Survey Explorer (WISE) on 13–15 January 2010. It was removed from the Sentry Risk Table on 14 June 2014 as a result of an update to the Sentry software. Another software update restored it to the Sentry Risk Table in 2017. It was again removed from the sentry list on 3 October 2018.
(163132) 2002 CU11, provisional designation 2002 CU11, is a bright, sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group. Based on absolute magnitude, it is the second largest asteroid known to have passed closer than the Moon.
2000 EM26 is a sub-kilometer near-Earth object and potentially hazardous asteroid of the Aten group, approximately 110 meters (360 feet) in diameter. It was first observed by astronomers of the LINEAR program on 5 March 2000 and followed until 14 March 2000, by which time it had dimmed to apparent magnitude 20 and was 40° from the Moon. By 17 March 2000 it was only 4 degrees from a 90% waxing gibbous moon. It has never been listed on the Sentry Risk Table because none of the potential orbital solutions create a risk of impact in the next ~100 years. The asteroid safely passed Earth on 17–18 February 2014. Due to a then-poorly determined orbit, the asteroid may have been significantly further from Earth and dozens of degrees from where the telescope was pointed during the 2014 approach.
2012 FN is an Apollo asteroid and a near-Earth object that has a 1 in 4 billion chance of impacting Earth on 7 March 2113. It is estimated to be 5 meters in diameter, which means that it poses no threat if it impacts Earth. An impact would have the kinetic energy of about 3 kt of TNT, and would probably result in an air burst in the upper atmosphere. It is the least threatening asteroid listed on the Sentry Risk Table. The very short observation arc of only 3 hours results in a very poorly constrained orbit, and it could just as easily be 2 AU from Earth on 7 March 2113.
2007 VE191 is a sub-kilometer asteroid, classified as near-Earth asteroid of the Apollo group that was listed on the Sentry Risk Table.
2014 XL7 is a near-Earth object and Apollo asteroid, approximately 230 meters (750 feet) in diameter. It was the most dangerous potentially hazardous asteroid on Sentry Risk Table upon its discovery by the Mount Lemmon Survey in December 2014. At the time, the asteroid had a cumulative 1 in 83000 chance of impacting Earth on 4–5 June between the years 2048 and 2084. After the object's observation arc had been extended to 35 days, it was removed from the Sentry Risk Table on 15 January 2015. Since then the asteroid's orbit has been secured. Although it has an Earth minimum orbit intersection distance of less than one lunar distance, there are no projected close encounters with Earth in the foreseeable future, with its closest passage to occur in May 2046, still millions of kilometers away.
2015 AZ43 (also written 2015 AZ43) is an Apollo near-Earth asteroid roughly 70 meters in diameter. On 10 February 2015 with a 29.5-day observation arc, it showed a 1 in 5,880 chance of impacting Earth on 27 February 2107. However, the NEODyS nominal best-fit orbit shows that 2015 AZ43 will be 2.8 AU (420,000,000 km; 260,000,000 mi) from Earth on 27 February 2107. A (non-impacting) Earth close approach in 2056 makes future trajectories diverge. It was removed from the JPL Sentry Risk Table on 23 February 2015 using JPL solution 26 with an observation arc of 40 days that included radar data.
2013 TX68 is an Apollo asteroid and near-Earth object discovered on 6 October 2013 by the Catalina Sky Survey, during which it was near a close approach of 5.4 Lunar distances (LD) from the Earth. The asteroid only has a 10-day observation arc which makes long-term predictions of its position less certain. It was observed for three days as it approached Earth in the night sky starting with the sixth of October, 2013. Then it became unobservable by being between the Earth and the Sun, then not recovered due to its small size and dimness. Precovery images by Pan-STARRS from 29 September 2013 were announced on 11 February 2016 that extended the observation arc to 10 days. It was removed from the Sentry Risk Table on 11 February 2016, so there is no risk of impact from this object for the next hundred years or more. The asteroid was last observed on 9 October 2013.
2018 LF16 is a small Mars crossing asteroid roughly 213 m (699 ft) in diameter. It was first observed by astronomers with the Pan-STARRS survey at Haleakala Observatory on 14 June 2018. It was removed from the Sentry Risk Table on 29 July 2021. With an observation arc of 15 years the orbit is very well known and it does not make any notable approaches to Earth.
2011 ES4 (also written 2011 ES4) is an Apollo near-Earth asteroid roughly 22–49 meters (72–160 feet) in diameter. It was first observed on 2 March 2011 when the asteroid was about 0.054 AU (8,100,000 km; 5,000,000 mi) from Earth and had a solar elongation of 159 degrees. It passed closest approach to Earth on 13 March 2011. Before the 2020 approach, the asteroid had a short observation arc of 4 days and had not been observed since March 2011. The asteroid was expected to pass within 1 lunar distance of Earth in early September 2020, but did not. There was no risk of a 2020 impact because the line of variation (LOV) did not pass through where Earth would be, and the closest possible 2020 Earth approach was about 0.00047 AU (70,000 km; 44,000 mi). One line of variation showed the asteroid passing closest to Earth on 5 September 2020 at 0.06 AU (9,000,000 km; 5,600,000 mi) with a magnitude of 23, which would place it near the limiting magnitude of even the best automated astronomical surveys.
1979 XB is a lost asteroid with a short observation arc of 3.9 days that cannot be recovered with targeted observations and awaits serendipitous survey observations. It is classified as a near-Earth object and potentially hazardous asteroid of the Apollo group and is estimated to be 660 meters in diameter. The unnumbered minor planet has a poorly constrained orbit and has not been observed in 45 years. It has been listed on the Sentry Risk Table since the list started in 2002. With a cumulative Palermo Technical Impact Hazard Scale of −2.72, the poorly known orbit and assumed size place 1979 XB third on an unconstrained listing of the Sentry Risk Table.
2015 ME131 (also written 2015 ME131) was a lost asteroid and a Near-Earth object (NEO). It is an Atira asteroid, which is by far the smallest group of near-Earth objects. This makes it an interior-Earth object (IEO), meaning that it has an orbit entirely confined within Earth's orbit. It was recovered on September 15, 2020 as 2020 RX8 which has extended the observation arc from 1.8 days to 5 years. It was removed from the Sentry Risk Table on February 15, 2021 after the two orbits were linked together. It was first observed on June 23, 2015, when the asteroid was more than 1 AU from Earth and had a solar elongation of 68 degrees.
(696513) 2016 NL56 (provisional designation 2016 NL56) is a near-Earth object (NEO) and a potentially hazardous object (PHA), meaning that it has an orbit that can make close approaches to the Earth and large enough to cause significant regional damage in the event of impact. It is an Apollo asteroid, meaning that it is an Earth-crossing asteroid that has an orbit larger than the orbit of the Earth. It was first observed on 12 July 2016, when the asteroid was more than 1 AU from Earth and had a solar elongation of 163 degrees.
2017 QC36 is a near-Earth object and a potentially hazardous asteroid of the Aten group, It measures approximately 200 meters (660 feet) in diameter and was briefly observed by the Wide-field Infrared Survey Explorer on 18 August 2017 before it became a lost asteroid on the following day. It was later recovered in 2021 from archival Pan-STARRS and Cerro Tololo observations.
2017 MZ8 (also written 2017 MZ8) is a near-Earth object and a potentially hazardous asteroid, meaning that it has an orbit that can make close approaches to the Earth and large enough to cause significant regional damage in the event of impact. It is an Apollo asteroid, meaning that it is an Earth-crossing asteroid that has an orbit larger than the orbit of the Earth. It was first observed on 22 June 2017, when the asteroid was about 1 AU from Earth and had a solar elongation of 131 degrees.
2017 SG33 (also written 2017 SG33) is a near-Earth object, meaning that it has an orbit which brings it into proximity with Earth. It is an Amor asteroid, meaning that its orbit does not cross Earth's orbit, but its perihelion is close to, but greater than, the aphelion of Earth. It was first observed on 25 September 2017, when the asteroid was less than 1 AU from Earth and had a solar elongation of 169°.
2020 VV is an Apollo near-Earth asteroid roughly 12 meters in diameter. On 20 November 2020, the asteroid had a 4.4% chance of impacting Earth on 12 October 2033 11:43 UT. As of mid-December 2020, the asteroid has a modest 61 day observation arc. The nominal Earth approach is on 17 October 2033 at a distance of 0.009 AU, but the line of variations (LOV) is only known with an accuracy of ±22 hours. The line of variations allows the asteroid to come as close as 0.006 AU or pass as far away as 0.01 AU. With a diameter range of 10–22 meters the asteroid could be as large as the Chelyabinsk meteor.
2022 AE1 is a Tunguska event-sized asteroid, classified as a near-Earth object of the Apollo group, approximately 70 meters (230 feet) in diameter. It was discovered by the Mount Lemmon Survey on 6 January 2022, when it was 0.09 AU (13 million km) from Earth. On 9 January 2022 with an observation arc of 3 days, it was rated with a Torino scale of 1 for a virtual impactor on 4 July 2023 16:28 UTC. Nominal approach is expected to occur 1 July 2023 01:13 ± 1 day. With a Palermo scale rating of as high as –0.66 at the European Space Agency on 11 January 2022, the odds of impact peaked at about 4.6 times less than the background hazard level. NEODyS was the first risk-page to drop to Torino scale 0 on 12 January 2022 followed by ESA on 13 January 2022, but by January 14 both returned to Torino scale 1. On 14 January 2022 the waxing gibbous moon was as little as 3 degrees from the asteroid delaying observations of the asteroid from January 12–19. On 20 January 2022 with a 16-day observation arc, using JPL #11 the Sentry Risk Table dropped the asteroid to Torino scale 0 and then later that day JPL #12 resulted in it being removed from the risk table.
References
- 1 2 3 4 5 6 "2017 DB120". Minor Planet Center. Retrieved 11 September 2020.
- 1 2 3 4 5 "JPL Small-Body Database Browser: (2017 DB120)" (2017-02-27 last obs.). Jet Propulsion Laboratory . Retrieved 11 September 2020.
- 1 2 3 4 5 "Sentry: Earth Impact Monitoring - Object Details 2017 DB120". Jet Propulsion Laboratory . Retrieved 6 September 2020.
- 1 2 3 "ESA space situational awareness 2017DB120". European Space Agency . Retrieved 6 September 2020.
- ↑ "JPL HORIZONS Web-Interface (2017 DB120)". Jet Propulsion Laboratory . Retrieved 6 September 2020.
- ↑ "NEODyS-2 Risk List". SpaceDys . Retrieved 6 September 2020.
- ↑ "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 11 September 2020.
- ↑ "Sentry: Earth Impact Monitoring - Impact Risk Data". Jet Propulsion Laboratory . Retrieved 6 September 2020.
- ↑ "NEODyS-2 - Near Earth Objects - Dynamic Site - 2017DB120 - Close Approaches". SpaceDys . Retrieved 6 September 2020.
