Discovery [1] [2] | |
---|---|
Discovery site | Pan-STARRS at the Haleakala Observatory, Hawaii |
Discovery date | June 23, 2015 |
Designations | |
2015 ME131 | |
2020 RX8 | |
[1] [2] [3] | |
Orbital characteristics [3] | |
Epoch 2020-Dec-17 (JD 2459200.5) | |
Uncertainty parameter 2 | |
Observation arc | 5.3 years [4] |
Aphelion | 0.98964 AU (Q) |
Perihelion | 0.64282 AU (q) |
0.81623 AU (a) | |
Eccentricity | 0.21245 (e) |
0.74 years | |
358.69° (M) | |
Inclination | 33.645° (i) |
317.78° (Ω) | |
156.86° (ω) | |
Earth MOID | 0.0458 AU (6,850,000 km) |
Jupiter MOID | 4.01 AU (600,000,000 km) |
Physical characteristics | |
Mean diameter | 400 m [2] 500 m [4] |
19.5 [3] | |
2015 ME131 (also written 2015 ME131) was a lost asteroid [5] 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), [2] 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. [3] 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 [1] and had a solar elongation of 68 degrees. [6]
This asteroid was in both the Risk list [2] and the Priority List of the European Space Agency (ESA) - Space Situational Awareness (SSA). This asteroid was also in the Sentry list [7] of the Jet Propulsion Laboratory (JPL) - Center for Near Earth Object Studies (CNEOS). According to the Sentry List, of the possible close encounters with Earth in the foreseeable future, an encounter on August 18, 2020 had the highest Palermo Technical Impact Hazard Scale value. [4]
According to the Near Earth Objects Dynamic Site (NEODyS), of the possible close encounters with Earth in the foreseeable future, an encounter on August 10, 2025 is the most likely. [8] This encounter has a minimum possible distance of zero, meaning that an impact onto Earth is possible.
NEODyS is an Italian service that provides information on near-Earth objects with a Web-based interface. It is based on a continually and (almost) automatically maintained database of near earth asteroid orbits. This site provides a number of services to the NEO community. The main service is an impact monitoring system (CLOMON2) of all near-Earth asteroids covering a period until the year 2100.
(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.
(85640) 1998 OX4, also written 1998 OX4, is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group.
2013 TV135 is an Apollo near-Earth asteroid estimated to have a diameter of 450 meters (1,480 ft). On 16 September 2013, it passed about 0.0448 AU (6,700,000 km; 4,160,000 mi) from Earth. On 20 September 2013, it came to perihelion (closest approach to the Sun). The asteroid was discovered on 12 October 2013 by Ukrainian amateur astronomer Gennadiy Borisov with a custom 0.2-meter (7.9 in) telescope using images dating back to 8 October 2013. It was rated level 1 on the Torino Scale from 16 October 2013 until JPL solution 26 on 3 November 2013. It reached a Palermo Technical Impact Hazard Scale rating of -0.73. It was removed from the JPL Sentry Risk Table on 8 November 2013 using JPL solution 32 with an observation arc of 27 days.
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.
2014 OO6 (also written 2014 OO6) is an Apollo near-Earth asteroid discovered in 2014 and was the most dangerous one discovered in 2014 that remained on the Sentry Risk Table as of early December 2014. The asteroid is estimated to be roughly 75 meters (246 ft) in diameter and had a 1 in 83,000 chance of impacting Earth on 11 January 2051. However, the nominal best-fit orbit shows that 2014 OO6 will be 1.5 AU (220,000,000 km; 140,000,000 mi) from Earth on 11 January 2051.
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.
2006 QV89 (also written 2006 QV89) is an Apollo near-Earth asteroid roughly 30 meters (100 feet) in diameter. It was discovered on 29 August 2006 when the asteroid was about 0.03 AU (4,500,000 km; 2,800,000 mi) from Earth and had a solar elongation of 150 degrees.
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 40 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.
2016 NL56 (also written 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 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 DB120 (also written 2017 DB120) 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 February 25, 2017, when the asteroid was less than 1 AU from Earth and had a solar elongation of 169°.
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.
2020 XR is an Apollo near-Earth object and potentially hazardous asteroid roughly 390 meters in diameter. With a 5-day observation arc it was briefly listed as having a 1 in 11,000 chance of impacting Earth on 1 December 2028 placing it at the top of the Sentry Risk Table with a Palermo scale rating of -0.70.