Discovery [1] | |
---|---|
Discovered by | S. S. Sheppard |
Discovery site | Cerro Tololo Observatory |
Discovery date | 13 January 2022 |
Designations | |
2022 AP7 | |
NEO · Apollo · PHA [2] | |
Orbital characteristics [3] | |
Epoch 9 August 2022 (JD 2459800.5) | |
Uncertainty parameter 1 | |
Observation arc | 4.86 yr (1,774 days) |
Earliest precovery date | 20 December 2017 |
Aphelion | 5.015 AU |
Perihelion | 0.833 AU |
2.924 AU | |
Eccentricity | 0.7151 |
5.00 yr [3] | |
25.857° | |
0° 11m 49.647s / day | |
Inclination | 13.835° |
192.377° | |
30 March 2022 | |
113.590° | |
Earth MOID | 0.04716 AU (7,055,000 km; 18.35 LD) |
Mars MOID | 0.07344 AU (10,986,000 km; 28.58 LD) [2] |
Jupiter MOID | 1.19258 AU (178.407 Gm) |
Physical characteristics | |
Mean diameter | 1.1–2.3 km [4] [lower-alpha 1] 1.2 km [5] [lower-alpha 2] |
17.1±0.2 [4] [3] 17.3 (MPC) [2] | |
2022 AP7 is a kilometer-sized Apollo asteroid and potentially hazardous object orbiting between Venus and Jupiter. It was discovered on 13 January 2022 by Scott Sheppard at Cerro Tololo Observatory. [1] Based on its absolute magnitude (H), 2022 AP7 is likely the largest potentially hazardous object identified in the eight years prior to its 2022 discovery. [4] [lower-alpha 3]
2022 AP7 was discovered as part of Sheppard's twilight survey for near-Earth asteroids interior to Earth and Venus, using Cerro Tololo Observatory's Dark Energy Camera. [1] Notable discoveries from this survey include the Atira asteroids 2021 LJ4 and 2021 PH27 , the latter of which holds the record for the shortest orbital period of any known asteroid as of 2022 [update] . [4]
2022 AP7 is considered "potentially hazardous" only because of its large size and low Earth minimum orbit intersection distance (MOID) just within 0.05 AU (7.5 million km ; 19 LD ). [3] [4] However, the asteroid does not currently make notable close approaches to Earth because it is in a 1:5 near orbital resonance with Earth, [8] which means it nearly takes exactly 5.0 years to orbit the Sun in a highly elliptical orbit. [3] This resonance regularly puts it in positions where observational conditions are unfavorable; the asteroid is obscured by the Sun's glare when it becomes brightest near perihelion at low solar elongations and can be fainter at opposition when it is farther from Earth. [4] As a result, 2022 AP7 could only be efficiently searched at twilight when at its brightest; the asteroid was 45 degrees from the Sun and 1.9 AU from Earth when it was discovered. [4] [9] The asteroid made its closest approach 1.5 AU from Earth in March 2022. The asteroid will not come this close to Earth again until March 2027. [10] By May 2022, when the asteroid was 1 AU from the Sun and near the ecliptic, Earth was on the other side of the Sun, 1.9 AU from the asteroid. [11]
The asteroid is not risk listed. 2022 AP7's orbit is well-determined and will guarantee only distant approaches beyond 1.1 AU (160 million km; 430 LD) of Jupiter over the next 146 years. [3] [8] The asteroid will also pass 0.16 AU (24 million km; 62 LD) from Mars on 9 May 2107. [12] Nominally the asteroid will not approach 1 AU from Earth until April 2332. [13] Over the next several centuries if not thousands of years, repeated perturbations by these encounters will eventually break the 1:5 near orbital resonance of 2022 AP7, potentially leading to an impact with Earth. [14]
Object | Date | Nearest approach (AU) |
---|---|---|
Mars | 2107-05-09 | 0.16 AU (24 million km ; 62 LD ) [12] |
Venus | 2147-04-22 | 0.23 AU (34 million km; 90 LD) [15] |
Mercury | 2062-03-07 | 0.44 AU (66 million km; 170 LD) [16] |
Sun | 2057-03-26 | 0.82 AU (123 million km; 320 LD) [17] |
Jupiter | 2109-09-30 | 1.19 AU (178 million km; 460 LD) [3] |
Earth | 2052-03-12 | 1.37 AU (205 million km; 530 LD) [18] |
4769 Castalia is a near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 1.4 kilometers in diameter and was the first asteroid to be modeled by radar imaging. It was discovered on 9 August 1989, by American astronomer Eleanor Helin (Caltech) on photographic plates taken at Palomar Observatory in California. It is named after Castalia, a nymph in Greek mythology. It is also a Mars- and Venus-crosser asteroid.
4486 Mithra, is an eccentric asteroid and suspected contact-binary, classified as near-Earth object and potentially hazardous asteroid, approximately 2 kilometers in diameter. It belongs to the Apollo group of asteroids and is a relatively slow rotator.
(524522) 2002 VE68, provisional designation 2002 VE68, is a sub-kilometer sized asteroid and temporary quasi-satellite of Venus. It was the first such object to be discovered around a major planet in the Solar System. In a frame of reference rotating with Venus, it appears to travel around it during one Venerean year but it actually orbits the Sun, not Venus.
2007 VK184 is a sub-kilometer asteroid, classified as a near-Earth object of the Apollo group, and estimated to be approximately 130 meters (430 ft) in diameter. It was listed on the Sentry Risk Table with a Torino Scale rating of 1 for a potential impactor in June 2048. It was removed from the Sentry Risk Table on 28 March 2014.
A potentially hazardous object (PHO) is a near-Earth object – either an asteroid or a comet – with an orbit that can make close approaches to the Earth and which is large enough to cause significant regional damage in the event of impact. They are conventionally defined as having a minimum orbit intersection distance with Earth of less than 0.05 astronomical units and an absolute magnitude of 22 or brighter, the latter of which roughly corresponds to a size larger than 140 meters. More than 99% of the known potentially hazardous objects are no impact threat over the next 100 years. As of September 2022, just 17 of the known potentially hazardous objects listed on the Sentry Risk Table could not be excluded as potential threats over the next hundred years. Over hundreds if not thousands of years though, the orbits of some "potentially hazardous" asteroids can evolve to live up to their namesake.
1994 WR12 is an asteroid and near-Earth object approximately 130 meters (430 feet) in diameter. As a member of the Aten group almost all of its orbit is closer to the Sun than Earth is. On 24 November 1994 it passed about 374100 km from the Moon. First imaged at Kitami Observatory on 26 November 1994, it was discovered two nights later by American astronomer Carolyn S. Shoemaker at Palomar Observatory on 28 November 1994. The asteroid then went unobserved from 1994 until it was recovered by Mauna Kea in March 2016. It was removed from the Sentry Risk Table on 2 April 2016.
Minimum orbit intersection distance (MOID) is a measure used in astronomy to assess potential close approaches and collision risks between astronomical objects. It is defined as the distance between the closest points of the osculating orbits of two bodies. Of greatest interest is the risk of a collision with Earth. Earth MOID is often listed on comet and asteroid databases such as the JPL Small-Body Database. MOID values are also defined with respect to other bodies as well: Jupiter MOID, Venus MOID and so on.
343158 Marsyas (prov. designated2009 HC82) is an asteroid on a retrograde orbit, classified as a large near-Earth object of the Apollo group. It may be an extinct comet or damocloid asteroid. The asteroid was discovered on 29 April 2009, by astronomers with the Catalina Sky Survey at the Catalina Station near Tucson, Arizona, in the United States. Approximately 2 kilometers (1.2 miles) in diameter, it makes many close approaches to Earth, Venus, and Mars at a very high relative velocity. It was named after the satyr Marsyas from Greek mythology.
(467336) 2002 LT38, is a sub-kilometer asteroid and suspected tumbler, classified as a near-Earth object and potentially hazardous asteroid of the Aten group, approximately 240 meters (790 ft) in diameter. It was discovered on 12 June 2002, by astronomers of the Lincoln Near-Earth Asteroid Research at the Lincoln Laboratory's Experimental Test Site near Socorro, New Mexico, in the United States.
(7482) 1994 PC1 is a stony asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 1.1 kilometers in diameter. It was discovered on 9 August 1994, by astronomer Robert McNaught at the Siding Spring Observatory in Coonabarabran, Australia. With an observation arc of 47 years it has a very well known orbit and was observed by Goldstone radar in January 1997. The 2022 approach has been observed every month since August 2021.
2011 EO40 is an asteroid, classified as a near-Earth object and a potentially hazardous asteroid of the Apollo group. It is a possible candidate for the parent body of the Chelyabinsk superbolide.
(456938) 2007 YV56, provisional designation 2007 YV56, is a sub-kilometer asteroid on an eccentric orbit, classified as a near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 190–360 meters (620–1,200 ft) in diameter. It was discovered on 31 December 2007, by astronomers of the Catalina Sky Survey conducted at the Catalina Station in Arizona, United States.
2014 JO25 is a near-Earth asteroid. It was discovered in May 2014 by astronomers at the Catalina Sky Survey near Tucson, Arizona - a project of NASA's NEO (Near Earth Object) Observations Program in collaboration with the University of Arizona.
(52768) 1998 OR2 (provisional designation 1998 OR2) is an asteroid on an eccentric orbit, classified as a near-Earth object and potentially hazardous asteroid of the Amor group, with a diameter of 2 kilometers (1.2 mi). It was discovered on 24 July 1998, by astronomers of the Near-Earth Asteroid Tracking (NEAT) program at the Haleakala Observatory, Hawaii. It is one of the brightest and therefore largest potentially hazardous asteroids known to exist. With an observation arc of 35 years, the asteroid has a well-determined orbit, and its trajectory is well known through the year 2197. The asteroid's orbit is only potentially hazardous on a time scale of thousands of years.
2018 VP1 is an Apollo near-Earth asteroid roughly 2 meters (7 feet) in diameter. The asteroid had a 0.41% chance (1 in 240) of impacting Earth on 2 November 2020 01:12 UT. It was discovered on 3 November 2018 when it was about 0.003 AU (450,000 km; 280,000 mi) from Earth and had a solar elongation of 165 degrees. The asteroid has a short 12.9 day observation arc. It was last observed on 16 November 2018 by the European Southern Observatory Very Large Telescope at apparent magnitude 26 pushing the telescope close to the limiting magnitude.
(501647) 2014 SD224 is an Aten near-Earth asteroid around 150 meters (490 feet) in diameter. It was discovered on 22 September 2014 when the asteroid was 0.29 AU (43 million km; 110 LD) from Earth and had a solar elongation of 123 degrees. The glare of the Sun had masked the approach of the asteroid as it passed closest approach to Earth on 11 August 2014. The asteroid now has a 6-year observation arc and a well-determined orbit. It also makes close approaches to Venus.
2020 LD is an Apollo near-Earth asteroid roughly 140 meters in diameter. It was discovered on 7 June 2020 when the asteroid was about 0.03 AU from Earth and had a solar elongation of 154 degrees. The glare of the Sun had masked the approach of the asteroid since November 2019. The asteroid passed closest approach to Earth on 5 June 2020 at a distance of 0.002 AU. The close approach distance is now known with an accuracy of roughly ± 1000 km. This is the largest asteroid to pass closer than the Moon this year and possibly the largest since (308635) 2005 YU55 in November 2011. The asteroid makes close approaches to Mercury, Venus, Earth, and Mars. It will be brighter than apparent magnitude 24 until 18 July 2020.
(231937) 2001 FO32 is a near-Earth asteroid classified as a potentially hazardous asteroid of the Apollo group. With an estimated diameter around 550 m (1,800 ft), it was discovered by the Lincoln Near-Earth Asteroid Research at Socorro, New Mexico on 23 March 2001. The asteroid safely passed by Earth on 21 March 2021 16:03 UTC from a closest approach distance of 0.0135 AU (2.02 million km; 1.25 million mi), or 5.25 lunar distances (LD). During the day before closest approach, 2001 FO32 reached a peak apparent magnitude of 11.7 and was visible to ground-based observers with telescope apertures of at least 20 cm (8 in). It is the largest and one of the fastest asteroids to approach Earth within 10 LD (3.8 million km; 2.4 million mi) in 2021.
2021 PH27 is a near-Earth asteroid of the Atira group. It was discovered by Scott Sheppard using the Dark Energy Survey's DECam imager at NOIRLab's Cerro Tololo Inter-American Observatory on 13 August 2021. 2021 PH27 has the smallest semi-major axis and shortest orbital period among all known asteroids as of 2021, with a velocity at perihelion of 106 km/s (240,000 mph). It also has the largest value of the relativistic perihelion shift, 1.6 times that of Mercury. With an absolute magnitude of 17.7, the asteroid is estimated to be larger than 1 kilometer (0.6 miles) in diameter.
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At nearly 1.5 kilometers wide, it's the largest such asteroid discovered in eight years.
'It remains very far from Earth, kind of locked in a resonance that keeps it as being actually one of the most distant of the asteroids that we categorize as potentially hazardous.' ... 2022 AP7 is only projected to have close approaches to Mars and Jupiter in the next 145 years [not Earth].