| Discovery [1] | |
|---|---|
| Discovered by | Richard A. Kowalski (Mount Lemmon Survey) |
| Discovery date | 10 March 2011 |
| Designations | |
| 2011 EO40 | |
| Orbital characteristics [3] [5] | |
| Epoch 9 August 2022 (JD 2459800.5) | |
| Uncertainty parameter 6 | |
| Aphelion | 2.5467 AU (380.98 Gm) |
| Perihelion | 0.76039 AU (113.753 Gm) |
| 1.65356 AU (247.369 Gm) | |
| Eccentricity | 0.54015 |
| 2.1264 yr (776.66 d) | |
| 169.9° | |
| 0° 27m 47.736s / day | |
| Inclination | 3.3591° |
| 50.249° | |
| 17.154° | |
| Earth MOID | 0.0482051 AU (7.21138 Gm) |
| Jupiter MOID | 2.79322 AU (417.860 Gm) |
| Physical characteristics | |
| Dimensions | 150–330 m [a] [6] |
| 21.5 [3] | |
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. [7] [8] [9]
2011 EO40 was discovered by Richard A. Kowalski on 10 March 2011 while observing for the Mount Lemmon Survey. [1] [10]
Its orbit is typical of Apollo asteroids and is characterized by significant eccentricity (0.54), low inclination (3.36º), and a semi-major axis of 1.65 AU. [10] Upon discovery, it was classified as an Earth crosser, a near-Earth asteroid (NEA) and a potentially hazardous asteroid (PHA) by the Minor Planet Center. It was listed on the Sentry Risk Table for less than one day. [11] Its orbit is in need of additional observations to determine if it is part of an asteroid family; as of October 2015 the orbit is determined using just twenty observations spanning an observation arc of 34 days. [3] 2011 EO40 has an absolute magnitude of 21.5, [3] which gives a characteristic diameter of about 200 metres (660 ft). [6]
Recent calculations indicate that this object is a plausible candidate to be the parent body of the Chelyabinsk superbolide, since its orbit is very similar to the computed, pre-impact path of the Chelyabinsk meteoroid. [7] [8] [9] It has relatively frequent close encounters with Venus, the Earth–Moon system, and Mars. It had a close encounter with Earth on 28 January 2011 at 0.0953 AU (14,260,000 km ; 8,860,000 mi ), [3] and it will have a nominal Earth approach on 23 September 2025 at about 0.06 AU (9,000,000 km; 5,600,000 mi). [3] Asteroid 2011 EO40 experiences close approaches to the Earth–Moon system following a rather regular pattern, every 17 years approximately due to the combined action of multiple secular resonances. [8]
Future opposition windows are: 7 June 2016 at magnitude 24.5, and 28 May 2018 at magnitude 24.6. The best observation window will be on 2–23 September 2025. [3] Depending on the Earth approach distance (0.04–0.12 AU), [3] it should be brighter than magnitude 19. [12]
(612358) 2002 JE9 (also written 2002 JE9) is an Apollo near-Earth asteroid and potentially hazardous object. It has a well determined orbit with an observation arc of 10 years and an Uncertainty Parameter of 1. It was removed from the Sentry Risk Table on 10 May 2002. 2002 JE9 was discovered on 6 May 2002 by the Lincoln Near-Earth Asteroid Research (LINEAR) project using a 1.0-metre (39 in) Reflecting telescope; at the time of discovery, the asteroid possessed an apparent magnitude of 19.1.
(152680) 1998 KJ9 is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group. Based on absolute magnitude, it is the third largest asteroid known to have passed closer than the Moon.
2013 BS45 (also written 2013 BS45) is a horseshoe companion to the Earth like 3753 Cruithne. Like Cruithne, it does not orbit the Earth in the normal sense and at times it is on the other side of the Sun, yet it still periodically comes nearer to the Earth in sort of halo orbit before again drifting away. While not a traditional natural satellite, it does not quite have normal heliocentric orbit either and these are sometimes called quasi-satellties or horseshoe orbits.
2006 JY26 is a near-Earth object that is also horseshoe companion to the Earth like 3753 Cruithne.
2012 FC71, also written 2012 FC71, is a small asteroid trapped in a Kozai resonance with the Earth.
2009 RR micro-asteroid, classified as near-Earth object of the Apollo group. It was discovered on 11 September 2009 by the Catalina Sky Survey at an apparent magnitude of 19.5 using a 0.68-meter (27 in) Schmidt–Cassegrain telescope. 2009 RR was the only asteroid discovered before 2014 that was predicted to potentially pass inside the orbit of the Moon during 2014. The asteroid has an estimated diameter of 26 meters (85 ft) and is listed on the Sentry Risk Table. It is not large enough to qualify as a potentially hazardous object.
2013 ND15 (also written 2013 ND15) is an asteroid that is a temporary trojan of Venus, the first known Venus trojan.
2014 OL339 (also written 2014 OL339) is an Aten asteroid that is a temporary quasi-satellite of Earth, the fourth known Earth quasi-satellite.
2013 LX28, is an asteroid, classified as near-Earth object of the Apollo group that is a temporary quasi-satellite of the Earth, the third known Earth quasi-satellite.
2015 SO2 (also written 2015 SO2) is an Aten asteroid that is a temporary horseshoe companion to the Earth, the ninth known Earth horseshoe librator. Prior to its most recent close encounter with our planet (2015 September 30) it was an Apollo asteroid.
2015 YQ1 (also written 2015 YQ1) is an Apollo asteroid that is a temporary horseshoe companion to the Earth, the twelfth known Earth horseshoe librator. It experienced a close encounter with the Earth on 2015 December 22 at 0.0037 AU.
2015 YA is a sub-kilometer asteroid, classified as near-Earth object of the Aten group, that is a temporary horseshoe companion to the Earth. It is the 11th known Earth horseshoe librator. Prior to a close encounter with the Earth on 15 December 2015, 2015 YA was an Apollo asteroid.
2017 FZ2 (also written 2017 FZ2) is a micro-asteroid and near-Earth object of the Apollo group that was a quasi-satellite of the Earth until March 23, 2017.
2017 DR109, is a micro-asteroid, classified as near-Earth object of the Apollo group and Aten group, respectively. It is currently trapped in a 1:1 mean motion resonance with the Earth of the horseshoe type. The object was first observed on 27 February 2017, by astronomers of the Catalina Sky Survey conducted at Mount Lemmon Observatory, Arizona, United States.
2017 SN16, is a sub-kilometer asteroid, classified as a near-Earth object of the Apollo group, approximately 90 meters (300 feet) in diameter. The object was first observed on 24 September 2017, by cometary discoverer Alex Gibbs with the Mount Lemmon Survey at Mount Lemmon Observatory, Arizona, in the United States. It forms an asteroid pair with 2018 RY7 and is currently trapped in a 3:5 mean motion resonance with Venus.
2018 RY7, is a small near-Earth object of the Apollo group. It is currently trapped in a 3:5 mean motion resonance with Venus. The object was first observed on 14 September 2018, by astronomer B. M. Africano with the Mount Lemmon Survey at Mount Lemmon Observatory, Arizona, United States.
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.
2020 PN1 is a sub-kilometer asteroid, classified as a near-Earth object of the Aten group, that is a temporary horseshoe companion to the Earth. There are dozens of known Earth horseshoe librators, some of which switch periodically between the quasi-satellite and the horseshoe co-orbital states.
2020 PP1 is a sub-kilometer asteroid, classified as a near-Earth object of the Apollo group, that is a temporary quasi-satellite of the Earth. There are over a dozen known Earth quasi-satellites, some of which switch periodically between the quasi-satellite and horseshoe co-orbital states.
2009 SH2 is a sub-kilometer near-Earth asteroid of the Aten group, discovered by the Siding Spring Survey at Siding Spring Observatory, Australia on 18 September 2009. It is in a co-orbital configuration with Earth, a type of 1:1 orbital resonance where the asteroid appears to librate around Earth's path in a horseshoe orbit when viewed in a corotating reference frame with Earth. The co-orbital state of 2009 SH2 is only temporary as it has entered it about 30 years ago and will leave it in about 100 years into the future.
2011 in space | ||
|---|---|---|
2012 » | ||
Space probe launches  |
|    |
| Selected NEOs | ||
| Exoplanets |
| |
| Discoveries | ||
| Novae | ||
| Comets | ||
| Space exploration | ||
