| Discovery1 | |
|---|---|
| Discovered by | Richard A. Kowalski (Mount Lemmon Survey) |
| Discovery date | 10 March 2011 |
| Designations | |
| Orbital characteristics35 | |
| Epoch 21 November 2025 (JD 2461000.5) | |
| Uncertainty parameter 1 | |
| Aphelion | 2.5481 AU (381.19 Gm) |
| Perihelion | 0.76020 AU (113.724 Gm) |
| 1.65416 AU (247.459 Gm) | |
| Eccentricity | 0.54043 |
| 2.1275 yr (777.08 d) | |
| 5.6° | |
| 0° 27m 47.772s / day | |
| Inclination | 3.3615° |
| 50.172° | |
| 17.230° | |
| Earth MOID | 0.048041 AU (7.1868 Gm) |
| Jupiter MOID | 2.79521 AU (418.157 Gm) |
| Physical characteristics | |
| Dimensions | 120–280 m[a]6 |
| 21.93 | |
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.789
Discovery, orbit and physical properties
2011 EO40 was discovered by Richard A. Kowalski on 10 March 2011 while observing for the Mount Lemmon Survey.110
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
Relationship to the Chelyabinsk superbolide
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.789 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
Visibility
2011 EO40 had opposition windows on 7 June 2016 at magnitude 24.5, and 28 May 2018 at magnitude 24.6 but wasn't observed during either opposition.10 The asteroid was recovered on 15 August 2025 by Pan-STARRS.12 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 19.13
References
References
- Discovery MPEC
- List Of Apollo Minor Planets
- "JPL Small-Body Database Browser: (2011 EO40)". Jet Propulsion Laboratory. Retrieved 2 August 2022.
- "List Of The Potentially Hazardous Asteroids (PHAs)". Minorplanetcenter.net. Retrieved 27 June 2014.
- NEODyS-2 on 2011 EO40 Retrieved 2013-07-31
- Asteroid Size Estimator
- de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl (21 November 2013). "The Chelyabinsk superbolide: a fragment of asteroid 2011 EO40?". Monthly Notices of the Royal Astronomical Society: Letters. 436 (1): L15–L19. arXiv:1307.7918. Bibcode:2013MNRAS.436L..15D. doi:10.1093/mnrasl/slt103.
- de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl (1 September 2014). "Reconstructing the Chelyabinsk event: pre-impact orbital evolution". Monthly Notices of the Royal Astronomical Society: Letters. 443 (1): L39–L43. arXiv:1405.7202. Bibcode:2014MNRAS.443L..39D. doi:10.1093/mnrasl/slu078.
- de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl; Aarseth, S. J. (10 October 2015). "Chasing the Chelyabinsk asteroid N-body style". The Astrophysical Journal. 812 (1): 26 (22 pp). arXiv:1508.05907. Bibcode:2015ApJ...812...26D. doi:10.1088/0004-637X/812/1/26.
- MPC data on 2011 EO40
- "Observations of small Solar-System bodies". hohmanntransfer. 11 March 2011. Archived from the original on 23 November 2020. Retrieved 6 August 2013. (2.7e-07 = 1 in 3,704,000 chance)
- "MPEC 2025-Q20 : 2011 EO40". www.minorplanetcenter.net. Retrieved 25 February 2026.
- "2011EO40 Ephemerides for 23 August 2025 through 30 September 2025". NEODyS (Near Earth Objects – Dynamic Site). Retrieved 4 July 2014.
External links
External links
- 2011 EO40 data at MPC
- MPEC 2011-E59 : 2011 EO40 (Discovery MPEC)
- Russian meteor may have gangmates in tow, Nature, short article
- Has the Chelyabinsk Meteor Parent Asteroid Been Found?, Bad Astronomy blog entry
- 2011 EO40 at NeoDyS-2, Near Earth Objects—Dynamic Site
- 2011 EO40 at ESA–space situational awareness
- 2011 EO40 at the JPL Small-Body Database