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.[5] It was discovered by the Mount Lemmon Survey on 6 January 2022, when it was 0.09 AU (13 million km) from Earth.[1] 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.[3][a] Nominal approach is expected to occur 1 July 2023 01:13 ± 1 day.[2][b] With a Palermo scale rating of as high as –0.66 at the European Space Agency on 11 January 2022,[6] the odds of impact peaked at about 4.6[c] times less than the background hazard level.[d] NEODyS was the first risk-page to drop to Torino scale 0 on 12 January 2022[7] followed by ESA on 13 January 2022,[6] 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.[8] 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.[9][10]
| Discovery[1] | |
|---|---|
| Discovered by | Mount Lemmon Survey |
| Discovery site | Mount Lemmon Obs. |
| Discovery date | 6 January 2022 |
| Designations | |
| 2022 AE1 | |
| Orbital characteristics[2] | |
| Epoch 2022-Jan-21 (JD 2459600.5) | |
| Uncertainty parameter 7 | |
| Observation arc | 20 days |
| Aphelion | 2.27 AU (Q) |
| Perihelion | 0.667 AU (q) |
| 1.47 AU (a) | |
| Eccentricity | 0.547 (e) |
| 1.78 years | |
| 39° (M) | |
| Inclination | 6.3° (i) |
| 102.2° (Ω) | |
| 10 November 2021 | |
| 268.3° (ω) | |
| Earth MOID | 0.00007 AU (10 thousand km) |
| Jupiter MOID | 3.2 AU (480 million km) |
| Physical characteristics | |
| |
| 23.49[4] | |
| Observation arc (in days) |
JPL Horizons nominal geocentric distance (AU) |
uncertainty region (3-sigma) |
Impact probability (1 in) |
Torino scale |
|---|---|---|---|---|
| 2.9 | 0.024 AU (3.6 million km)[11] | ± 38 million km[11] | 2900 | 1 |
| 5.9 | 0.043 AU (6.4 million km)[12] | ± 31 million km[12] | 1800 | 1 |
| 7.1 | 0.043 AU (6.4 million km)[13] | ± 22 million km[13] | 1500 | 1 |
| 7.9 | 0.066 AU (9.9 million km)[14] | ± 20 million km[14] | 2800 | 1 |
| 8.1 | 0.039 AU (5.8 million km)[15] | ± 12 million km[15] | 1700 | 1 |
| 16.1 | 0.053 AU (7.9 million km)[16] | ± 7 million km[16][b] | 71000 | 0 |
| 16.1 (JPL #12) |
0.059 AU (8.8 million km)[17] | ± 5 million km[17] | 0[3] | 0[3] |
| 20 | 0.072 AU (10.8 million km)[18] | ± 4 million km[18] | 0 | 0 |
| Date & Time | Approach to |
Nominal distance |
|---|---|---|
| 2023-Jul-01 01:13 ± 1 day | Earth | 9246404 km[2] |
| 2023-Jul-01 03:44 | Moon | 9463958 km[19] |
It came to perihelion (closest approach to the Sun) on 10 November 2021, and then approached Earth from the direction of the Sun making closest Earth approach on 31 December 2021 at distance of about 10 million km.[2]
See also
editNotes
edit- ^ a b Earth traveling at 30 km/s and with a diameter of 12,800 km, only blocks the path of the asteroid for about 8 minutes (30 km/s * 60 sec * 8 min).
- ^ a b The JPL Small-Body Database close approach table lists a linearized uncertainty. Sentry computations explore alternate orbit solutions along the line of variations and account for orbit propagation nonlinearities.
- ^ 100.66 = 4.57. JPL's Sentry Risk Table, ESA's Risk List and NEODyS will all list slightly different odds of impact and Palermo Technical Impact Hazard Scale values.
- ^ "Background risk" is defined as the average risk posed by objects of the same size or larger over the years until the date of the potential impact.
References
edit- ^ a b "MPEC 2022-A56 : 2022 AE1". IAU Minor Planet Center. 7 January 2022. Retrieved 10 January 2022. (K22A01E)
- ^ a b c d "JPL Small-Body Database Browser: (2022 AE1)". Jet Propulsion Laboratory. Archived from the original on 1 February 2022. Retrieved 20 January 2022.
- ^ a b c d "Sentry Risk Table: 2022 AE1". NASA JPL CNEOS. Archived from the original on 11 January 2022.
- ^ "2022 AE1 Orbit". Minor Planet Center. Retrieved 20 January 2022.
- ^ "ESA asteroid warning 2023: will "2022 AE1" hit Earth, or not? - Technology Org". www.technology.org. 17 December 2022. Retrieved 18 December 2022.
- ^ a b "ESA Risk List". European Space Agency near-earth objects coordination centre. Archived from the original on 11 January 2022.
- ^ "NEODyS-2 Impactor Table: 2022AE1". NEODyS CLOMON2. Archived from the original on 12 January 2022.
- ^ "JPL Horizons: 2022 AE1 Target-Observer-Moon (lunar elongation) for 13-17 January 2022". JPL Horizons.
- ^ Neo, Operator. "Recap on the removal of 2022 AE1 from the risk list". Near-earth objects coordination centre. European Space Agency Space Safety Programme. Retrieved 23 April 2022.
- ^ "The rise and fall of the riskiest asteroid in a decade". Planetary Defence. European Space Agency. Retrieved 23 April 2022.
- ^ a b "JPL #4 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 2.9 day arc". JPL Horizons. Archived from the original on 10 January 2022.
- ^ a b "JPL #5 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 5.8 day arc". JPL Horizons. Archived from the original on 10 January 2022.
- ^ a b "JPL #6 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 7.1 day arc". JPL Horizons. Archived from the original on 11 January 2022.
- ^ a b "JPL #7 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 7.9 day arc". JPL Horizons. Archived from the original on 12 January 2022.
- ^ a b "JPL #10 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 8.1 day arc". JPL Horizons. Archived from the original on 13 January 2022.
- ^ a b "JPL #11 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 16 day arc". JPL Horizons. Archived from the original on 20 January 2022.
- ^ a b "JPL #13 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 16 day arc". JPL Horizons. Archived from the original on 20 January 2022.
- ^ a b "JPL #15 Horizons Archive: 2022 AE1 geocentric distance and uncertainty with 20 day arc". JPL Horizons. Archived from the original on 24 January 2022.
- ^ "Moon Horizons Batch for 2023-Jul-01". JPL Horizons. Retrieved 20 January 2021.
External links
edit- 2022 AE1 at NeoDyS-2, Near Earth Objects—Dynamic Site
- 2022 AE1 at ESA–space situational awareness
- 2022 AE1 at the JPL Small-Body Database