Astronomy:2021 EU
| Discovery[1] | |
|---|---|
| Discovered by | Pan-STARRS |
| Discovery date | 4 March 2021 |
| Designations | |
| 2021 EU | |
| Minor planet category | |
| Orbital characteristics[4] | |
| Epoch 2021-Mar-06 (JD 2459279.5) | |
| Uncertainty parameter 8 | |
| Observation arc | 15 days[2] |
| |{{{apsis}}}|helion}} | 3.58 astronomical unit|AU (Q) |
| |{{{apsis}}}|helion}} | 0.565 AU (q) |
| 2.07 AU (a) | |
| Eccentricity | 0.727 (e) |
| Orbital period | 2.99 years |
| Mean anomaly | 17.2° (M) |
| Inclination | 3.84° (i) |
| Longitude of ascending node | 157.8° (Ω) |
| |{{{apsis}}}|helion}} | 2024-Jan-08?[3] 2021-Jan-12[4] |
| 269° (ω) | |
| Earth MOID | 0.00012 AU (18,000 km) |
| Jupiter MOID | 1.8 AU (270,000,000 km) |
| Physical characteristics | |
| Dimensions |
|
| Absolute magnitude (H) | 25.4[4][5] |
2021 EU is a small near-Earth object that should pass within 0.4 astronomical unit|AU (60 million km) of Earth in 2024.[6] On 27 February 2024 it has a 1-in-32,000 chance of impacting Earth.[2] It is estimated to be 28-meters in diameter which would make it larger than the Chelyabinsk meteor. It has a short observation arc of 15 days and has not been observed since 17 March 2021 when it was 0.23 AU (34 million km) from Earth. On 27 February 2024 it is nominally expected to be 0.09 AU (13 million km) from Earth but has an uncertainty region of ±45 million km (0.30 AU).[6] The nominal 2024 Earth approach would have the asteroid only brightening to apparent magnitude 23 near closest approach.[7]
| Date | Impact probability (1 in) |
JPL Horizons nominal geocentric distance (AU) |
NEODyS nominal geocentric distance (AU) |
MPC[8] nominal geocentric distance (AU) |
Find_Orb nominal geocentric distance (AU) |
uncertainty region (3-sigma) |
|---|---|---|---|---|---|---|
| 2024-02-27 | 32000 | 0.09 astronomical unit|AU (13 million km)[6] | 0.10 AU (15 million km)[7] | 0.10 AU (15 million km) | 0.07 AU (10 million km)[9] | ± 45 million km[6] |
The nominal orbit has it come to perihelion (closest approach to the Sun) on 8 January 2024 and then pass 0.075 AU (11.2 million km) from Earth on 22 February 2024.[3]
References
- ↑ "MPEC 2021-E32 : 2021 EU". IAU Minor Planet Center. 2021-03-05. https://www.minorplanetcenter.net/mpec/K21/K21E32.html. Retrieved 2022-06-11. (K21E00U)
- ↑ 2.0 2.1 2.2 2.3 2.4 "Earth Impact Risk Summary: 2021 EU". NASA/JPL Near-Earth Object Program Office. https://cneos.jpl.nasa.gov/sentry/details.html#?des=2021%20EU. Retrieved 2022-06-11.
- ↑ 3.0 3.1 "Horizons Batch for 2024-02-22 NOMINAL". JPL Horizons. https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272021+EU%27&START_TIME=%272024-01-08%27&STOP_TIME=%272024-02-29%27&STEP_SIZE=%274%20hour%27&QUANTITIES=%2719,20,23%27. Retrieved 2022-06-11.
- ↑ 4.0 4.1 4.2 "JPL Small-Body Database Browser: (2021 EU)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2021EU&view=OPC. Retrieved 2022-06-11.
- ↑ "2021 EU Orbit". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=2021+EU. Retrieved 2022-06-11.
- ↑ 6.0 6.1 6.2 6.3 "Horizons Batch for 2024-02-27 Virtual Impactor". JPL Horizons. https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272021+EU%27&START_TIME=%272024-02-26%27&STOP_TIME=%272024-02-28%27&STEP_SIZE=%271%20day%27&QUANTITIES=%2720,39%27. Retrieved 2022-06-11. RNG_3sigma = uncertainty range in km. (JPL#8/Soln.date: 2022-May-02 generates RNG_3sigma = 44762719 km for 2024-Feb-27.)
- ↑ 7.0 7.1 "2021EU Ephemerides for 27 February 2024". NEODyS (Near Earth Objects – Dynamic Site). https://newton.spacedys.com/neodys/index.php?pc=1.1.3.1&n=2021EU&oc=500&y0=2024&m0=02&d0=26&h0=0&mi0=0&y1=2024&m1=02&d1=28&h1=0&mi1=0&ti=1.0&tiu=days. Retrieved 2022-06-11.
- ↑ "MPC Ephemeris Service". IAU Minor Planet Center. https://minorplanetcenter.net//iau/MPEph/MPEph.html. Retrieved 2022-06-11.
- ↑ "Find_Orb for 2024-02-27". Project Pluto. https://www.projectpluto.com/cgi-bin/fo/fo_serve.cgi?obj_name=2021+EU&year=2024-02-26&n_steps=3&stepsize=1. Retrieved 2022-06-11.
External links
- 2021 EU at NeoDyS-2, Near Earth Objects—Dynamic Site
- Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
- 2021 EU at ESA–space situational awareness
- 2021 EU at the JPL Small-Body Database
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