(341843) 2008 EV5

Source: Wikipedia, the free encyclopedia.

(341843) 2008 EV5
Synodic rotation period
3.717±0.008 h[7]
3.725 h[8]
3.7255±0.002 h[9]
7.2 h[10]
10.200±0.002 h[8]
0.104±0.312[6]
0.12±0.04[3]
0.13±0.05[4]
0.137±0.013[6]
0.1373±0.0129[5]
X[11] · C[12] · S (assumed)[8]
19.7[5][6] · 19.91[8] · 20.0[2] · 20.0±0.4[4]

(341843) 2008 EV5, provisional designation 2008 EV5, is a sub-kilometer

potentially hazardous asteroid of the Aten group, approximately 400 metres (1,300 feet) in diameter. It was discovered on 4 March 2008, by astronomers of the Mount Lemmon Survey at Mount Lemmon Observatory near Tucson, Arizona, United States.[1]

Origin and orbital history

2008 EV5 started its existence as part of a much larger body in the asteroid belt, with a likely diameter greater than 100 kilometers.[13] 2008 EV5's immediate history likely started when its parent body experienced a large cratering event or, more likely, a catastrophic disruption event that resulted in a highly fractured, shattered, or reaccumulated object (rubble pile). As a result, 2008 EV5 may have been produced as a reassembly of ejected fragments. The location of what is now 2008 EV5 within this parent body is unknown.[14]

Given the available modeling work and data, the most plausible source family candidates for 2008 EV5 are

C-type asteroids in the inner asteroid belt. Second tier candidate families for the high-albedo case are Baptistina and Pallas.[14]

From here, the newly liberated 2008 EV5 began to change via the forces referred to as the

YORP effects. The Yarkovsky effect describes a small force that affects orbital motion. It is caused by sunlight; when objects heat up in the Sun, they reradiate the energy away as heat, which in turn creates a tiny thrust. This recoil acceleration is much weaker than solar and planetary gravitational forces, but it can produce substantial orbital changes over timescales ranging from many millions to billions of years. The same physical phenomenon also creates a thermal torque that probably caused 2008 EV5 to take on a top-like appearance.[3][14][15]

Dynamical models indicate that 2008 EV5 migrated inward across the inner asteroid belt over long timescales (i.e. the order of ~0.01–1 Gyr) until it reached a planetary gravitational resonance that drove it into the near-Earth asteroid (NEA) population over a timescale of the order of ~1 Myr. From there, gravitational interactions with both the planets and resonances allowed it to reach its current orbit within a few Myr to a few tens of Myr.[14]

Close approaches

On 23 December 2008, 2008 EV5 made a close approach to Earth at a distance of 8.4 lunar distances (0.022 AU, 3.2 million km), its closest until 2169.[3] Its brightness peaked on 26 December about 13.2 magnitude.

2008 Path of 2008 EV5 close approach, with 3 day motion markers
Earth Approach on 20 December 2023[2]
Date
JPL Horizons
nominal geocentric
distance (AU
) 		uncertainty
region
(
3-sigma
)
2023-Dec-20 06:52 0.04226 AU (6.322 million km)[2] ±1741 km[16]

Physical characteristics

Radar-based shape model of 2008 EV5

2008 EV5 is an

oblate spheroid (also described as "muffin-shaped"[17]
) 400 m (1,300 ft) in diameter. It rotates very slowly in a retrograde direction. There is a 150 m (490 ft) diameter concave feature, possibly an impact crater, or a relic feature from a previous episode of rapid rotation that caused the asteroid's shape to reconfigure.[3]

Visible and near-infrared spectroscopy show that 2008 EV5's composition is similar to that of carbonaceous chondrite meteorites.[12]

Proposed sample return mission

2008 EV5 was the preliminary baseline target of

sample-return Asteroid Redirect Mission. Besides 2008 EV5, several other asteroids, including Itokawa and Bennu, were considered for this mission,[18][19]
before its cancellation in 2017.

See also

References

  1. ^ a b c "341843 (2008 EV5)". Minor Planet Center. Retrieved 17 January 2018.
  2. ^ a b c d e "JPL Small-Body Database Browser: 341843 (2008 EV5)" (2010-04-11 last obs.). Jet Propulsion Laboratory. Retrieved 17 January 2018.
  3. ^
    S2CID 56469588
    . Retrieved 17 January 2018.
  4. ^
    S2CID 119268126
    .
  5. ^
    S2CID 118700974
    .
  6. ^
    S2CID 239991
    .
  7. ISSN 1052-8091
    .
  8. ^ a b c d "LCDB Data for (341843)". Asteroid Lightcurve Database (LCDB). Retrieved 17 January 2018.
  9. ISSN 1052-8091
    .
  10. ^ Behrend, Raoul. "Asteroids and comets rotation curves – (341843)". Geneva Observatory. Retrieved 17 January 2018.
  11. S2CID 119307210
    .
  12. ^
    S2CID 119243535
    .
  13. S2CID 12632943
    .
  14. ^
    National Aeronautics and Space Administration. Retrieved 20 February 2016. Public Domain This article incorporates text from this source, which is in the public domain
    .
  15. S2CID 4418744
    .
  16. ^ "Horizons Batch for 2023-12-20 Close Approach". JPL Horizons. Archived from the original on 26 October 2022. Retrieved 26 October 2022. RNG_3sigma = uncertainty range in km. (JPL#107/Soln.date: 2021-Apr-14 generates RNG_3sigma = 1741 km)
  17. AP News
    . Retrieved 24 December 2018.
  18. ^ Steitz, David E. (25 March 2015). "RELEASE 15-050 - NASA Announces Next Steps on Journey to Mars: Progress on Asteroid Initiative". NASA. Retrieved 26 March 2015.
  19. AP News
    . Retrieved 26 March 2015.

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=(341843)_2008_EV5&oldid=1195659045"