2608 Seneca

2608 Seneca
Discovery [1]
Discovered byH.-E. Schuster
Discovery siteLa Silla Obs.
Discovery date17 February 1978
Designations
(2608) Seneca
Pronunciation/ˈsɛnɪkə/ SEN-ik-ə[2]
Named after
Seneca the Younger
(Roman philosopher)[3]
1978 DA
NEO · Amor [1][4]
Orbital characteristics [1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 1
Observation arc38.92 yr (14,217 days)
Aphelion3.9532 AU
Perihelion1.0777 AU
2.5154 AU
Eccentricity0.5716
3.99 yr (1,457 days)
353.12°
0° 14m 49.56s / day
Inclination14.682°
167.37°
37.350°
Earth MOID0.1321 AU · 51.5 LD
Physical characteristics
Dimensions0.9 km[1][5][6]
1.0±0.3[6]
8 h[6]
0.15±0.03[6]
0.20 (derived)[5]
0.21[1]
Tholen = S [1] · S [5]
B–V = 0.826[1]
U–B = 0.454[1]
17.52[1] · 17.59[5][7] · 17.73[6]

2608 Seneca, provisional designation 1978 DA, is a stony asteroid and sub-kilometer near-Earth object of the Amor group, approximately 0.9 kilometers in diameter. It was discovered on 17 February 1978, by German astronomer Hans-Emil Schuster at ESO's La Silla Observatory in northern Chile, and named after Roman philosopher Seneca.[3][4]

Orbit

Seneca orbits the Sun at a distance of 1.1–4.0 AU once every 3 years and 12 months (1,457 days). Its orbit has an eccentricity of 0.57 and an inclination of 15° with respect to the ecliptic.[1]

The body's observation arc begins with its official discovery observation in 1978, as no precoveries were taken, and no prior identifications were made.[4]

Close approaches

Seneca has an Earth minimum orbital intersection distance of 0.1321 AU (19,800,000 km), which corresponds to 51.5 lunar distances.[1] On 22 March 2062, it will pass 0.254 AU (38,000,000 km) from the Earth.[8]

Physical characteristics

In the Tholen taxonomy, Seneca is a stony S-type asteroid.[1]

Photometry

In March 1978, a photometric observations taken by Degewij and Lebofsky at the Lunar and Planetary Laboratory, Arizona, using a 154-cm reflector, gave a rotational lightcurve with a rotation period of 8 hours and a brightness amplitude of 0.4 (0.5) magnitude (U=2).[6]

Radiometry

In addition, radiometric observations by L. and M. Lebofsky with the 71-cm reflector gave a mean-diameter of 1.0±0.3 kilometers and albedo of 0.15±0.03.[6]

Diameter and albedo

The Minor Planet Center classifies Seneca as an object larger than 1 kilometer ("1+ KM Near-Earth Object"),[4] while Collaborative Asteroid Lightcurve Link derives an albedo of 0.20 and a diameter of 0.9 kilometers based on an absolute magnitude of 17.59.[5] In 1994, astronomer Tom Gehrels published a diameter of 0.9 kilometers with an albedo of 0.21 in his Hazards Due to Comets and Asteroids.[1]

Naming

This minor planet was named after Roman philosopher and statesman Lucius Annaeus Seneca (c. 4 BC – AD 65), also known as "Seneca the Younger" or simply "Seneca".[3] The approved naming citation was published by the Minor Planet Center on 8 April 1982 (M.P.C. 6835).[9] The lunar crater Seneca was also named in his honor.[3]

References

  1. ^ a b c d e f g h i j k l m "JPL Small-Body Database Browser: 2608 Seneca (1978 DA)" (2017-01-20 last obs.). Jet Propulsion Laboratory. Retrieved 3 July 2017.
  2. ^ "Seneca". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  3. ^ a b c d Schmadel, Lutz D. (2007). "(2608) Seneca". Dictionary of Minor Planet Names – (2608) Seneca. Springer Berlin Heidelberg. p. 213. doi:10.1007/978-3-540-29925-7_2609. ISBN 978-3-540-00238-3.
  4. ^ a b c d "2608 Seneca (1978 DA)". Minor Planet Center. Retrieved 26 March 2017.
  5. ^ a b c d e "LCDB Data for (2608) Seneca". Asteroid Lightcurve Database (LCDB). Retrieved 26 March 2017.
  6. ^ a b c d e f g Degewij, J.; Lebofsky, L.; Lebofsky, M. (March 1978). "1978 CA and 1978 DA". IAU Circ. 3193 (3193): 1. Bibcode:1978IAUC.3193....1D. Retrieved 26 March 2017.
  7. ^ Schuster, H. E.; Surdej, A.; Surdej, J. (September 1979). "Photoelectric observations of two unusual asteroids - 1978 CA and 1978 DA". Astronomy and Astrophysics Supplement Series. 37: 483–486. Bibcode:1979A&AS...37..483S. Retrieved 26 March 2017.
  8. ^ "JPL Close-Approach Data: 2608 Seneca (1978 DA)" (2010-08-19 last obs). Retrieved 15 April 2016.
  9. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 26 March 2017.