982 Franklina

982 Franklina
Modelled shape of Franklina from its lightcurve
Discovery [1]
Discovered byH. E. Wood
Discovery siteJohannesburg Obs.
Discovery date21 May 1922
Designations
(982) Franklina
Named after
John Franklin Adams
(British astronomer)[2]
A922 KF · 1922 MD
1928 QF · 1938 HG
main-belt [1][3] · (outer)
background [4][5]
Orbital characteristics [3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc91.15 yr (33,291 d)
Aphelion3.7852 AU
Perihelion2.3472 AU
3.0662 AU
Eccentricity0.2345
5.37 yr (1,961 d)
35.422°
0° 11m 0.96s / day
Inclination13.657°
299.15°
350.82°
Physical characteristics
  • 31.07±0.86 km[6]
  • 32.47±3.0 km[7]
  • 33.227±4.627 km[8]
>16 h[9][a]
  • 0.1838±0.040[7]
  • 0.184±0.396[8]
  • 0.214±0.013[6]

982 Franklina (prov. designation: A922 KF or 1922 MD) is a background asteroid from the outer regions of the asteroid belt, approximately 32 kilometers (20 miles) in diameter. It was discovered on 21 May 1922, by South African astronomer Harry Edwin Wood at the Union Observatory in Johannesburg.[1] The uncommon A/Ld-type asteroid has a rotation period of at least 16 hours.[5] It was named after British amateur astronomer John Franklin Adams (1843–1912).[2]

Orbit and classification

Franklina is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.[4][5] It orbits the Sun in the outer asteroid belt at a distance of 2.3–3.8 AU once every 5 years and 4 months (1,961 days; semi-major axis of 3.07 AU). Its orbit has an eccentricity of 0.23 and an inclination of 14° with respect to the ecliptic.[3] The body's first observation was its discovery observation at Johannesburg on 21 May 1922. Its observation arc begins with it first used observation at Simeiz Observatory on 18 August 1928, more than 6 years after to its official discovery observation.[1]

Naming

This minor planet was named after British amateur astronomer and stellar cartographer John Franklin Adams (1843–1912), who created one of the earliest detailed, photographic atlases of the complete night sky (the Franklin-Adams plates or charts). He later donated his 25-centimeter Franklin-Adams Star Camera (Franklin-Adams photographic refractor) to the Johannesburg Observatory, which lead to the discovery of Proxima Centauri.[2][11][12] The naming was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 94).[2] Another asteroid, 1925 Franklin-Adams, discovered by Hendrik van Gent in 1934, was also named in his memory on 20 December 1983 (M.P.C. 8402).[11]

Physical characteristics

In the Tholen- and SMASS-like taxonomy of the Small Solar System Objects Spectroscopic Survey (S3OS2), Franklina is an uncommon A-type and Ld-type asteroid, respectively.[5][10]

Rotation period

In October 2004, a rotational lightcurve of Franklina was obtained from photometric observations by American Brian Warner at his Palmer Divide Observatory (716) in Colorado . Lightcurve analysis gave a rotation period of at least 16 hours with a brightness amplitude of 0.05 magnitude or more (U=2−). The results, however, apart from an 8-hour long decline in brightness, are not very conclusive.[9][a] Two month earlier, French amateur astronomer Cyril Cavadore also attempted to determine the asteroid's period with little success (U=1).[13] Based on its exceptionally low brightness variation, Franklina might be a rather spherical body with little to no albedo features on its surface, or, it might be due to a yet undetermined long period. Typically, a collaboration of astronomers taking photometric measurements around the globe is required to measures the period of such slow rotators.

Diameter and albedo

According to the survey carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Franklina measures between 31.1 and 33.2 kilometers in diameter and its surface has an albedo between 0.18 and 0.21.[6][7][8] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.1837, and adopts a diameter of 32.47 kilometers from IRAS, based on an absolute magnitude of 9.9.[14]

Notes

  1. ^ a b Lightcurve plot of (982) Franklina, Palmer Divide Observatory, by B. D. Warner (2004). Rotation period of at least 16 hours with a brightness amplitude of >0.05 mag. Quality code is 2−. Summary figures at the LCDB.

References

  1. ^ a b c d e "982 Franklina (A922 KF)". Minor Planet Center. Retrieved 8 February 2020.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(982) Franklina". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 85. doi:10.1007/978-3-540-29925-7_983. ISBN 978-3-540-00238-3.
  3. ^ a b c d "JPL Small-Body Database Browser: 982 Franklina (A922 KF)" (2019-10-09 last obs.). Jet Propulsion Laboratory. Retrieved 8 February 2020.
  4. ^ a b "Asteroid 982 Franklina – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 8 February 2020.
  5. ^ a b c d "Asteroid 982 Franklina". Small Bodies Data Ferret. Retrieved 8 February 2020.
  6. ^ a b c Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
  7. ^ a b c Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 8 February 2020.
  8. ^ a b c Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8.
  9. ^ a b Warner, Brian D. (April 2011). "Asteroid Lightcurve Analysis at the Palmer Divide Observatory: Unpublished Results from 1999 to 2008". The Minor Planet Bulletin. 38 (2): 89–92. Bibcode:2011MPBu...38...89W. Retrieved 8 February 2020.
  10. ^ a b c Lazzaro, D.; Angeli, C. A.; Carvano, J. M.; Mothé-Diniz, T.; Duffard, R.; Florczak, M. (November 2004). "S3OS2: the visible spectroscopic survey of 820 asteroids" (PDF). Icarus. 172 (1): 179–220. Bibcode:2004Icar..172..179L. doi:10.1016/j.icarus.2004.06.006. Retrieved 8 February 2020.
  11. ^ a b Schmadel, Lutz D. (2007). "(1925) Franklin-Adams". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 155. doi:10.1007/978-3-540-29925-7_1926. ISBN 978-3-540-00238-3.
  12. ^ "The Internet Encyclopedia of Science". David Darling. Archived from the original on 22 March 2017.
  13. ^ Behrend, Raoul. "Asteroids and comets rotation curves – (982) Franklina". Geneva Observatory. Retrieved 8 February 2020.
  14. ^ "LCDB Data for (982) Franklina". Asteroid Lightcurve Database (LCDB). Retrieved 8 February 2020.