970 Primula

970 Primula
Discovery [1]
Discovered byK. Reinmuth
Discovery siteHeidelberg Obs.
Discovery date29 November 1921
Designations
(970) Primula
Pronunciation/ˈprɪmjʊlə/[2]
Named after
Primula [3]
(genus of flowers)
A921 WK · 1929 RN
1966 TG · 1921 LB
main-belt [1][4] · (middle)
background [5][6]
Orbital characteristics [4]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc98.11 yr (35,834 d)
Aphelion3.2552 AU
Perihelion1.8644 AU
2.5598 AU
Eccentricity0.2717
4.10 yr (1,496 d)
17.501°
0° 14m 26.52s / day
Inclination5.0331°
310.77°
95.564°
Physical characteristics
9.204±0.289 km[7]
2.777±0.001 h[8][9]
0.229±0.031[7]
SMASS = S [4][6]
12.3[1][4]

970 Primula (prov. designation: A921 WK or 1921 LB) is a stony background asteroid from the central regions of the asteroid belt, approximately 9.2 kilometers (5.7 miles) in diameter. It was discovered on 29 November 1921, by astronomer Karl Reinmuth at the Heidelberg Observatory in southern Germany.[1] The S-type asteroid has a short rotation period of 2.8 hours. It was named after the genus of flowering plants, Primula, which are also known as "primroses".[3]

Orbit and classification

Primula is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.[5][6] It orbits the Sun in the central asteroid belt at a distance of 1.9–3.3 AU once every 4 years and 1 month (1,496 days; semi-major axis of 2.56 AU). Its orbit has an eccentricity of 0.27 and an inclination of 5° with respect to the ecliptic.[4] The body's observation arc begins with its official discovery observation at Heidelberg observatory in November 1921.[1]

Naming

This minor planet was named after the genus of flowering plants, Primula, also known as "primroses". These perennial herbs belong to the family Primulaceae (primrose family) and have large tufted basal leaves and variously colored flowers. The naming was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 93).[3]

Physical characteristics

In the SMASS classification (Bus–Binzel 2000), Primula is a common stony S-type asteroid.[4]

Rotation period

In November 2003, a rotational lightcurve of Primula was obtained from photometric observations by Pedro Sada, Eder Canizales and Edgar Armada using a remotely controlled commercial telescope at Tenagra Observatories (848). Lightcurve analysis gave a well-defined, short rotation period of 2.777±0.001 hours with a brightness variation of 0.18±0.02 magnitude (U=3).[8] Astronomer Maurice Clark at the Preston Gott Observatory confirmed the period in September 2011, measuring 2.7768±0.0001 hours and a somewhat higher amplitude of 0.30±0.02 (U=3)[9]

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Primula measures 9.204±0.289 kilometers in diameter and its surface has an albedo of 0.229±0.031.[7] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a stony asteroid of 0.20 and calculates a diameter of 10.30 kilometers based on an absolute magnitude of 12.3.[10]

References

  1. ^ a b c d e "970 Primula (A921 WK)". Minor Planet Center. Retrieved 10 February 2020.
  2. ^ "primula". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  3. ^ a b c Schmadel, Lutz D. (2007). "(970) Primula". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 85. doi:10.1007/978-3-540-29925-7_971. ISBN 978-3-540-00238-3.
  4. ^ a b c d e f "JPL Small-Body Database Browser: 970 Primula (A921 WK)" (2020-01-08 last obs.). Jet Propulsion Laboratory. Retrieved 10 February 2020.
  5. ^ a b "Asteroid 970 Primula – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 10 February 2020.
  6. ^ a b c "Asteroid 970 Primula". Small Bodies Data Ferret. Retrieved 10 February 2020.
  7. ^ a b c Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 10 February 2020.
  8. ^ a b Sada, Pedro V.; Canizales, Eder D.; Armada, Edgar M. (September 2004). "CCD photometry of asteroids 970 Primula and 1631 Kopff using a remote commercial telescope" (PDF). Minor Planet Bulletin. 31 (3): 49–50. Bibcode:2004MPBu...31...49S. ISSN 1052-8091.
  9. ^ a b Clark, Maurice (April 2012). "Asteroid Lightcurves from the Preston Gott Observatory" (PDF). Minor Planet Bulletin. 39 (2): 63–65. Bibcode:2012MPBu...39...63C. ISSN 1052-8091. Archived from the original (PDF) on 12 February 2020. Retrieved 23 February 2020.
  10. ^ "LCDB Data for (970) Primula". Asteroid Lightcurve Database (LCDB). Retrieved 10 February 2020.