1056 Azalea

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
1056 Azalea
1056Azalea (Lightcurve Inversion).png
Light curve-based 3D-model of 1056 Azalea
Discovery [1]
Discovered by K. Reinmuth
Discovery site Heidelberg Obs.
Discovery date 31 January 1924
MPC designation (1056) Azalea
Named after
Azalea (flower)[2]
1924 QD · 1925 NA
1929 WX
main-belt · (inner)
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 93.24 yr (34,057 days)
Aphelion 2.6277 AU
Perihelion 1.8321 AU
2.2299 AU
Eccentricity 0.1784
3.33 yr (1,216 days)
0° 17m 45.6s / day
Inclination 5.4267°
Physical characteristics
Dimensions 10.66±1.99 km[5]
11.76±0.54 km[6]
11.869±0.136 km[7]
12.40 km (calculated)[3]
12.984±0.069 km[8]
13.07±0.64 km[9]
15.0276 h[10]
15.03±0.05 h[11]
15.15±0.03 h[12]
0.24 (assumed)[3]
SMASS = S[1] · S[3]
11.60[6][8] · 11.70[1][3][9] · 11.73±0.28[13] · 11.83[5]

1056 Azalea, provisional designation 1924 QD, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 12 kilometers in diameter. It was discovered on 31 January 1924, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany.[14] The asteroid is named after the Azalea flower.[2]

Orbit and classification[edit]

Azalea is a member of the Flora family (402), a giant asteroid family and the largest family of stony asteroids in the main belt.[3][4][15]:23 It orbits the Sun in the inner main belt at a distance of 1.8–2.6 AU once every 3 years and 4 months (1,216 days). Its orbit has an eccentricity of 0.18 and an inclination of 5° with respect to the ecliptic.[1] The body's observation arc begins at Heidelberg in April 1928, more than 4 years after its official discovery observation.[14]

Physical characteristics[edit]

In the SMASS classification, Azalea is a common stony S-type asteroid.[1]

Rotation period[edit]

In 2004, two rotational lightcurves of Azalea were obtained from photometric observations by a group of predominately Polish astronomers including Agnieszka Kryszczyńska, as well as by astronomers Alain Klotz and Raoul Behrend. Lightcurve analysis gave a rotation period of 15.03 and 15.15 hours with a high brightness variation of 0.70 and 0.79 magnitude, respectively (U=2/2).[11][12] The high brightness amplitude is typically indicative for a non-spheroidal shape.

Spin axis[edit]

In 2013, an international study modeled a lightcurve with a concurring period of 15.0276 hours and found two spin axis of (252.0°, 51.0°) and (64.0°, 41.0°) in ecliptic coordinates (λ, β) (U=n.a.).[10]

Diameter and albedo[edit]

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Azalea measures between 10.66 and 13.07 kilometers in diameter and its surface has an albedo between 0.223 and 0.34.[5][6][7][8][9]

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – derived from 8 Flora, the largest member and namesake of the Flora family – and calculates a diameter of 12.40 kilometers based on an absolute magnitude of 11.7.[3]


This minor planet was named after the genus of flowering shrubs, Azalea, which are rhododendrons with funnel-shaped corollas.[2] The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 100).[2]


  1. ^ a b c d e f "JPL Small-Body Database Browser: 1056 Azalea (1924 QD)" (2017-04-30 last obs.). Jet Propulsion Laboratory. Retrieved 30 August 2017. 
  2. ^ a b c d Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1056) Azalea. Springer Berlin Heidelberg. p. 90. ISBN 978-3-540-00238-3. Retrieved 30 August 2017. 
  3. ^ a b c d e f g "LCDB Data for (1056) Azalea". Asteroid Lightcurve Database (LCDB). Retrieved 30 August 2017. 
  4. ^ a b "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Archived from the original on 16 August 2017. Retrieved 30 August 2017. 
  5. ^ a b c d Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal. 152 (3): 12. arXiv:1606.08923Freely accessible. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63. Retrieved 30 August 2017. 
  6. ^ a b c d 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:1209.5794Freely accessible. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8. Retrieved 30 August 2017. 
  7. ^ a b Masiero, Joseph R.; Grav, T.; Mainzer, A. K.; Nugent, C. R.; Bauer, J. M.; Stevenson, R.; et al. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal. 791 (2): 11. arXiv:1406.6645Freely accessible. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. Retrieved 30 August 2017. 
  8. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results" (PDF). The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407Freely accessible. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 30 August 2017. 
  9. ^ a b c d 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. Retrieved 30 August 2017. 
  10. ^ a b Hanus, J.; Broz, M.; Durech, J.; Warner, B. D.; Brinsfield, J.; Durkee, R.; et al. (November 2013). "An anisotropic distribution of spin vectors in asteroid families". Astronomy and Astrophysics. 559: 19. arXiv:1309.4296Freely accessible. Bibcode:2013A&A...559A.134H. doi:10.1051/0004-6361/201321993. Retrieved 30 August 2017. 
  11. ^ a b Kryszczynska, A.; Colas, F.; Polinska, M.; Hirsch, R.; Ivanova, V.; Apostolovska, G.; et al. (October 2012). "Do Slivan states exist in the Flora family?. I. Photometric survey of the Flora region". Astronomy and Astrophysics. 546: 51. Bibcode:2012A&A...546A..72K. doi:10.1051/0004-6361/201219199. Retrieved 30 August 2017. 
  12. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1056) Azalea". Geneva Observatory. Retrieved 30 August 2017. 
  13. ^ Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762Freely accessible. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 30 August 2017. 
  14. ^ a b "1056 Azalea (1924 QD)". Minor Planet Center. Retrieved 30 August 2017. 
  15. ^ Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families" (PDF). Asteroids IV: 297–321. arXiv:1502.01628Freely accessible. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. Retrieved 30 August 2017. 

External links[edit]