919 Ilsebill

Summary

919 Ilsebill (prov. designation: A918 UD or 1918 EQ) is a dark background asteroid from the central region of the asteroid belt. It was discovered on 30 October 1918, by astronomer Max Wolf at the Heidelberg-Königstuhl State Observatory in southwest Germany.[1] The carbonaceous C-type asteroid has a short rotation period of 5.0 hours and measures approximately 33 kilometers (21 miles) in diameter. It was named after "Ilsebill", a character in the fairy tale The Fisherman and his Wife by the Brothers Grimm.[2]

919 Ilsebill
Discovery [1]
Discovered byM. F. Wolf
Discovery siteHeidelberg Obs.
Discovery date30 October 1918
Designations
(919) Ilsebill
Named after
Fairy tale character "Ilsebill"
(The Fisherman and his Wife)[2]
A918 UD · 1935 JG
1950 RP · 1950 SE
1950 TN · 1972 MA
1918 EQ
main-belt[1][3] · (middle)
background[4][5]
Orbital characteristics[3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc101.19 yr (36,960 d)
Aphelion3.0033 AU
Perihelion2.5408 AU
2.7721 AU
Eccentricity0.0834
4.62 yr (1,686 d)
14.861°
0° 12m 48.96s / day
Inclination8.1657°
229.83°
156.02°
Physical characteristics
Mean diameter
  • 27.65±1.7 km[6]
  • 33.41±0.49 km[7]
  • 33.500±0.071 km[8]
5.0325±0.0011 h[9]
  • 0.047±0.010[8]
  • 0.048±0.002[7]
  • 0.0698±0.010[6]
11.4[1][3]

Orbit and classification edit

Ilsebill 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 central asteroid belt at a distance of 2.5–3.0 AU once every 4 years and 7 months (1,686 days; semi-major axis of 2.77 AU). Its orbit has an eccentricity of 0.08 and an inclination of 8° with respect to the ecliptic.[3] The body's observation arc begins at Heidelberg Observatory with its official discovery observation on 30 October 1918.[1]

Naming edit

This minor planet was named after the character "Ilsebill" in the fairy tale The Fisherman and his Wife (German: Von dem Fischer und seiner Frau) by the Brothers Grimm. The asteroid was named likely after the discoverer's death in 1932, upon a proposal made by his widow Gisela Wolf, and subsequently published by ARI (RI 1013). The naming was also mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 89).[2]

Physical characteristics edit

In the Bus–Binzel SMASS classification and in the SDSS-based taxonomy, Ilsebill is a common, carbonaceous C-type asteroid.[3][5][10]

Rotation period edit

In October 2010, a rotational lightcurve of Ilsebill was obtained from photometric observations by Zachary Pligge, Ben Hall and Richard Ditteon at the U.S. Oakley Observatory (916) in Indiana. Lightcurve analysis gave a well-defined rotation period of 5.0325±0.0011 hours with a brightness variation of 0.25±0.02 magnitude (U=3).[9] In September 2010, a similar, though lower rated period of 5.034±0.0010 hours with an amplitude of 0.24 was determined by astronomers at the Palomar Transient Factory in California (U=2).[11][12]

A modeled lightcurve using photometric data from the Lowell Photometric Database and from the Wide-field Infrared Survey Explorer (WISE) was published in 2018. It gave a concurring sidereal period of 5.03348±0.00002 hours and includes a partial spin axis at (β1 = −53.0°) in ecliptic coordinates (λ, β).[13]

Diameter and albedo edit

According to the survey carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and the NEOWISE mission of NASA's WISE telescope, Ilsebill measures (27.65±1.7), (33.41±0.49) and (33.500±0.071) kilometers in diameter and its surface has a low albedo of (0.0698±0.010), (0.048±0.002) and (0.047±0.010), respectively.[6][7][8] The Collaborative Asteroid Lightcurve Link derives its estimate from IRAS, that is, an albedo of 0.0638 and a diameter of 27.62 km based on an absolute magnitude of 11.4.[11] Further published mean-diameters by the WISE team include (29.37±9.40 km), (32.598±7.912 km), (33.17±0.16 km), (34.444±0.254 km) and (38.64±12.97 km) with albedos between (0.027±0.046) and (0.05±0.03).[5][11]

References edit

  1. ^ a b c d e "919 Ilsebill (A918 UD)". Minor Planet Center. Retrieved 22 February 2020.
  2. ^ a b c Schmadel, Lutz D. (2007). "(919) Ilsebill". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 82. doi:10.1007/978-3-540-29925-7_920. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f "JPL Small-Body Database Browser: 919 Ilsebill (A918 UD)" (2020-01-08 last obs.). Jet Propulsion Laboratory. Retrieved 22 February 2020.
  4. ^ a b "Asteroid 919 Ilsebill – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 22 February 2020.
  5. ^ a b c d "Asteroid 919 Ilsebill". Small Bodies Data Ferret. Retrieved 22 February 2020.
  6. ^ 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 22 February 2020.
  7. ^ 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)
  8. ^ a b c 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:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. S2CID 119293330.
  9. ^ a b Pligge, Zachary; Hall, Ben; Ditteon, Richard (July 2011). "Asteroid Lightcurve Analysis at the Oakley Observatory: 2010 September thru October" (PDF). Minor Planet Bulletin. 38 (3): 137–138. Bibcode:2011MPBu...38..137P. ISSN 1052-8091.
  10. ^ a b Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids". Astronomy and Astrophysics. 510: 12. Bibcode:2010A&A...510A..43C. doi:10.1051/0004-6361/200913322. Retrieved 22 February 2020. (PDS data set)
  11. ^ a b c "LCDB Data for (919) Ilsebill". Asteroid Lightcurve Database (LCDB). Retrieved 22 February 2020.
  12. ^ Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). "Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry". The Astronomical Journal. 150 (3): 75. arXiv:1504.04041. Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75. ISSN 0004-6256. S2CID 8342929.
  13. ^ Ďurech, J.; Hanuš, J.; Alí-Lagoa, V. (September 2018). "Asteroid models reconstructed from the Lowell Photometric Database and WISE data". Astronomy and Astrophysics. 617: A57. arXiv:1807.02083. Bibcode:2018A&A...617A..57D. doi:10.1051/0004-6361/201833437. ISSN 0004-6361. S2CID 119388288.

External links edit

  • Lightcurve Database Query (LCDB), at www.minorplanet.info
  • Dictionary of Minor Planet Names, Google books
  • Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
  • 919 Ilsebill at AstDyS-2, Asteroids—Dynamic Site
    • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
  • 919 Ilsebill at the JPL Small-Body Database  
    • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters