1055 Tynka

1055 Tynka

Discovery[1]
Discovered by	E. Buchar
Discovery site	Algiers Obs.
Discovery date	17 November 1925
Designations
MPC designation	(1055) Tynka
Named after	Tynka Buchar (discoverer's mother)[2]
Alternative designations	1925 WG · A902 TB
Minor planet category	main-belt · (inner) Flora[3][4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	114.42 yr (41,793 days)
Aphelion	2.6561 AU
Perihelion	1.7402 AU
Semi-major axis	2.1981 AU
Eccentricity	0.2083
Orbital period (sidereal)	3.26 yr (1,190 days)
Mean anomaly	129.33°
Mean motion	0° 18^m 8.64^s / day
Inclination	5.2778°
Longitude of ascending node	147.15°
Argument of perihelion	176.64°
Physical characteristics
Dimensions	8.95±0.22 km[5] 10.31 km (calculated)[3] 13.479±0.225 km[6]
Synodic rotation period	5.9818±0.0003 h[7] 11.75±0.01 h[8] 11.893±0.002 h[9] 11.893±0.005 h[10]
Geometric albedo	0.169±0.023[6] 0.24 (assumed)[3] 0.350±0.019[5]
Spectral type	Tholen = S[1] SMASS = S[1][3]
Absolute magnitude (H)	11.90[6] · 12.00[5] · 12.1[1][3] · 12.33±0.29[11]

1055 Tynka, provisional designation 1925 WG, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 17 November 1925, by Czech astronomer Emil Buchar at the Algiers Observatory in North Africa, who named it after his mother Tynka Buchar.[12]

Orbit and classification

Tynka is a member of the Flora family (402), a giant asteroid family and the largest family of stony asteroids in the main belt.[4][13]: 23  It orbits the Sun in the inner asteroid belt at a distance of 1.7–2.7 AU once every 3 years and 3 months (1,190 days). Its orbit has an eccentricity of 0.21 and an inclination of 5° with respect to the ecliptic.[1]

The body's observation arc begins with its identification as A902 TB at Heidelberg Observatory in October 1902, more than 23 years prior to its official discovery observation at Algiers.[12]

Physical characteristics

Tynka is a common stony S-type asteroid in both the Tholen and SMASS classification,[1] which agrees with the overall spectral type for members of the Flora family.[13]: 23 

Rotation period

Three rotational lightcurves of Tynka were independently obtained from photometric observations by astronomers David Higgins, Agnieszka Kryszczyńska and Robert Stephens. Lightcurve analysis gave a rotation period of 11.75 and 11.893 hours with a brightness variation between 0.06 and 0.33 magnitude (U=2-/2/2).[8][9][10] An alternative period solution of 5.9818 hours with an amplitude of 0.17 was measured by French amateur astronomer René Roy in April 2012 (U=2).[7]

Diameter and albedo

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Tynka measures 8.95 and 13.48 kilometers in diameter and its surface has an albedo of 0.169 and 0.350, respectively.[5][6]

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 10.31 kilometers based on an absolute magnitude of 12.1.[3]

Naming

This minor planet was named by the discoverer after his mother Tynka Buchar. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 100). Emil Buchar (1901–1979) worked at the Institute of Astronomy and Geophysics at the Technical University in Prague and was a pioneer of satellite geodesy.[2] This asteroid was his only minor-planet discovery.[14] The minor planet 3141 Buchar was named in his honor.

References

1. "JPL Small-Body Database Browser: 1055 Tynka (1925 WG)" (2017-03-11 last obs.). Jet Propulsion Laboratory. Retrieved 18 October 2017.
2. Schmadel, Lutz D. (2007). "(1055) Tynka". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 90. doi:10.1007/978-3-540-29925-7_1056. ISBN 978-3-540-00238-3.
3. "LCDB Data for (1055) Tynka". Asteroid Lightcurve Database (LCDB). Retrieved 18 October 2017.
4. "Asteroid 1055 Tynka". Small Bodies Data Ferret – Nesvorny HCM Asteroid Families V3.0. Retrieved 26 October 2019.
5. 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)
6. 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.
7. Behrend, Raoul. "Asteroids and comets rotation curves – (1055) Tynka". Geneva Observatory. Retrieved 18 October 2017.
8. Stephens, Robert D. (October 2012). "Asteroids Observed from Santana, CS3 and GMARS Observatories: 2012 April - June". The Minor Planet Bulletin. 39 (4): 226–228. Bibcode:2012MPBu...39..226S. ISSN 1052-8091.
9. Higgins, David; Pilcher, Frederick (October 2009). "Lightcurve Analysis of 48 Doris and 1055 Tynka". The Minor Planet Bulletin. 36 (4): 143–144. Bibcode:2009MPBu...36..143H. ISSN 1052-8091.
10. 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" (PDF). Astronomy and Astrophysics. 546: 51. Bibcode:2012A&A...546A..72K. doi:10.1051/0004-6361/201219199.
11. 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:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007.
12. "1055 Tynka (1925 WG)". Minor Planet Center. Retrieved 18 October 2017.
13. Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families". Asteroids IV. pp. 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. ISBN 9780816532131.
14. "Minor Planet Discoverers (by number)". Minor Planet Center. 3 October 2017. Retrieved 18 October 2017.

External links

• Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
• Dictionary of Minor Planet Names, Google books
• Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
• Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
• 1055 Tynka at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
• 1055 Tynka at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters