2195 Tengström
Stony Florian asteroid from the inner regions of the asteroid belt
2195 Tengström , provisional designation 1941 SP1 , is a stony Florian asteroid from the inner regions of the asteroid belt , approximately 8 kilometers in diameter. It was discovered on 27 September 1941, by Finnish astronomer Liisi Oterma at Turku Observatory in Southwest Finland,[ 12] and named for Swedish geodesist Erik Tengström .[ 2]
Orbit and classification
Tengström is a member of the Flora family of stony asteroids, one of the largest families of the main belt. It orbits the Sun in the inner main-belt at a distance of 2.0–2.5 AU once every 3 years and 4 months (1,210 days). Its orbit has an eccentricity of 0.11 and an inclination of 5° with respect to the ecliptic .[ 1] It was first identified as 1931 TC3 at Lowell Observatory in 1931, extending the asteroid's observation arc by 10 years prior to its official discovery observation at Turku.[ 12]
Physical characteristics
Tengström has been characterized as a metallic M-type and stony S-type asteroid .[ 3] [ 7]
Rotation period
Between 2006 and 2016, several well defined rotational lightcurves of Tengström were obtained by astronomers David Higgins , Petr Pravec , Pierre Antonini and René Roy (U=3/3/3/3/3 ).[ 9] [ a] [ b] [ c] Lightcurve analysis gave a rotation period of 2.821 hours with a brightness variation between 0.17 and 0.45 magnitude .[ d] For an asteroid of its size, Tengström has a relatively fast spin rate, not far from the 2.2-hour threshold for fast rotators .
Diameter and albedo
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Tengström measures between 7.14 and 8.73 kilometers in diameter and its surface has a high albedo of 0.34 to 0.45. NEOWISE also classifies it as a metallic asteroid, despite its much higher albedo.[ 4] [ 5] [ 6] [ 7] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – derived from 8 Flora , the family's largest member and namesake – and calculates a diameter of 8.98 kilometers using an absolute magnitude of 12.4.[ 3]
Naming
This minor planet was named after Swedish geodesist and astronomer Erik Tengström (1913–1996), emeritus professor at Uppsala University on the celebration of his 70th anniversary.[ 2] The official naming citation was published by the Minor Planet Center on 28 March 1983 (M.P.C. 7782 ).[ 13]
Notes
^ a b Pravec (2011) web: rotation period 2.82092 ± 0.00004 hours; amplitude of 0.31 mag.; quality code of 3. Summary figures for (2195) Tengström at Collaborative Asteroid Lightcurve Link (CALL) and Pravec, P.; Wolf, M.; Sarounova, L. (2011)
^ a b Pravec (2016) web: rotation period 2.8210± 0.0001 hours; amplitude of 0.21 mag.; quality code of 3. Summary figures for (2195) Tengström at Collaborative Asteroid Lightcurve Link (CALL) and Pravec, P.; Wolf, M.; Sarounova, L. (2016)
^ a b Higgins (2011) web: rotation period 2.82112 ± 0.00007 hours; amplitude of 0.17 mag.; quality code of 3. Summary figures for (2195) Tengström at Collaborative Asteroid Lightcurve Link (CALL)
^ Lightcurve plot from December 2011, 2.82092 hours and April 2016, 2.8210 hours by Pray, Kusnirak, Pravec Ondřejov Observatory – unpublished data
References
^ a b c d "JPL Small-Body Database Browser: 2195 Tengstrom (1941 SP1)" (2017-05-04 last obs.). Jet Propulsion Laboratory . Retrieved 11 June 2017 .
^ a b c Schmadel, Lutz D. (2007). "(2195) Tengström". Dictionary of Minor Planet Names – (2195) Tengström . Springer Berlin Heidelberg . p. 178. doi :10.1007/978-3-540-29925-7_2196 . ISBN 978-3-540-00238-3 .
^ a b c d e f g "LCDB Data for (2195) Tengström" . Asteroid Lightcurve Database (LCDB). Retrieved 17 February 2017 .
^ a b c d Nugent, C. R.; Mainzer, A.; Masiero, J.; Bauer, J.; Cutri, R. M.; Grav, T.; et al. (December 2015). "NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos" . The Astrophysical Journal . 814 (2): 13. arXiv :1509.02522 . Bibcode :2015ApJ...814..117N . doi :10.1088/0004-637X/814/2/117 . Retrieved 17 February 2017 .
^ 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 :1209.5794 . Bibcode :2012ApJ...759L...8M . doi :10.1088/2041-8205/759/1/L8 . Retrieved 17 February 2017 .
^ 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 17 February 2017 .
^ a b c d e f Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal . 741 (2): 25. arXiv :1109.6407 . Bibcode :2011ApJ...741...90M . doi :10.1088/0004-637X/741/2/90 .
^ Higgins, David; Pravec, Petr; Kusnirak, Peter; Galad, Adrian; Kornos, Leos; Pray, Donald; et al. (December 2006). "Asteriod [sic] lightcurve analysis at Hunters Hill Observatory and collaborating stations - autumn 2006" . The Minor Planet Bulletin . 33 (4): 89– 91. Bibcode :2006MPBu...33...89H . ISSN 1052-8091 . Retrieved 17 February 2017 .
^ a b c d Behrend, Raoul. "Asteroids and comets rotation curves – (2195) Tengström" . Geneva Observatory . Retrieved 17 February 2017 .
^ a b 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): 35. arXiv :1504.04041 . Bibcode :2015AJ....150...75W . doi :10.1088/0004-6256/150/3/75 . Retrieved 17 February 2017 .
^ 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 . Retrieved 17 February 2017 .
^ a b "2195 Tengstrom (1941 SP1)" . Minor Planet Center . Retrieved 17 February 2017 .
^ "MPC/MPO/MPS Archive" . Minor Planet Center . Retrieved 17 February 2017 .
External links