1719 Jens, provisional designation 1950 DP, is an asteroid from the central region of the asteroid belt, approximately 19 kilometers in diameter. It was discovered on 17 February 1950, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany.[13] It was named after a grandson of the discoverer.[2]

1719 Jens
Discovery [1]
Discovered byK. Reinmuth
Discovery siteHeidelberg Obs.
Discovery date17 February 1950
MPC designation(1719) Jens
Named after
Jens (discoverer's grandson)[2]
1950 DP · 1939 PP
1939 TD · 1941 BB
1948 RQ · 1948 RS1
1948 TS1 · 1961 TZ1
A922 SC
main-belt · (middle)[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc68.65 yr (25,074 days)
Aphelion3.2474 AU
Perihelion2.0649 AU
2.6562 AU
4.33 yr (1,581 days)
0° 13m 39.72s / day
Physical characteristics
Dimensions18.76 km (derived)[3]
18.93±0.9 km[4]
19.77±0.76 km[5]
19.914±0.070 km[6]
5.867±0.005 h[8]
5.87±0.01 h[9]
5.87016±0.00005 h[10]
5.873±0.005 h[11]
0.1048 (derived)[3]
C[12] · S[3]
11.3[4][5][6] · 11.7[1][3] · 12.04±1.20[12]

Orbit and classificationEdit

Jens (yellow-green dots) transists near the center of the Tadpole Nebula.

Jens orbits the Sun in the central main-belt at a distance of 2.1–3.2 AU once every 4 years and 4 months (1,581 days). Its orbit has an eccentricity of 0.22 and an inclination of 14° with respect to the ecliptic.[1] First identified as A922 SC at Simeiz Observatory in 1922, Jens's first used observation was taken at Turku in 1948, extending the body's observation arc by 2 years prior to its official discovery observation.[13]

In 2010, Jens was passing in front of the Tadpole Nebula (see image obtained by WISE).[14]

Physical characteristicsEdit


In September 2000, American astronomer Brian Warner obtained two rotational lightcurves, giving a rotation period of 5.867 and 5.87 hours with a brightness variation of 0.50 and 0.55 magnitude, respectively (U=3/3).[8][9]

In February 2006, photometric observations by French amateur astronomer Laurent Bernasconi gave a concurring period of 5.873 hours with an amplitude of 0.55 magnitude (U=3).[11] This well-defined period was further confirmed by a modeled light-curve using data from the Lowell Photometric Database, giving a period of 5.87016 hours (U=n.a.).[10]

Spectral typeEdit

It is classified as S- and C-type asteroid by the LCDB and Pan-STARRS, respectively.[3][12]

Diameter and albedoEdit

According to the surveys carried out by the Infrared Astronomical Satellite IRAS and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Jens measures between 18.93 and 21.61 kilometers in diameter and its surface has an albedo between 0.085 and 0.149.[4][5][6] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.1048 and calculates a diameter of 18.76 kilometers based on an absolute magnitude of 11.7.[3]


This minor planet was named by the discoverer for his grandson. Karl Reinmuth also named the consecutively numbered asteroid, 1720 Niels, after one of his grandsons.[2] The official naming citation was published by the Minor Planet Center on 20 February 1976 (M.P.C. 3933).[15]


  1. ^ a b c d "JPL Small-Body Database Browser: 1719 Jens (1950 DP)" (2017-05-05 last obs.). Jet Propulsion Laboratory. Retrieved 7 June 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1719) Jens". Dictionary of Minor Planet Names – (1719) Jens. Springer Berlin Heidelberg. p. 136. doi:10.1007/978-3-540-29925-7_1720. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f g "LCDB Data for (1719) Jens". Asteroid Lightcurve Database (LCDB). Retrieved 22 December 2016.
  4. ^ a b c d Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System – IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 17 October 2019.
  5. ^ 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 22 December 2016.
  6. ^ 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". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90.
  7. ^ a b 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 22 December 2016.
  8. ^ a b Warner, B. (March 2001). "Asteroid Photometry at the Palmer Divide Observatory: Results for 706 Hirundo, 957 Camelia, and 1719 Jens". The Minor Planet Bulletin. 28: 4–5. Bibcode:2001MPBu...28....4W. Retrieved 22 December 2016.
  9. ^ a b Warner, Brian D. (January 2011). "Upon Further Review: V. An Examination of Previous Lightcurve Analysis from the Palmer Divide Observatory". The Minor Planet Bulletin. 38 (1): 63–65. Bibcode:2011MPBu...38...63W. ISSN 1052-8091. Retrieved 22 December 2016.
  10. ^ a b Hanus, J.; Durech, J.; Broz, M.; Warner, B. D.; Pilcher, F.; Stephens, R.; et al. (June 2011). "A study of asteroid pole-latitude distribution based on an extended set of shape models derived by the lightcurve inversion method". Astronomy & Astrophysics. 530: 16. arXiv:1104.4114. Bibcode:2011A&A...530A.134H. doi:10.1051/0004-6361/201116738. Retrieved 22 December 2016.
  11. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1719) Jens". Geneva Observatory. Retrieved 22 December 2016.
  12. ^ a b c 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 22 December 2016.
  13. ^ a b "1719 Jens (1950 DP)". Minor Planet Center. Retrieved 22 December 2016.
  14. ^ "Asteroid Caught Marching Across Tadpole Nebula". JPL Photojournal. 13 May 2010. Retrieved 15 November 2015.
  15. ^ Schmadel, Lutz D. "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.

External linksEdit