691 Lehigh

691 Lehigh

Discovery
Discovered by	Joel Hastings Metcalf
Discovery site	Taunton, Massachusetts
Discovery date	11 December 1909
Designations
MPC designation	(691) Lehigh
Pronunciation	/ˈliːhaɪ/ [1]
Alternative designations	1909 JG
Orbital characteristics [2]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc	101.40 yr (37038 d)
Aphelion	3.3787  AU (505.45  Gm)
Perihelion	2.6443 AU (395.58 Gm)
Semi-major axis	3.0115 AU (450.51 Gm)
Eccentricity	0.12194
Orbital period (sidereal)	5.23 yr (1908.9 d)
Mean anomaly	189.349°
Mean motion	0° 11m 18.924s / day
Inclination	13.010°
Longitude of ascending node	87.997°
Argument of perihelion	304.466°
Physical characteristics
Mean radius	43.84±0.85 km
Synodic rotation period	12.891  h (0.5371  d)
Geometric albedo	0.0438±0.002
Absolute magnitude (H)	9.2

691 Lehigh is an asteroid orbiting the Sun in the asteroid belt, discovered in 1909. ^[3] It is named after Lehigh University, where its orbit was calculated in the Masters Thesis of Joseph B. Reynolds, following the observations of amateur astronomer Joel Metcalf. The asteroid is a CD:-type asteroid, suggesting its surface is largely carbonaceous, with many primitive molecules similar to those of comets. Due to this, it has a cometlike surface albedo of just 0.05, similar to fresh asphalt, meaning that it reflects only 5% of light that hits it. Lehigh is not known to be a member of any collisional asteroid family.

References

1. Noah Webster (1884) A Practical Dictionary of the English Language
2. "691 Lehigh (1909 JG)". JPL Small-Body Database . NASA/Jet Propulsion Laboratory . Retrieved 5 May 2016.
3. "(691) Lehigh". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. 2007. p. 67. doi:10.1007/978-3-540-29925-7_692. ISBN   9783540299257.

External links

• Planet Lehigh: Early Astronomy, Lehigh University – Special Collections
• Lightcurve plot of 691 Lehigh, Palmer Divide Observatory, B. D. Warner (2009)
• 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
• 691 Lehigh at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris  · Observation prediction  · Orbital info  · Proper elements  · Observational info
• 691 Lehigh at the JPL Small-Body Database
  • Close approach  · Discovery  · Ephemeris  · Orbit viewer  · Orbit parameters  · Physical parameters