17 Thetis

Discovery A
Discoverer	R. Luther
Discovery date	April 17, 1852
Alternate designations	A913 CA; A916 YF; 1954 SO1 B
Category	Main belt
Orbital elements C D
Epoch October 22, 2004 (JD 2453300.5)
Eccentricity (e)	0.134
Semi-major axis (a)	369.530 Gm (2.470 AU)
Perihelion (q)	319.991 Gm (2.139 AU)
Aphelion (Q)	419.069 Gm (2.801 AU)
Orbital period (P)	1418.027 d (3.88 a)
Mean orbital speed	18.87 km/s
Inclination (i)	5.587°
Longitude of the ascending node (Ω))	125.622°
Argument of perihelion (ω)	135.906°
Mean anomaly (M)	38.435°
Physical characteristics
Dimensions	90 km
Mass	7.6—1017 kg
Density	2.0? g/cm³
Surface gravity	0.0252 m/s²
Escape velocity	0.0476 km/s
Rotation period	0.5113 d (12.27 h) 1
Spectral class	S
Absolute magnitude	7.76
Albedo	0.1715 2
Mean surface temperature	~173 K

17 Thetis (thee'-tis) is a large Main belt asteroid. It is a S-type asteroid, so it has a relatively bright surface and stony silicate and metallic iron-nickel composition.

It was discovered by R. Luther on April 17, 1852. It was his first asteroid discovery. Its name comes from Thetis, the mother of Achilles in Greek mythology.

One Thetidian stellar occultation was observed from Oregon in 1999. However, the event was not timed.

Aspects

• Thetis Stationary, than retrograde 20.09.2005
  
• Thetis Stationary, than retrograde 24.12.2006
  
• Thetis Stationary, than retrograde 04.06.2008
  
• Thetis Stationary, than retrograde 01.10.2009
  
• Thetis Stationary, than retrograde 08.01.2011
  
• Thetis Stationary, than retrograde 25.06.2012
  
• Thetis Stationary, than retrograde 11.10.2013
  
• Thetis Stationary, than retrograde 24.01.2015
  
• Thetis Stationary, than retrograde 14.07.2016
  
• Thetis Stationary, than retrograde 21.10.2017
  
• Thetis Stationary, than retrograde 11.02.2019
  
• Thetis Stationary, than retrograde 30.07.2020
  
  
  
  
• Thetis Opposition 09.11.2005 1,74593 AU 11,5 mag
  
• Thetis Opposition 08.02.2007 1,61890 AU 11,0 mag
  
• Thetis Opposition 17.07.2008 1,15973 AU 9,9 mag
  
• Thetis Opposition 20.11.2009 1,78755 AU 11,5 mag
  
• Thetis Opposition 21.02.2011 1,53906 AU 10,9 mag
  
• Thetis Opposition 07.08.2012 1,22746 AU 10,1 mag
  
• Thetis Opposition 01.12.2013 1,81341 AU 11,6 mag
  
• Thetis Opposition 08.03.2015 1,45107 AU 10,8 mag
  
• Thetis Opposition 26.08.2016 1,31557 AU 10,4 mag
  
• Thetis Opposition 12.12.2017 1,82324 AU 11,6 mag
  
• Thetis Opposition 24.03.2019 1,35935 AU 10,6 mag
  
• Thetis Opposition 12.09.2020 1,41160 AU 10,7 mag
  

• Thetis Stationary, than proograde 31.12.2005
  
• Thetis Stationary, than proograde 30.03.2007
  
• Thetis Stationary, than proograde 26.08.2008
  
• Thetis Stationary, than proograde 11.01.2010
  
• Thetis Stationary, than proograde 11.04.2011
  
• Thetis Stationary, than proograde 18.09.2012
  
• Thetis Stationary, than proograde 22.01.2014
  
• Thetis Stationary, than proograde 26.04.2015
  
• Thetis Stationary, than proograde 09.10.2016
  
• Thetis Stationary, than proograde 01.02.2018
  
• Thetis Stationary, than proograde 11.05.2019
  
• Thetis Stationary, than proograde 29.10.2020
  
• 
  
  Thetis Conjunction to sun 12.03.2005
  
• Thetis Conjunction to sun 23.06.2006
  
• Thetis Conjunction to sun 19.10.2007
  
• Thetis Conjunction to sun 26.03.2009
  
• Thetis Conjunction to sun 05.07.2010
  
• Thetis Conjunction to sun 08.11.2011
  
• Thetis Conjunction to sun 09.04.2013
  
• Thetis Conjunction to sun 17.07.2014
  
• Thetis Conjunction to sun 30.11.2015
  
• Thetis Conjunction to sun 22.04.2017
  
• Thetis Conjunction to sun 29.07.2018
  
• Thetis Conjunction to sun 22.12.2019
  
• Thetis Conjunction to sun 05.05.2021
  
  
  
  

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