Astronomy

2015 January 18. Comet C/2014 Q2 Lovejoy.

A short clearance enabling the comet to be imaged against a relatively dark sky and thus showing the delicate, faint tail to good effect. Fair transparency but poor seeing, accounting for poor stellar images.

2015 January 18, 19h 18m UT. A 6 sec. exposure Nikkor 50mm f/1.8, D100 ISO1000; field 16.5° x 25°. Pleiades Cluster to the left. (Static camera.) The comet's position is ringed.

2015 January 18, 19h 22m UT. A 27 sec. exposure Nikkor 500mm f/4, D800 SLR ISO 2500.  The brightest star in the field (dia. 1.8° approx.) is STF 366 mag.: 6.77 spectral class K0.  The star a little to the left of the comet (coma) is TYC 1231-811-1 mag. 7.22 spectral class K0. 

Local and positional data for the comet at 19h 22m:

Right Ascension: 3h 11m 18s

Declination: +21° 59' 34"

Constellation: Aries

Altitude: 52° 49'

Azimuth: 176° 36'

Hour angle: 23h 51m 10s

Rise: 10h 45m 22s 

Transit: 19h 31m 39s

Set: 4h 21m 48s 

Elongation: 112.9°

Distance: 0.5512 AU (82.5 million km)

Radius vector: 1.3018 AU (194.8 million km)

Horizontal parallax: 15.95"

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