C/2014 Q2 overflow

2015 November 01.

2015 November 01/02. Another high atmospheric pressure centred area is giving some opportunity for sky watchers, but as always you "takes you chance"! There was a marked low altitude auroral glow thoughts the dark hours well seen before moonrise on the 1^st November.

Long, clear intervals during the evening and night of the 1^st November, with a little auroral glow, enabled us to image Comet Lovejoy in a dark sky before moonrise. The comet is now over 640 million km from Earth and receding all the time.

 

2015 November 01, 19h 57m UT. Comet Lovejoy Centre) imaged Nikkor 600mm f/4, D300 SLR ISO 2500. Exp. 61.2 sec. The brightest star in the field (dia. 55' approx.) is TYC 2062-606-1 visual mag. 7.28, spectral class G8II-III. Limiting visual magnitude 17.5. (Left click to enlarge.)

 

As will be seen, the comet is no longer circumpolar from Orkney and, with an ever decreasing altitude, it is unlikely we shall be able to follow the comet beyond the end of December, by which time it may be too faint to image with our equipment. Were we to do so, then this will amount to a period of observation of one year.

 

Comet's data for the time of observation:

 

Right Ascension: 16h 51m 5s

Declination: +26° 13' 23"

Constellation: Hercules

Altitude: 24° 40'

Azimuth: 280° 22'

Hour angle: 5h 41m

Rise: 4h 25m 

Transit: 14h 17m

Set: 0h 12m 

 

Elongation: 53.8°

Distance: 4.2836 AU (640.8 million km)

Radius vector: 3.7825 AU (565.9 million km)

Horizontal parallax: 2.05"

 

 

2015 October 29. A small window of opportunity with a clear evening and early night following a day of cloud and rain.

2015 October 29, 18h 23m UT. Comet Lovejoy imaged Nikkor 600mm f/4, D300 SLR ISO 2500. Exp. 25 sec. The brightest star in the field (dia. 50' approx.) is TYC 2066-728-1 apparent visual magnitude 7.85 spectral class: K1III. (Left click to enlarge.)

 

The comet is at the centre of the field showing as faint, bluish haze without a defined nucleus. Not surprising since the comet is now over four times as distant from Earth as is the Sun from Eartrh.

 

Exposures were compromised by the presence of twilight and the presence of the Moon at phase 92/6%, altitude of 1.7°.

 

The trick was to gauge the right time to make the exposure taking into account the two factors of twilight (in the west, where the comet is situated a present in constellation Hercules) and moonlight. This requires judgment for the peculiar circumstances at the time (seeing and transparency being the other two factors); no computer programme will give you this!

 

Data for comet at time of observation:

 

Right Ascension: 16h 47m 46s

Declination: +26° 48' 11"

Constellation: Hercules

Altitude: 38° 17'

Azimuth: 258° 24'

Hour angle: 3h 57m 59s

 

Elongation: 54.8°

Distance: 4.2350 AU (633.6 million km)

Radius vector: 3.7514 AU (561.2 million km)

Horizontal parallax: 2.08"

 

2015 October 08

 

 

2015 October 08, 20h 27m UT. Comet Lovejoy (at centre of field) imaged Nikkor 600mm f/4, D300 SLR ISO 2500. Exp. 53.5 sec. The brightest star in the field (dia. 1.2° approx.) is TYC 2581-1651-1 vis. mag. 8.83 spectral class K2. Limiting mag. 16.0. (Left click to enlarge image.)

 

Exposures were compromised by an all-pervading, moderate auroral glow and "flying auroral patches". (See Auroral page.)

 

Data for comet at time of observation:

 

Right Ascension: 16h 24m 54s

Declination: +31° 34' 15"

Constellation: Corona Borealis

Altitude: 34° 3'

Azimuth: 275° 49'

 

Elongation: 62.3°

Distance: 3.8898 AU (581.9 million km)

Radius vector: 3.5377 AU (529.2 million km)

Horizontal parallax: 2.26"