Asteroids & Comets to close out 2014

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Pete
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Joined: Fri Jun 13, 2003 9:03 pm

Asteroids & Comets to close out 2014

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Tuesday, 30 Dec 2014

It’s a frigid clear winter night, with wind and a bright moon. The dome’s opened and the scope and camera are calibrated prior to dinner, so when I step back out at 17:45 a final focus is all that’s needed. Tonight will be a mixed bag of MPC critical list asteroids plus comets of opportunity. Air temperature is 23°F.

138859 is a 1.1 km sized Apollo now 18.4 magnitude and 0.35 AU distant. Apparent motion is 2.8’/hr and uncertainty level is 1. Imaged from 18:21 – 18:37 hrs at 2 minute exposure, 2X2 binning, -30°C cooling, 5 Hz guiding. Frames 1, 3 & 5 show dRA & dDEC = 0’

Comet C/2014 Q3 Borisov is 12.7 magnitude and only 26° above my NW horizon. Motion is a slow 52”/hr. Imaged from 18:51 – 19:18 hrs at 3 min, 2X2, -30C, 1 Hz. Frames 4, 6 & 8 show dRA & dDEC = 0’. This image is approximately 8’ square and is stacked 5 X 3 minutes. N up and E left.
Image

2014 UR114 is 1.1 km sized Apollo now a dim 19.5 mag and .4 AU distant. Imaged from 19:29 – 19:54 with stacks as deep as 3 X 3 minutes, but the object is ephemeral and the S/N too low to provide valid numbers.

121514 is a 2.7 km sized main belt asteroid now 18.9 mag and .8 AU distant. Imaged from 20:06 to 21:05 hrs, stacking as deep as 5 X 3 minutes. The FOV’s good but can’t locate it.

12143 Harwit is a 9.1 km main belt asteroid in the 121514 FOV. It’s 17.5 mag and has a 0.52 RMS residual. Last observed Oct 2013. Frames 5, 8 & 11 show dRA & dDEC = 0’ and brightness to be 17.3 R.

253849 is a 3 km sized main belt asteroid also in the 121514 FOV. It’s 18.8 mag with an uncertainty level of 1. Last observed July 2013. Frames 1, 3 & 5 show dRA & dDEC = 0’

2005 XM4 is a 757 meter sized Amor now 19.1 mag and .3 AU distant. Uncertainty is 1 and motion is 3.4’/hr. Imaged from 21:15 – 21:30 hrs at 90 sec, 2X2, -30C. Getting chilled so XM4 astrometry is run from inside the house with Remote Desktop. Frames 1-2, 3-4 & 5-6 sow dRA and dDEC = 0’.

C/2014 Q2 Lovejoy is this year’s “Christmas Comet”, and has been climbing higher every night. At present it’s 5.4 magnitude and in a gap through the trees in the low SW. It’s quite visible, but not impressive, in the 80mm finder scope at 30X. Turning back to the main computer to attempt imaging the monitor screen’s blank. Some time’s lost trading out monitors before simply rebooting from a fatal crash. But all observatory settings are good except for recalibration of the adaptive optics. Lovejoy’s motion is pretty quick at 6.6’/hr. Imaged from 22:10 – 22:34 at 5 sec, 2X2, -30C, 1 Hz with 5 second delays so that the simultaneous guiding and imaging don’t trip each other. Frames 2, 17 & 32 show dRA & dDEC = 0’. Stacking 84 X 5 second images:
Image

N up and E left. Lovejoy exhibits a big nucleus perhaps 5 arc-minutes in size, and there are very faint suggestions of rays toward the NE.
1862 Apollo is a 3.7 km sized Apollo discovered back in 1957. Its 17.3 mag and .7 AU distant. RMS residual is .54 and motion is 1.4’/hr. Imaged from 22:47 – 23:46 hrs at 3 min, 2X2, -30C, 4 Hz. It’s down to 21F outside and at this stage I’m working from inside the house. Frames 1, 3 & 5 show dRA & dDEC = 0’, and measured brightness is 17.1 R.

115050 is a 4.2 km sized main belt asteroid in Apollo’s FOV. Mag is 18.6 and distance is 1.2 AU. Frames 1, 3 & 5 show dRA & dDEC = 0’.
2014 WJ96 is a dim dim 19.8 mag main belt asteroid also in Apollo’s FOV. Even stacked 4 X 3 minutes I can’t find it. Quit at 23:46.

In at 23:55 hrs. Air’s down to 20°F. 24 observations submitted to the MPC by midnight. On frigid night like this remote desktop is a wonderful tool indeed.

hgp logged 13:33 hrs, 31 Dec 2014
Pete P.
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