Observing as the season turns cold

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Pete
Astro Day Coordinator
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Observing as the season turns cold

Unread post by Pete » Sun Dec 04, 2016 4:50 pm

28 Nov 2016

The sky’s clear today and forecast to stay that way into late evening before rain moves in for tomorrow. I’m out opening up around 17:45 with temperature of 33°F and calm clear conditions with no dew fall.

2016 VY5 is a 574-meter sized Amor now 18.9 magnitude and 0.2 AU distant. Discovered 95 days ago, uncertainty level is 3. Motion is 2.5’/hr. Imaged from 17:52 – 18:27 hrs at 2 minute exposure, 2X2 binning, -15°C cooling, 2 Hz guiding. Using track ‘n stack, frames 1-3, 10-12 & 13-15 show ∆RA = -0.6’ & ∆Dec = +0.5’ Since the sky’s very clear and still S/N is unusually strong at around 13/1 while FWHM is around 4.0”

93P Lovas is a 15.0 magnitude comet now 1.7 AU distant and moving at 53”/hr. Imaged from 18:53 – 19:01 at 1 min, 2X2, -15C, 2 Hz. Frames 1-3, 8-10 & 14-16 show ∆RA = -0.2’ & ∆Dec = -0.75’ S/N approx. 20 and FWHM approx. 4.6”

Image
Comet 93P Lovas 14” LX200 GPS @f/5.9 1 min X 4

37833 is a 7.9 km sized 18.8 mag main belt asteroid in the comet’s field. Movement is 55”/hr. Frames 1-7, 8-14 & 15-21 show ∆RA & ∆Dec = 0
2006 UM is a 1.3 km sized Amor now 16.4 mag and 0.2 AU distant. Imaged from 19:35 – 19:45 at 1 min, 2X2, -15C, 5 Hz. Frames 1, 3 & 5 show ∆RA = -0.1’ & ∆Dec = -.07’ S/N is huge at 32/1 and FHWM tight at 4.0” Photometry suggests 15.8 magnitude (red).

2016 RU17 is a 1.3 km sized asteroid 0.7 AU distant and shining at a dim 19.4 magnitude. Worked it with 3 minutes X 10 frames but couldn’t find a trace of it.

2012 TQ78 is an 869 meter size Apollo now 18.8 magnitude and 0.3 AU distant. Uncertainty level is 2, based upon 200 observations made at 3 oppositions. Motion is 2.3’/hr. Imaged from 20:41 – 20:51 at 150 sec, 2X2, -15C, 3 Hz. Frames 1, 2 & 3 show ∆RA = 0 & ∆Dec = -0.2’ S/N & FWHM values are 5.9/4.0, 7.4/2.2 and 5.8/4.5

16816 is a 3.8 km Apollo in the 2012 TQ78 FOV. Motion is 54”/hr. Frames 1-2, 3-4 & 5-6 show ∆RA & ∆Dec = 0. S/N averages 13 and FWHM is very tight and between 2.2” and 3.2”

It’s down to 30°F. I’m freezing. In at 21:09 with 18 observations transmitted to the MPC.

Conclusions & lessons learned:

The Minor Planet Center rejected the first observation (2012 TQ78) “Date rejected because of departure from GCM. Today (Dec 4) I’ve gone out and analyzed this data and compared the asteroid to the MPC’s calculated position. Rerunning the calculations, stacking 1-2, 3-4 & 5-6 results in a S/N of 10:1 and FWHM or 4.5, and numbers not much more than 1” different than those submitted. The asteroid appeared to be clear of stars. This shouldn’t have been enough to result in an MPC computer hiccup. In fact I’ve submitted data of far weaker S/N. A puzzlement.

The home network failed a week or so ago and the new router may be at fault as I can no longer hold a connection from inside the house with Remote Desktop. Serious problem with winter coming on. I was freezing my tail off out there and tempted to blame the rejected observations on my being too cold and rushing things. Before today’s analysis. After an hour with tech-support in the Philippines the new Linksys dual band router now names both channels the same name but the connection drops out almost instantly when made. Big bummer.

hgp logged 4 Dec 2016
Pete P.
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