Thursday, March 23, 2017

#78 - Wednesday, March 23, 2017 - My first comet!

Another club member, Ray, was using the memorial scope until about 10:30 PM, and the sky was covered in high clouds anyway, so I did some timelapse looking toward the Orion nebula.  I also tried to set up the Meade refractor that’s on the CGEM mount, but I couldn’t get a guidescope attached to it.  I looked at some things visually through the big Dob the club owns – M42, and galaxies M81 and M82.  I also looked at Jupiter in the memorial scope and club member Mark's SkyBridge.

After Ray left, it was still cloudy, so I decided just to check out a couple visual things while the timelapse went.  I synced to Dubhe in Ursa Major (Jim figured out the bad gotos by the way – using “warm restart” keeps the previous pointing model, which messes up a new night.  So use “cold restart” instead.), and then plugged in the celestial coordinates for Comet 41P/Tuttle-Giacobini-Kresak and went hunting for it with a 38mm eyepiece.  There were a few things that caught my eye, but nothing that really had any discernible nebulosity to it.  So I plugged the camera in and got that all set up, and then went back to the coordinates.  I took a 60-second image – and there it was!  A little fuzzy ball near the center of the frame.  

Comet 41P/Tuttle-Giacobini-Kresak, Nikon D5300, Vixen NA140ssf, Astronomik CLS filter
Guiding: QHY5, Celestron 102mm
11x180s, ISO-3200, no flat (it came out weird)

Because there were still some high clouds, I only did 180-second images, and because it was already so late, I only got 16 before I had to quit.  Also, guiding was not that great so close to the north celestial pole.  I also made a video from the subframes - it spans 48 minutes.
Timelapse GIF of Comet 41P moving through Ursa Major.  Each frame is 3 minutes long, and there are 16 frames, spanning 48 minutes.
[Sorry for the fast speed - I don't think I can control it.  The background brightness difference is from a thin high cloud that rolled through at the beginning.]

Friday, March 3, 2017

#77 - Friday, March 3, 2017 - Some Nights I Stay Up Cashing In my Bad Luck

It looked like it might be clear, so I decided to head out and give it a shot.  I was at my friend Chelsea’s house before, and I got sidetracked talking, so I didn’t get out until about 8 PM.  The moon was less than a quarter, waxing, but still relatively high in the west and was bright enough that I had moonshadows.  However, I couldn’t find anything in the eastern sky to image with the memorial scope (too large of an FOV for many of the small galaxies that winter is good for), so I decided to do at least a high-altitude object – the Flaming Star Nebula.  It had crossed the meridian already, but the memorial scope doesn’t meridian-flip at the meridian – it goes like waaay past it.  So after about four images, while I was inside reading, it stopped tracking at its limit, and I lost about six images or so because I got held up in conversation on Facebook Messenger.  So I went back out and did the flip, but the star field in the picture was not quite the same as before.  I re-synced; same thing.  But I couldn’t quite see the nebula in the subs, at least not on my small tablet with the red filter on, so I just went for it anyway, thinking my tired Friday night brain wasn’t flipping the image right in my head.  Well, I was right – it didn’t quite land on the same star field, and some high clouds came in, and guiding didn’t work that well, so I only had four pictures.  I stacked them, but the SNR was just too low to do much with it.
Flaming Star Nebula, Nikon D5300, Vixen NA140ssf, Astronomik CLS filter
Guiding: QHY5 on Celestron 102mm
4x300s, ISO-1600

Also, I forgot to take biases again, so I took them at home where it was warmer, but I took the wrong ISO.  I also didn’t have cold enough darks – it was like 28 F that night.  30 is close.  Oh well, anyways…hopefully I can image it again soon!