C/2019 Y4 (ATLAS)

This was my first attempt to photograph Comet ATLAS (C/2019 Y4). Conditions were poor. Heavy clouds prevented photography (and viewing) until after 2AM. This stacked sequence was interrupted by more clouds and high humidity around 3:30AM. By this time, the comet was only about 22° above the horizon (see chart below) and well into the urban light pollution NW of my position. This was somewhat alleviated by the use of the IDAS EOA-1 multi-band filter which includes the major comet emission lines as well as common nebula emission lines.

Chart generated by Sky Safari

Photo info Date/Time: 4 Apr. 2020 ~10:15 UT (03:15 PDT) Location: Vanishing Point Observatory Camera: ASI 1600 MC Cool, Gain=300 (50%), Temp.=0°C Exposure: 22 x 30 sec. Lens: AP 155 (f/7), Borg 1.04x flattener Filter: IDAS EOA-1 Mount: Losmandy Titan Guiding: none Image Processing: Nebulosity/Photoshop/Lightrooom

... and a bit of a "bonus." Earlier in the evening, I felt an earthquake rattle the area (M=4.9), followed by 3-4 aftershocks which I could feel distinctly. Here's what I recorded of the main shock at my home seismometer which is about 150km from the epicenter. Click to enlarge plot.