The Occultation of a 9.4 Star by 2000 DW97

Sept 12, 2025 at 1:24:14am

OWc page

 

This is a bright star, but at low altitude rising in the east. Only 11 degrees up. It's also got a poor RUWE of 3.95, so even if we are well inside the path, a miss is quite possible.

Alt=11, Az=58 in eastern Auriga, below the Pentagon, at about 5 o'clock angle below Capella

 

     

Results:

Kirk and I both got short positives, visually. I was at WestLake, on the west side of the lake, at the clearing shown on GE. Skies were clear, moonless, pretty dark, and looked clean. Karl did not observe due to the altitude and path.

Richard Nolthenius

I observed at 2x, from the north side of the lake, in the middle, about 50 ft SE of the streetlight, on the lake side of Bradley Drive. I saw a lot of noise in the signal, thought it might be due to the image contrast bar setting actually affecting the pixel readings, against my expectations. But no - did two analyses and confirmed that this was not the case. The image contrast bar does not affect the values inside the pixels that are analyzed, only look of them as displayed. The noise appears to be real scintillation at the low 11 degree target star altitude. Even at 2x, the 9.7 mag target star gave some saturated pixels at times, and also true in the reference star just above it. I think in this case that not using a ref star is best. I will use that bright star only as a tracking star in my PyMovie analysis. Experimenting with using as a ref star did not affect readings, as I had to go to such a high smoothing the smoothed curve was quite flat anyway. No clouds or other obscurations.


magDrop report: percentDrop: 97.0 magDrop: 3.824 +/- 0.841 (0.95 ci)

DNR: 3.06

D time: [08:14:24.2229]
D: 0.6800 containment intervals: {+/- 0.0066} seconds
D: 0.9500 containment intervals: {+/- 0.0170} seconds
D: 0.9973 containment intervals: {+/- 0.0359} seconds

R time: [08:14:24.4186]
R: 0.6800 containment intervals: {+/- 0.0066} seconds
R: 0.9500 containment intervals: {+/- 0.0170} seconds
R: 0.9973 containment intervals: {+/- 0.0359} seconds

Duration (R - D): 0.1957 seconds
Duration: 0.6800 containment intervals: {+/- 0.0097} seconds
Duration: 0.9500 containment intervals: {+/- 0.0223} seconds
Duration: 0.9973 containment intervals: {+/- 0.0404} seconds

       

 

Kirk Bender