NEOWISE spectroscopy by Damien Lemay

NEOWISE spectroscopy by Damien Lemay

Awarded the prize for ingenuity for the week of August 21, 2020, Damien Lemay won for his images of spectra of Comet C/2020 F3 (NEOWISE).

For the week of August 21, 2020 our Photo of the Week winner wasn’t exactly a photo.

Awarded the prize for ingenuity, Damien Lemay sent in images of spectra of Comet C/2020 F3 (NEOWISE), which he was “barely able to get” on the morning of July 14, 2020.

NEOWISE spectroscopy by Damien Lemay

Lemay said at the top of the graph, one sees the coloured spectrum, shown by the software Basic Amateur Spectroscopy Software (BASS) after wavelength calibration. In the middle, the black and white spectrum as is appears coming out of the camera attached to the Shelyak Lhires III spectroscope. At the bottom, a graph of the spectrum shows the intensity relative to the wavelength.

“One prominent feature of this comet is the sodium doublet, carbon bands (C2) dominate the remaining of the spectrum,” Lemay said. “This was obtained under difficult conditions, the comet was so low that about only half of the telescope could see the comet. The remaining was blocked by the wall of my observatory.

I was hoping to give it a try under better conditions, but NEOWISE’s trajectory was such that it remained out of reach for my spectroscopy set up,” he wrote.

Of the image, one judge noted “this is unique; we don’t see many (if any) spectra.”

“Spectroscopy shows that whether it’s the small stuff here on earth or the big stuff out there, it’s all really the same stuff,” another judge said.

Our honourable mention this week goes to Dan Posey for his wide shot of the Sagittarius region.

Sagittarius region by Dan Posey

“The pandemic hasn’t always been kind to providing opportunities for ‘normal’ astrophotography outings as our shared facilities are not accessible,” Posey wrote. “I decided to test out some new approaches to collect data on those days where it isn’t possible to go out. The biggest challenge in this case was aligning an iOptron Skyguider pro without Polaris and hoping that I could punch through the harsh glare of the car lots below my balcony.”

This image used 42 minutes (84 x 30 seconds) of data of the Sagittarius region, collected using a Canon Ra at ISO 640 and a Sigma 105 at f/1.4.

“This is technically an HOO image as I used a Hutech NB1 drop-in filter, but the channels have not been combined or reassigned,” Posey wrote. “The image was calibrated with bias/flat frames and stacked/processed in PixInsight.”