Tag: light pollution

Comet C/2021 A1 (Leonard)—IV

It’s been awhile since the last post about the comet—but cloudy skies with lots of rain and snow have made observations difficult. Finally, we had a break in the weather on New Year’s Day and I was able to capture additional images.

The comet has dropped lower in the sky making it difficult to get good images because the comet is now located in the band of twilight glare. Only at the end of astronomical twilight is the sky dark enough but by this time the comet is very low on the horizon leaving only minutes to shoot until it sets.

Below are two images of the comet. The first is a set of images taken between 1832 and 1850 MST. The best 30 images were combined and averaged in Starry Sky Stacker then histogram stretched using rnc-color-stretch. Individual images were shot at 85mm, ƒ/4, ISO 100, and 15 seconds. The resulting image shows the tail extending nearly to the upper left corner.

Comet C/2021 A1 (Leonard) at 1832–1850 MST 01 January 2022.
Comet C/2021 A1 (Leonard) at 1832–1850 MST 01 January 2022.
Comet C/2021 A1 (Leonard) at 1901 MST 01 January 2022.
Comet C/2021 A1 (Leonard) at 1901 MST 01 January 2022.

The second image is a single image taken at 1901 MST at 85mm, ƒ/1.8, ISO 500 and 30 seconds. This image shows how close the comet was to the horizon. The glow at the bottom of the image is the light dome from Phoenix about 200 km to the south.

The comet is moving away from us and lower in the sky. I’m not certain I will be able to get another chance to capture any images. For those in the southern hemisphere, the comet is better placed in the night sky for viewing and photography and there have been some amazing images captured. Spaceweather.com noted that “…Intense solar heat has given the comet one of the most beautiful tails astronomers have ever seen…”

 

Light pollution in the night sky

Earlier this month it was apparent that there would be one final night of exceptionally clear skies before the summer monsoon pattern set up and skies would be cloudy more often than clear. I thought another night sky image with reflections of the stars in water might be interesting so I ended up at Lake Mary a few miles southeast of Flagstaff. I was surprised to see how much light pollution there was in the southern sky. This stray light is coming from Phoenix, located over 100 miles to the south. There is so much light that it is even reflected in the lake — as are a few of the stars.

Light pollution from distant Phoenix
Light pollution from distant Phoenix

A very short distance to the north of where this image was taken is the Anderson Mesa astronomical station. It’s hard to believe that they can still gather useful observations of the sky with this much light pollution. Finding truly dark skies is becoming a global challenge.