Tag: comet

Comets, Sunspots, and Zodiacal Light

There have been few opportunities for capturing night sky objects owing to clouds and the presence of the Moon. That doesn’t stop me from trying.

Comet 12P/Pons-Brooks and Triangulum Galaxy (M33).

Comet 12P/Pons-Brooks and M33 (Triangulam Galaxy).
Comet 12P/Pons-Brooks and M33 (Triangulam Galaxy).

Clouds, a bright waxing Moon, and some distant light pollution made it difficult to capture this comet. This was taken at the base of Arizona Snowbowl ski area at 2830 m; the elevation helps to get above some of the atmospheric haze.

Sunspots AR3615 and AR3614

Several large sunspots are visible on the face of the Sun (27 March 2024).
Several large sunspots are visible on the face of the Sun (27 March 2024).

Zodiacal Light

Zodiacal light, Jupiter, and Comet 12P/Pons-Brooks (28 March 2024).
Zodiacal light, Jupiter, and Comet 12P/Pons-Brooks (28 March 2024).

While setting up to photograph a launch at Vandenberg SFB (which was scrubbed), I fired off a few test shots of the zodiacal light. In review, I noticed that I also captured Comet 12P/Pons-Brooks. Small–very small–when shot with a 24mm wide-angle lens.

Now, the Moon is out of the way and the forecast indicates a few clear nights so maybe I’ll get another change to shoot some images of the comet.

 

Comet 12P/Pons-Brooks

Comet 12P/Pons-Brooks remains in the western sky–visible as twilight fades. But don’t wait too long in the evening or it gets too low in the western sky and becomes difficult to see. Also, it requires long exposure photographs or binoculars/telescope to see. There are projections that it may brighten to become just barely visible to the unaided eye in a few weeks.

Comet 12P/Pons-Brooks on 09 March 2024. This is a single image taken with a 500mm telephoto lens.
Comet 12P/Pons-Brooks on 09 March 2024. This is a single image taken with a 500mm telephoto lens.
Comet 12P/Pons-Brooks and the Andromeda Galaxy (M31) on 04 March 2024. Stack of 13 x 120 second images.
Comet 12P/Pons-Brooks and the Andromeda Galaxy (M31) on 04 March 2024. Stack of 13 x 120 second images.
Comet 12P/Pons-Brooks on 09 March 2024. A stack of images with Max value so that satellite tracks are not removed.
Comet 12P/Pons-Brooks on 09 March 2024. A stack of images with Max value so that satellite tracks are not removed.

I’ve had several opportunities recently to photography the comet including its positioning in the sky near the Andromeda Galaxy (M31). A normal to short telephoto lens (i.e, ~50 to 85mm) was a good choice for capturing both objects while a longer telephoto (i.e., 180mm or even 500mm) worked best for isolating the comet.

Bonus photo: Andromeda Galaxy (M31) taken 13 January 2020.
Bonus photo: Andromeda Galaxy (M31) taken 13 January 2020.

Of course, the comet is not the only object in the sky. Satellites are constantly moving across the sky. Fortunately, software can remove the tracks by stacking multiple photographs and taking the Median or the Mean value at each pixel. On the other hand, it can be useful to take the Max value at each pixel to illustrate the number of satellites crossing even a small portion of the sky in a short period of time.

Comet 144P/Kishuda

Last week I was able to get some good images of Comet 144P/Kushida which was located in the constellation Taurus and near the star Aldebaran. Being this close to a bright star makes it fairly easy to find.

Comet 144P/Kushida on 13 February 2024 while it moved through the constellation Taurus.
Comet 144P/Kushida on 13 February 2024 while it moved through the constellation Taurus.
Screen shot from Stellarium showing the field of view at 500mm.
Screen shot from Stellarium showing the field of view at 500mm.

I first shot using an 80-200mm zoom lens. The short end (80mm) gave me a wide field of view to find the comet and then I zoomed to the long end (200mm). After about a half-hour of shooting I decided to switch to the 200-500mm zoom lens. Starting at 200mm to center the comet, I then zoomed to 500mm. The image above is the result of stacking 22 images (11 minutes exposure time) then post processing with rnc-color-stretch and finally, Lightroom and Photoshop. Above is a screen shot from the sky application Stellarium showing the field of view at 500mm.

The waxing gibbous Moon on 18 February 2024.
The waxing gibbous Moon on 18 February 2024.

Bonus: image of the waxing gibbous Moon a week later. The image was converted from RGB to L*a*b color space and then the two color channels were adjusted to bring out the subtle colors of the Moon.

Comet 12P/Pons-Brooks

This is the first of what will be many posts on this comet. Comet 12P/Pons-Brooks will be in the western sky in the evening for the next few months and could brighten enough to be visible to the unaided eye. Right now, however, it is quite dim at a magnitude of +9.0 and is located near the star Vega in the constellation Lyra.

Comet 12P/Pons-Brooks in the constellation Lyra and near the bright star Vega.
Comet 12P/Pons-Brooks in the constellation Lyra and near the bright star Vega.
Current location of Comet 12P/Pons-Brooks in the solar system.
Current location of Comet 12P/Pons-Brooks in the solar system.
Screen shot from Stellarium showing the location of 12P/Pons-Brooks, Vega, and the constellation Lyra. Rectangle shows the field of view for the 180mm lens.
Screen shot from Stellarium showing the location of 12P/Pons-Brooks, Vega, and the constellation Lyra. Rectangle shows the field of view for the 180mm lens.

Comet 12P/Pons-Brooks is a cryovolcanic comet. When exposed to the sun’s warmth the pressure within this cryomagma builds up until it triggers the release of gases, expelling icy fragments (and the gases) through cracks in the comet’s outer layer and into space. 12P has already had multiple bursts which have resulted in rapid brightening.

I ventured to Sunset Crater Volcano National Monument, an International Dark Sky Park, to shoot images of the comet. As noted above, it very close to the bright star Vega which made it very easy to find. My primary goal was to use my Nikon 180mm f/2.8 AIS lens, a legacy manual focus lens known for value in astrophotography and so that I could capture the full constellation. My secondary plan was to use theĀ Nikon 200-500mm lens at its maximum zoom showing just Vega and 12P.

Owing to being a bit out of practice (it happens), both my focussing and star tracking were suboptimal. Something to work on for my next shoot.

 

 

Comet C/2023 P1 Nishamura

This comet was discovered by Japanese amateur astronomer Hideo Nishimura. It was briefly visible in the morning twilight but became increasingly difficult as it got closer to the sun and was lost in the glare. It will very briefly be the evening sky this week but, again, the glare of the Sun may make it difficult to see.

Here are a few images taken in the pre-dawn hours on 08 September. In the foreground is Wukoki Pueblo in Wupatki National Monument.

Comet C/2023 P1 Nishimura at 0449 MST 08 September 2023.
Comet C/2023 P1 Nishimura at 0449 MST 08 September 2023.
A tight crop of the previous image.
A tight crop of the previous image.
Comet C/2023 P1 Nishimura at 0454 MST 08 September 2023. This is just a few minutes later than the previous image but the sky is already getting very bright.
Comet C/2023 P1 Nishimura at 0454 MST 08 September 2023. This is just a few minutes later than the previous image but the sky is already getting very bright.

Nikon D750, 85mm, f/2.8, ISO 3200, 10×3 seconds and stacked usingĀ Starry Landscape StackerĀ to reduce noise.