Hurry and Photograph Comet C/2020 F3 Neowise Before It Fades Away!

Earlier this year, there were two hyped comets that made headlines but did not live up to expectations. Then, in June, stargazers held hope that the third comet c/2020 F3 Neowise would deliver a show, and it has surpassed expectations as the best Northern Hemisphere comet in decades.

First, we had Comet Atlas (c/2019 Y4), which was brightening in March, but eventually broke apart in April as it approached the sun. Then, we had comet Swan (c/2020 F8), which was even more promising, as it was a visible magnitude +5 at the end of April with an outburst. As fickle comets often go, Swan quickly dimmed again into a telescope- and binocular-only object. But the third comet, Neowise (c/2020 F3), rapidly brightened at the end of June, made it around the sun intact on July 3rd, and reappeared with an elongated tail as a visible comet! This may be the best visible comet since the Great Hale-Bopp of 1996-1997. 

Observational Report 07/07/2020: St. Augustine, Florida USA 

When the alarm went off at 4:50 am, I debated for a bit whether to get out of bed because the weather forecast had been so poor. This time of year is hurricane season in Florida, so I was expecting to be let down by clouds. As I walked towards my east-facing bedroom window, I could see Venus the morning star shining clear and bright due east in the sky with some haze and light cirrus clouds present, but the clear sky was visible to the ENE.

I grabbed my gear and thought back to my previous attempts to observe and photograph dimmer magnitude 6+ comets that ended up being somewhat underwhelming experiences, so I did not want to get my hopes up. And with the comet only 4-5 degrees high in the sky, I had heard reports that it was difficult to initially spot without using averted vision, a technique sky gazers use to move a dim object away from the center of the eye where the optic nerve creates a blind spot. But I was cautiously optimistic this time would be different. 

I used the iOS planetarium SkySafari the night before with my iPhone to know where to locate the comet. There are many alternatives, including Celestron's free SkyPortal (based on SkySafari) or you can use an online planetarium like TheSkyLive to see where the comet will be for your location and time. On a PC you can use a free program called Stellarium. By July 15th comet Neowise will transition to the evening, rising higher each night after sunset. Hopefully any loss in brightness will be offset as it climbs higher into the sky each night. You can see a chart with the estimated light curve of the comet over time at the TheSkyLive. 

On July 7th 2020 I knew from my planetarium software that at my 29.5N latitude, comet Neowise would only be 5-6 degrees above the horizon in the North East sky. I choose to go to a nearby park on a peninsula that is surrounded by water with clear horizons and a lighthouse that could be used for composition. I got out of the car at 5:15 am and looked NE to where SkySafari had shown the location of the comet in the constellation Auriga, below Capella. There was a clear gap between a bank of low-lying clouds on the horizon, and I was stunned to immediately see the comet easily (without averted vision) with a bright nucleus and streaming tail. For closer observation, I brought a pair of binoculars and a small 80mm refracting telescope that I mounted on my photo tripod. With the additional light-gathering power of the small telescope, I could resolve the yellow-colored nucleus with a dominant jet of dust coming off the top and smaller jet off the bottom! It was a very rewarding experience, behind the total solar eclipse a few years ago and the two fireball meteors I have seen while doing astrophotography. The comet was just above the dark, flat cloud in this snapshot I took with the iPhone 11 before packing up. 

Photographic Reports: 7/07/20, 7/11/20

Around 5:35 am on the morning of July 7th, I could tell the sky was starting to change into blue hour twilight. My best visual observation of the comet had been 75 minutes before sunrise. I replaced the small telescope on the tripod with a Canon 300L f/4, then centered on bright Venus to manually dial in focus with an EOS R using live view at 10x magnification. A Hoya Red Intensifier was used as a light pollution filter. Settings were 2 second shutter delay, ISO 1,600, and 0.8 second exposure time. If I had been setup earlier to photograph, I could have exposed longer, getting more contrast with the faint tail. Compared to tracked deep-sky astrophotography and even Milky Way photography, this was remarkably easy point and shoot. But the resulting image captured at 05:45 am EST was underwhelming. The lesson learned was not to photograph the comet during the blue hour.

On the morning of July 11th I decided to head to the beach and use the St. Augustine Fishing Pier in my composition. The City of St. Augustine Beach has a light ordinance to protect nesting sea turtles, which makes the beach nice and dark for astrophotography. I was ready to photograph at 05:00 am, but had to wait until 5:20 am for the comet to rise above the low lying clouds. Even 70 minutes before sunrise, you can see it was still astronomical twilight. I tracked the sky using an iOptron SkyGuider Pro for 30 seconds, and composited the foreground with a shorter 10 second exposure. Camera settings were 70-200@85mm, f/2.8, iso1600 for both the sky and foreground.

Comet Neowise will be a great photographic target all month. There will be more opportunities to photograph the comet, and results may better for two reasons. The cycle of the moon will be transitioning to a new moon, and the comet will be significantly higher in the sky during actual darkness. The drawback is the comet could begin to fade as it moves further away from the sun. 

The tail is currently 20 degrees long. Keep that in mind when deciding what focal length to use. For example, an 85mm lens with a full-frame 35mm sensor provides a 24.09° x 16.06° field of view. I also highly recommend bringing a pair of binoculars for both locating and appreciating the visual view. Staying away from light pollution is also key. Find a location that does not have red or orange in the direction you will be photographing. LightPollutionMap.info is my favorite resource for this.  

Will you get out and try to capture an image of comet Neowise as it moves back into deep space, not returning again for 6,800 years? If you do, post it in the comments!