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Can you see the comet named SWAN? The answer is, with luck, maybe. If we wish to see Comet SWAN, we’ll want some clear nights coming in the next week or so. Here’s a chart with hand-drawn positions of C/2020 F8 (SWAN) over the next month. June 2 would be our best opportunity as the comet will be highest above the horizon and near the star Capella, which will help in finding it. Getting the timing right will be challenging, between twilight fading enough for the faint object to be seen and spotting it before the comet sets! You’ll still need good binoculars to see this one and a clear view to the northwestern horizon. Place your order now for clear skies to be delivered the night of June 2 … DO IT NOW! Supplies are limited.

Chart of Comet SWAN's path May 22 to June 22

Comet C/2020 F8 (SWAN) will make a low arc across the northwestern horizon over the coming month. Here’s a hand-drawn plot. Credit: SkySafari/J. Guilford

Comet SWAN has been a Southern Hemisphere object until just recently. I’ve heard some people here, up north, have caught glimpses of the comet already though it’s so low to the horizon that, even with clear skies, by the time the sky gets dark in the northwest, the comet is setting! And as the days and weeks pass, the progression of the starry background takes everything closer to the horizon — or you could think of the horizon rising, when looking at a chart. Add to that the fact that days are getting longer, sunset and twilight later, the comet lower… ugh! It seems everything’s a race! By mid-June Comet SWAN will be lost in bright twilight.

Comet C/2020 F8 (SWAN) was officially discovered March 25 of this year. It will make its closest approach to the Sun (perihelion) on May 27 when it will be 64 million kilometers from our star. Officially classified C/2020 F8 (SWAN) the new comet was first spotted by Australian amateur astronomer Michael Mattiazzo on April 11 using data from the Solar Wind ANisotropies (SWAN) instrument aboard the NASA/ESA Solar and Heliospheric Observatory (SOHO) recorded on March 25.

If you spot SWAN, please let us know! Good luck!


Comets, being temperamental beasts, don’t always act as we’d expect or hope. Most of the time comets gain brightness as they draw nearer the sun; Comet SWAN has been dimming! I’d seen earlier mentions but this Sky & Telescope article just came out today… HUMBUG!

Photo: Comet 17P/Holmes by James Guilford

Comet Redux. Reprocessing old images shot through the Stephens Observatory telescope shows Comet 17P/Holmes as it appeared October 28, 2007. The two dots are bright stars shining through the comet’s coma. Photo by James Guilford.

Back in 2007 astronomers were excited by a comet known as 17P/Holmes. What was so exciting was that the seemingly ordinary visitor from distant parts of the Solar System suddenly put on a great show. In October, the usually dim 17P/Holmes changed from an unremarkable telescopic object to become visible to the unaided eye, appearing as a yellow “star” in constellation Perseus. It was briefly the largest object in the Solar System. The outburst was believed to be similar to one that took place in 1892 making it visible to amateur astronomer Edwin Holmes, credited with its discovery on November 6 of that year. The reason for the sudden brightening or outbursts remains unknown.

I used my little Canon Rebel XT digital camera attached to the vintage Cooley Telescope at Stephens and attempted to capture images of the comet. The effort and the camera were pretty primitive compared with what we can do now but I got some images and they were the best I could manage at the time. Comet 17P/Holmes faded from visibility over the next several weeks. The somewhat odd appearance of the comet — no classic head and tail — is the result of our perspective: looking straight down its tail instead of from the side.

Recently I viewed a television show about comets and the strange behavior of 17P/Holmes was discussed. That program reminded me of the 2007 apparition and to look at my old images. There wasn’t much image data to work with but I reprocessed what I have and produced a new image a bit better than my first try; that image, shot through our old telescope, appears above.

The “P” in the comet’s designation stands for periodic, meaning after a period of time 17P will return to loop, once again, around Sun. In March 2014 (a seven-year period) the loop was made without an outburst. The next close approach to our Sun, perihelion, will take place on February 19, 2021. Will we be treated to another show?

— James Guilford

Illustration: Jupiter and His Moons as They will appear April 22, 2017, 10:00 PM EDT

Simulation: Jupiter and His Moons as They will appear April 22, 2017, 10:00 PM EDT

FINAL UPDATE: In all, 18 people and one dog took a chance on the changeable skies and paid the observatory a visit. Cloud cover ebbed and flowed, changing Jupiter’s appearance through the telescope. Interestingly, some of the better views of the planet actually occurred when thin clouds dimmed the brilliant planet cutting the glare. Viewers could make out the gas giant’s two major temperate cloud belts and sometimes one or two more! The four Galilean Moons were visible nearly all of the time. Owing to generally poor viewing conditions, the evening was limited to Jupiter only – dimmer objects were not available. The April 22 program will be repeated in May, given clear skies. By the way, before the dog came, a cat arrived with one of our visitors but refused to come inside, so kitty didn’t count!

UPDATE: Saturday, 9:00 PM: Opened when we could see Jupiter through thin clouds but expect the sky will cloud over again before clearing in the wee hours. Check out Twitter feed to the right for updates and closings…

UPDATE, Saturday, 4:00 PM: Forecasts call for partly- to mostly-cloudy conditions tonight. A final go/no-go decision on opening will be made later but, if we do open, we DO NOT expect to be able to see dimmer objects such as star clusters or the comet listed below. More later….

Stephens Memorial Observatory of Hiram College will be open for public observing Saturday, April 22, from 9:00 to 11:00 PM. This will be the first scheduled Open Night of the 2017 season. The “star” of the night will be planet Jupiter, brilliant in our southeast sky. We will also seek out the M3 star cluster and, later, the Hercules Cluster and (with some luck) Comet C/2015 V2. Other objects of interest may also be viewed. Of course, all of the night’s observing depends upon clear skies and those have been in short supply this spring!

Cloudy skies at the starting time cancel the event and, in that case, the observatory will not open. No reservations are required and there is no admission fee for observatory public nights.

The Observatory is located on Wakefield Road (Rt. 82) less than a quarter of a mile west of Route 700 in Hiram. There is no parking at the Observatory. Visitors may park on permissible side streets near the Post Office, a short distance east of the observatory.