Comet SWAN is expected to grace northern skies in the days to come.

Comet SWAN
Comet SWAN (C/2020 F8) displays a spectacular ion tail about 8° long pointing southwest on May 2nd. For additional updates on the comet please go to my Astro Bob blog.
Damian Peach

When Comet ATLAS (C/2019 Y4) began to fragment and fade in April our hopes for a bright comet this spring appeared quashed. But just in the nick of time Comet SWAN (C/2020 F8) came to the rescue, shooting across the sky faster than a speeding bullet and wearing a magnificent green cape to boot! Discovered in images taken by the Solar and Heliospheric Observatory's SWAN (Solar Wind Anisotropies) camera on March 25th by Australian amateur Michael Mattiazzo the comet has brightened by leaps and bounds. As of May 5th, the newcomer had climbed to magnitude 5.2 with a 1° visual tail that lengthens to a luxurious 6–8° in photographs.

Hubble's view of Comet ATLAS breaking apart
The NASA/ESA Hubble Space Telescope has provided astronomers with the sharpest view yet of the breakup of Comet ATLAS (C/2019 Y4). The telescope resolved roughly 30 fragments of the comet on April 20th and 25 pieces on April 23rd.  The comet was first discovered in December 2019 by the ATLAS (Asteroid Terrestrial-impact Last Alert System) survey.
NASA / ESA / D. Jewitt (UCLA) / Q. Ye (University of Maryland)

While ATLAS continues to hang on at magnitude 9, photos taken by both amateurs and the Hubble Space Telescope clearly show a nucleus in turmoil, shattered into dozens if not hundreds of pieces. Why is uncertain, but according to a recent Hubble press release the original nucleus may have spun itself into pieces because of uneven outgassing from sublimating ices. Picture the comet as a punching bag for the jets of gas and dust blasting willy-nilly from its nooks and crannies. While the future of ATLAS is dim (pun intended), both amateurs and professionals are finding its unraveling a rare glimpse into the nature of comets as fragile agglomerations of crystal and dust.

Comet SWAN composite
This montage shows the increase in brightness and complexity of Comet SWAN between April 13th and 30th of this year when its magnitude brightened from 7.8 to 5.2.
Justin Tilbrook

First taste of SWAN: Morning appearance

Southern Hemisphere observers have the best seats for viewing the comet in early May but that will change as SWAN moves rapidly northward. This week, observers in the southern U.S. should get their first glimpse of the comet very low in the eastern sky during morning twilight as it speeds from Cetus into Pisces. The comet's height above the eastern horizon will vary depending on latitude, with more northerly latitudes favored from about May 20th through early June. Peak magnitude of 2.8 is expected around May 21st.

Comet SWAN will cruise low across the east and northeastern sky from mid to late May. Its position is shown every three mornings at around 4:30 a.m. Central Daylight Time. Use the brighter stars Algenib in the bottom of the Great Square along with Mirach and Almach in Andromeda and Mirfak in Perseus to help point the way. In binoculars Comet SWAN will look like a small, fuzzy spot with possibly a faint tail visible. Stellarium with additions by the author

While northern viewers will get a modest altitude bump, twilight also begins earlier — 2 to 2½ hours before sunrise compared to 1 ½ hours for the southern U.S. — so any elevation gains may well be offset by skyglow.

Comet SWAN animation
Continuous changes in the structure of Comet SWAN's ion tail are seen in this animation made on May 1st.
Gerald Rhemann

If the 3rd-magnitude comet were visible in a dark sky even suburban observers would snag it. But because SWAN never gets far from the Sun during the best part of its apparition and constantly flirts with twilight I strongly suggest using a pair of binoculars. Once you've found it lower the glass and see if you can spot the comet without optical aid.

Comet SWAN chart
The comet rides a rollercoaster from Cetus to Auriga in just three and a half weeks. Its position is marked each day at 0h UT. Subtract 4 hours to convert UT to Eastern Time; 5 hours for Central; 6 hours for Mountain; and 7 for Pacific while also moving the date back one day. For example: 0h UT May 15th = 8 p.m. on May 14th EDT. Click on the image for a larger version of the chart and here for a black-and-white PDF.

On May 12th the comet will breeze some 83 million kilometers (52 million miles) from Earth and come to perihelion on May 27th at a distance of 64 million kilometers (40 million miles) from the Sun. During the second week of May SWAN will stand just a few degrees high in the eastern sky 90 minutes to 2 hours before sunrise for the central U.S. By May 21st its altitude increases to around 5° and subsequently declines at month's end.

Evening appearance: A better show

Evening position of Comet SWAN in June
This map depicts the comet's evening apparition from 40°N latitude. The bright stars Capella and Mirfak will help point the way. Positions are marked every three nights at 10:30 p.m. CDT.
Stellarium with additions by the author

The comet also has an evening sky apparition that overlaps with its morning appearance. From about May 23rd to June 10th observers at mid-northern latitudes can catch the comet in a dark sky at the end of evening twilight as it glides from eastern Perseus into Auriga. On the 23rd it will only stand about 3° high at dusk's end but that increases to 7° by the 28th. The northern U.S. will have a slightly longer period of visibility. Although SWAN fades from magnitude 2.8 to 5 during this time it's visible during convenient evening hours and with less twilight interference.

If you're out at dawn find a location with a view as close to the east-northeastern horizon as possible. Evening observers will need to secure a spot with a horizon to the north-northwest. When seeking a location for viewing a special celestial treat like a comet I'll explore both Google Maps (click on the Satellite View box for a photographic map) and the Light Pollution Map to find a convenient dirt road or field open in the key direction.

The comet's orbit is inclined 110.8° so it loops steeply up and over the plane of the planets (above Earth's North Pole). Comet SWAN's position is shown for May 12th when it passes closest to the Earth. Its orbital period is not yet known with precision but ranges in the thousands to millions of years.
NASA / JPL / Horizons

The altitudes above refer to the head of the comet but it's likely that SWAN will develop a long, bright tail pointing up and away from the Sun. What a beautiful sight that would make in binoculars! Not to mention a tempting target for wide-field astrophotography. Comet SWAN makes several close passes of deep-sky objects and bright stars during its run, including a near miss of the 10th-magnitude galaxy NGC 925 in Triangulum (May 17th). It comes within 0.5° of Algol on the 20th and then sails 1° south of Capella on June 2nd.

I think this comet is something to get excited about. If it can keep it together we're in for a wonderful show. And all before the mosquitos come out in full force. Who could ask for more?

Although COVID-19 concerns mean we have to keep our distance from one another I would encourage you to share the comet in small groups in safe fashion. Each person (or family) who wants to attend your viewing session would drive their own car to the observing location and watch with their own pair of binoculars or telescope. Once everyone's out of their vehicle — and keeping at least the requisite 6 feet apart — you can explain where to look and then enjoy the sight together within earshot of one another in this unique form of "remote observing."

Seriously, another bright comet

Yet another recent comet discovery has bright prospects. Comet NEOWISE (C/2020 F3) was found in March by NASA's NEOWISE project, the asteroid-hunting division of the Wide-field Infrared Survey Explorer (WISE) mission. It currently glows at magnitude 11 with a strongly condensed coma 5′ across. The new object is scooting north from Lepus into Orion and only visible in the Southern Hemisphere for the moment. It will disappear in the solar glare in early June and then return to the dawn sky in Auriga for Northern Hemisphere observers in July. Although the comet will remain low in morning twilight, it's expected to reach magnitude 3 or 3.5 by mid-July as it works its way from Lynx to Ursa Major.

Tighten your seat belts!

(Check out my Astro Bob blog for regular updates on SWAN and a host of additional comets making appearances this spring and summer.)

Comments


Image of Joe Stieber

Joe Stieber

May 6, 2020 at 2:20 pm

I hate to be a wet blanket, but the magnitude estimates at COBS...

https://cobs.si/analysis2?col=comet_id&id=1876&plot_type=0

show C/2020 F8 (SWAN) reaching a plateau in the high 4's during the first few days of May 2020, but now (May 6), the curve seems to be in a slightly downward trend with magnitudes at the mid-5 range. I truly hope this apparent drop in brightness is just a hiccup on the way to a peak around magnitude 3.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 6, 2020 at 3:04 pm

Hi Joe,
Thank you for sharing that. Yes, I noticed a slight downward slide of a couple tenths of a magnitude in the past few days. Let's hope that it doesn't become a trend. But if it stalls even a 5th magnitude binocular comet would be nice to look at.

You must be logged in to post a comment.

Image of mark seibold

mark seibold

May 6, 2020 at 8:02 pm

Great article Bob!
This is the most encouraging news that we have seen since the days, or the likes of Comet Hale-Bopp in April 1997.
I've been trying to log into the Sky and Telescope site for some time, and finally just accomplished it again, as one of your associate editors just published my large lunar technical pastel sketch of the moon for the May 2020 issue gallery on page 75.
However I photographed dozens of comets over the past 30 - 40 years. [If only as a modest to slightly advanced amateur, originally just using my 35mm film camera, from my college days in 1973.] More recently I photograph the Comet Lovejoy, high overhead in the evening skies with some success using a Celestron 5 inch Cassegrain, and my Sony NEX 5r mirrorless camera riding piggyback atop the telescope with its reasonable equatorial tracking, in January of 2015. [I've just updated that as my new profile photo here for my log in to S&T.]
This viewing window with Comet SWAN will be quite a photo opportunity in the early morning skies by mid to late May 2020, as the comet will nearly pair up with the Andromeda Galaxy.
I'm going to share your great article here now with my other Facebook friends, to inform them of this first great opportunity for them to finally see a visible comet.
*I'm not sure that I can attach a photo compilation of about eight bright comets that I've photographed over the past 44 years, but I'm going to see if there's an attachment available here for photos. I'm doing this a course for the encouragement of others to get out and observe, can easily photograph with digital cameras soon, Comet SWAN.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 6, 2020 at 11:05 pm

Great to hear from you, Mark. And thank you for the kind words. Congratulations on the publication of your lunar sketch — that's fantastic! When you get a photo of the comet please send it along so we can share it.

You must be logged in to post a comment.

Image of Yaron Sheffer

Yaron Sheffer

May 6, 2020 at 4:56 pm

Hi Bob,

Hmmm... a comet moving faster than a speeding bullet. Is that slower or faster than an asteroid moving as fast as a roadrunner? A conversion chart between these units would be helpful 😉

You must be logged in to post a comment.

Image of Bob King

Bob King

May 7, 2020 at 2:32 pm

Hi Yaron,
Ha! That's a good one. Humor much appreciated.

You must be logged in to post a comment.

Image of shashikolar

shashikolar

May 6, 2020 at 6:04 pm

Hi Bob,

Great article, as usual.

Why aren't we seeing dust tails for these comets? Usually, they are brighter than ion tails. Sky Safari shows tails pointing directly away from the Sun for 58P/Jackson-Neujmin and C/2019 Y4 (ATLAS). I'm guessing they are ion tails too.

Thanks,
Shashi

You must be logged in to post a comment.

Image of Bob King

Bob King

May 6, 2020 at 10:56 pm

Hi Shashikolar,
I do not know this for a fact, but it's very possible there is a significant dust tail but due to the comet's current geometry it may be hidden from view behind the coma. As the geometry changes that tail — assuming it is there — may very well come into view. I invite other more familiar with this comet's geometry to further comment on your question.

You must be logged in to post a comment.

Image of Rod

Rod

May 6, 2020 at 6:59 pm

Bob King report stated "The comet's height above the eastern horizon will vary depending on latitude, with more northerly latitudes favored from about May 20th through early June. Peak magnitude of 2.8 is expected around May 21st."

This morning near 0504 EDT, in my area (38-39 degrees N) it was close to 3 degrees altitude and 97 degrees azimuth in Cetus, however, the weather here is cloudy and rainy at times. Tomorrow morning may be better but that low elevation indicates to me, not likely visible unless you have a really, *flat* view of the eastern sky . Stellarium 0.20.1 allows you to update the latest comet elements and I did. Starry Night already has them from the mother ship server. On 21 of May near 0504 EDT, the comet will be about 12 degrees up in Perseus, close to 45 degrees azimuth for my location but sunrise is near 0550 EDT too. I may have a go for this comet using my 10x50 binoculars later, early morning mountain bike ride to an overlook area with plenty of E-NE sky visible.---Rod

You must be logged in to post a comment.

Image of Bob King

Bob King

May 6, 2020 at 10:57 pm

Hi Rod,
When you see it, please write back. We are very interested to hear your impressions.

You must be logged in to post a comment.

Image of Zubenelgenubi 61

Zubenelgenubi 61

May 6, 2020 at 9:22 pm

I think SWAN is now totally jinxed. :-). There does seem to be a lot of potential here- pretty condensed, photogenic with a nice, long gas tail, and it will be at its best when near a zero magnitude star, unlike the three comets buried in the Camelopardalis desert, and at a convenient hour for most people. But there is also plenty on the bad side. Hopefully the plateau or even decline over the last few days is the winding down of an outburst rather than something else... the end of the beginning rather than the beginning of the end. Unfortunately, although in a good spot in the sky, the comet will be mired in the twilight much like PanSTARRS was a few years ago. Although PS may have become as bright as first or even zero magnitude, that was not enough to make it stand out in the dusk sky.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 6, 2020 at 10:50 pm

Hi Zuben,
Well, we must just wait and see. But hey, I beg to differ about Panstarrs 🙂 Maybe it doesn't take that much to get me going but I thought that one was a real gem of a comet even though it was also trapped in twilight. Wonderful in binoculars and I'll never forget its brilliant yellow false nucleus in my little refractor.

You must be logged in to post a comment.

Image of Zubenelgenubi 61

Zubenelgenubi 61

May 6, 2020 at 11:05 pm

It wasn't bad, I agree, but twilight reduced what might have been a Great Comet in total brightness to a garden variety.object. Actually, I think the best view was when PanSTARRS was close to the Andromeda Galaxy a few weeks after closest approach.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 7, 2020 at 11:24 am

Zubenel,
Yes, that was a beautiful pairing. I spent a good part of an evening doing wide-field photography of the two with a telephoto lens.

You must be logged in to post a comment.

Image of bob kelly

bob kelly

May 7, 2020 at 8:11 am

Thank you for the evening sky map.
I was following SWAN on theskylive and had the evening viewing in my monthly column for the Westchester Astronomers. I did a 'stop the presses' on the newsletter when my other sources only had the mid-month view in the morning.
It's both!
I think I'll have a better view in the northwest sky, if SWAN holds together.
bob k

You must be logged in to post a comment.

Image of Tom-Reiland

Tom-Reiland

May 7, 2020 at 10:15 am

Bob, I was just going through the BAA Comet Webpage and one of the sections has an observation listing the magnitude of the Comet at 5.7 magnitude. The observer is in Australia. It may be dud #2 for 2020. I hope not, but it does not look good.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 7, 2020 at 11:30 am

Hey Tom,
I'm not throwing in the towel. Yet. Full moonlight reduces the apparent diameter of the comet's coma which might cause some observers to underestimate its brightness. But yes, it could also be plateauing or even fading which would be bad news. I'm eager for a look!

You must be logged in to post a comment.

Image of CraftyGramZ

CraftyGramZ

May 13, 2020 at 8:55 pm

Thank you for this website information. I know nothing about this subject but last night May 12,2020 between 10 and 10:15 PM I saw the most beautiful comet. It was very bright surrounded by green and had a very long tail. I am in Fort Mohave, Arizona and was facing northwest. It was fairly low in the sky. It was very large from my perspective a bit smaller than a soccer ball. I tried to get my daughter to look up in time but it was just too fast. She missed it. I cannot find anything regarding last nights occurance. From what I can find on the internet the comet Swan is passing near but everything says pre-dawn. I would love to see this again but cannot find anything that tells me what time. I have never seen a comet before, I am assuming that is what it was from the photos online, and this was the most beautiful thing I have seen in my 77 years! Can you confirm what it was and if I might be able to see it again.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 14, 2020 at 12:21 pm

Hi Crafty,
Such an exciting observation! But I must tell you that you saw a fireball (a bright meteor) and not the comet. They have similar shapes with a bright head and long tail but a fireball is a small bit of rock from an asteroid burning up in Earth's atmosphere while a comet is a kilometer-wide hunk of dusty ice many millions of kilometers away. The bright tail is made of dust and gas vaporized from the comet and illuminated by the Sun. You'll find maps and times to view the comet in the over the coming 2-3 weeks in the article I wrote. Thank you for sharing your observation!

You must be logged in to post a comment.

Image of CraftyGramZ

CraftyGramZ

May 14, 2020 at 10:36 pm

Thanks Bob, I thought it was for sure the comet since it was green with a yellow inside and looked like the photos I later found online. I have been trying to research comets to find a site with better time, date and location but just haven't found much. Going to buy some binoculars and keep looking.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 15, 2020 at 11:44 am

Crafty,
The article I wrote here (https://skyandtelescope.org/astronomy-news/comet-swan-expected-to-put-on-a-splendid-show/) provides maps to find the comet both morning and evening and times. I think it be very helpful to you. Look it over, and if you have any questions, just ask.

You must be logged in to post a comment.

Image of Tom Hoffelder

Tom Hoffelder

May 14, 2020 at 3:40 pm

Oh, me too! And I'm hoping NEOWISE survives to be a real naked eye comet!

You must be logged in to post a comment.

Image of Bob King

Bob King

May 14, 2020 at 5:59 pm

Hi Tom,
Yes, me too! And there's another waiting in the wings as well — C/2019 U6 Lemmon. Probably not naked eye but a July a.m. treat.

You must be logged in to post a comment.

Image of Ali-Ebrahimi Seraji

Ali-Ebrahimi Seraji

May 8, 2020 at 5:39 am

Hi Bob,
I'm looking forward to another bright comet appearing in the sky. I failed in my first attempt in the morning 7 May. I got help from the star Alpha Pegasus. I couldn't see with the 20x80 binoculars. In Iran, it is still a little higher than the horizon.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 8, 2020 at 11:17 am

Hi Ali,
Great to hear from you and good luck! Send a photo if possible when you make your sighting.

You must be logged in to post a comment.

Image of Ali-Ebrahimi Seraji

Ali-Ebrahimi Seraji

May 12, 2020 at 9:06 pm

Hi Bob,
On the morning of May 13, the weather was very clear. I was able to see the comet in the dawn with 20× 80 binoculars. It has a small foggy core. Its Magnitude was 6.

You must be logged in to post a comment.

Image of Craig

Craig

May 8, 2020 at 8:16 pm

Up here in the Upper Peninsula of Michigan, Capella is circumpolar for us. The head if the comet will just barely clear the horizon, but the tail will hopefully be easily seen all night long. We have excellent dark sky locations looking north along the southern shore of Lake Superior. The snow might even be gone by then. We got 2” today.

You must be logged in to post a comment.

Image of Percy-Jacobs

Percy-Jacobs

May 9, 2020 at 6:40 am

Hi all from down here in South Africa. We are busy saying goodbye to comet sawn. It has entertained us for a few weeks. It's been showing itself low on our eastern horizon and visible from about 03:00 in the morning until twilight which was at around 05:15. We now hand over to colleagues in the North. Have fun and enjoy. If you want, I could send you a map showing its orbit in our southern skies and a story on my low-resolution spectra of the comet clearly showing the "C2 swan bands".
Regards
Percy

You must be logged in to post a comment.

Image of Bob King

Bob King

May 9, 2020 at 3:02 pm

Dear Percy,
Thank you for your offer! Would it be possible to send the photo of the low-resolution C2 spectra to me? E-mail: [email protected]

You must be logged in to post a comment.

Image of Claudio-Martinez

Claudio-Martinez

May 9, 2020 at 7:33 am

Hello Bob:

Since 4/26 the comet shows a strange light curve, and we began to follow it with a 40 cm reflector. In yesterday's photos, the core is broken. If you want, I send you the photos. Cheers!
My email: [email protected]

You must be logged in to post a comment.

Image of Bob King

Bob King

May 9, 2020 at 3:00 pm

Dear Claudio,
That's an exciting but not exactly welcome development. Yes, please send me the photos Claudio and I will update the blog. Thank you!

You must be logged in to post a comment.

Image of Zubenelgenubi 61

Zubenelgenubi 61

May 11, 2020 at 2:18 pm

I don't know of a breakup, but the fall by one magnitude when SWAN normally should be brightening is consistent with the subsiding of earlier outbursts that raised everyone's hopes. I thought even the predicted third magnitude was not enough for SWAN to put on much of a show given the low altitude and twilight- now it is likely to be fifth or sixth magnitude at its supposed peak. Probably hard for the general public to find from near the city. Still worth a try from dark sites if you can get there, and great images can possibly be obtained if you have the equipment. I think hopes of a really good show are gone unless we get another outburst.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 12, 2020 at 11:51 am

Zuben,
Yes, disturbing news about SWAN's fade to mag. ~5.5. That definitely will put a crimp on viewing but it will still be the brightest comet since Wirtanen. I still remain hopeful for another outburst.

You must be logged in to post a comment.

Image of Tom Hoffelder

Tom Hoffelder

May 11, 2020 at 4:01 pm

Two in a row bite the dust! From our friend Seiichi, "It brightened up to 4.7 mag in early May (May 2, Marco Goiato). However, the brightness evolution has stopped after that. Now it is 5.5 mag (May 8, Marco Goiato). It will approach to Sun down to 0.43 a.u. on May 27, and it was expected to brighten up to 3.5 mag. But actually it may be 5 mag at best." Today's estimates on COBS average 5.8. Wish I had checked this before working hours last night on when/where I should watch. Well, I guess I might at least be able to see it and add it to my list as #151. On the positive side, it could be a four comet night, even five if we count 2019Y4-A as one. And in other news, I think there are now possibly four SN in range of my C14!

You must be logged in to post a comment.

Image of Bob King

Bob King

May 12, 2020 at 11:47 am

Hi Tom,
Yes, it does appear to be fading a bit instead of brightening more. Still, I'll take a 5th magnitude comet in a minute.

You must be logged in to post a comment.

Image of SNH

SNH

May 12, 2020 at 7:45 am

Great article. I live at 36.1 N and at 10h UTC on May 9th I tried to see the comet with my 12x60 binoculars and 130mm telescope. The temperature was 39 degrees (F) and I could see the Cygnus Star-cloud overhead even with the nearly full moon, so I thought I had my clearest conditions for looking right along the horizon. I even had some great guide stars like Delta Piscium but alas could not make it out. I tried my best. I hope others can see it, but I'll try again in a day or so. It's not going to be naked-eye it seems, but I still hope to see it in binoculars.

Scott

You must be logged in to post a comment.

Image of Bob King

Bob King

May 12, 2020 at 11:44 am

Thank you so much Scott for sharing your observation. It was still very low at the time. Visibility will improve in the coming days. It's concerning that the comet appears to have faded a bit and stalled at magnitude 5.8. Let's hope it turns around again.

You must be logged in to post a comment.

Image of Randy Pfeiffer

Randy Pfeiffer

May 12, 2020 at 12:41 pm

This morning's observation of Comet SWAN was unsuccessful from SE of Phoenix at 33.2N from 11:00 through 11:30 UTC. Not visible in 10x50 binoculars or a TV-85. The skies near the eastern horizon were somewhat hazy from the previous day's rainfall. I hope tomorrow will turn out better. It's disappointing to see its magnitude continue to grow more dim as it approaches perihelion, when it typically would become brighter.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 12, 2020 at 2:17 pm

Thanks, Randy for the heads up. Up here in Minnesota I'll make my first attempt on the 18th.

You must be logged in to post a comment.

Image of Zubenelgenubi 61

Zubenelgenubi 61

May 12, 2020 at 10:49 pm

Imagers should have a field day with SWAN. Can you imagine what modern imagers could have done with zero magnitude Hyakutake or Hale-Bopp in the 90's? I do remember some good fifth and sixth magnitude comets in binoculars and small telescopes, but I think most were higher in the sky than SWAN will be. Let's really, really hope for an outburst in about one week, that will last for two to three weeks, to get it up to third or fourth magnitude for visual observers.

You must be logged in to post a comment.

Image of loxiahall

loxiahall

May 13, 2020 at 5:24 am

From central Ontario, perfect conditions on May 12th and 13th at 4:30 a.m. EDT and still could not locate Swan in 15x70 binos. An outburst is needed to bring it out of the twilight. Amazing to think that this comet would have to brighten 11-12 magnitudes to equal the Great daylight Comet McNaught in Jan 2007 (witnessed it at noon...estimated it at -6!).

You must be logged in to post a comment.

Image of Rod

Rod

May 13, 2020 at 9:03 am

Bob King, I did view comet SWAN early this morning in MD. Clear sky and temperature 4C with light NW winds. I was out with binoculars and my 90-mm refractor telescope--Rod

[Observed 0400-0600 EDT. Sunrise 0556 EDT. The big event targets this morning was the Io shadow transit at Jupiter and 10x50 binocular observation of comet SWAN C/2020 F8. I could just barely see the comet in ENE sky from 0450-0500 EDT, close to 10 degrees altitude or elevation above the horizon. The comet ascended near 0403 EDT or 0803 UT. It had a short, small tail but faint because the horizon, brightening as sunrise approached near 0556 EDT. https://theskylive.com/ this morning shows observed magnitude +5.5 and estimated +7.0 for SWAN. Starry Night shows mv +6.22. Jupiter is putting on the show now in the telescope view. I enjoyed at 129x and 200x views using #58 Green filter and #12 Yellow filter, as well as no filters. Io tiny shadow started moving across the disk of Jupiter and distinct, easy to see near 0500 EDT or 0900 UT. Io shadow transit ingress this morning at 0853 UT or 0453 EDT. The three Galilean moons Ganymede, Callisto and Europa were in a tight triangle as Io shadow transit took place. Numerous cloud bands visible on Jupiter and size a bit more than 42"...This was a great morning out before sunrise and when I came back in, a large skunk was in the yard greeting me on the south side. I stopped and we just stared at each other for a bit, then the skunk scurried off to the woods by the horse barn. A very enjoyable way to greet the sunrise this morning with comet SWAN, Io shadow transit, Saturn, Mars, and waning gibbous Moon views using the telescope. Saturn began retrograde on 11-May-2020, Jupiter begins retrograde 14-May-2020.]

You must be logged in to post a comment.

Image of mary beth

mary beth

May 13, 2020 at 11:00 am

Great article Rod...Thanks for telling me!

You must be logged in to post a comment.

Image of Zubenelgenubi 61

Zubenelgenubi 61

May 14, 2020 at 9:17 am

Both in the morning and evening, the challenge will be to find just the right time to look at SWAN. In the morning as it rises higher, the sky gets brighter. In the evening, just the opposite. As you did, sometimes I have found that the right balance is later in twilight than you would think, but each situation is different. Same challenge as for young and old crescent moons. It is also affected by haze and that pesky small cloud bank near the horizon in just the wrong spot. It will be a fun challenge- maybe not the one most of us were hoping for, but still fun. For the general public, it may not be worth stressing SWAN at all, but possibly using Capella as the offset in the evening after about the 25th, assuming it can hang on at least at fifth or sixth magnitude.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 14, 2020 at 12:28 pm

Hi Zuben,
Yes, I agree with finding the right balance of twilight and night. Rather delicate, isn't it? I made sure to mention Capella (and Mirfak) to help the general public and experienced amateurs alike get a fix on the comet.

You must be logged in to post a comment.

Image of Bob King

Bob King

May 14, 2020 at 12:23 pm

Fantastic, Rod! Very happy to hear you saw it. You make me more eager than ever to spot it myself. Living further north I have to be patient.

You must be logged in to post a comment.

Image of SNH

SNH

May 18, 2020 at 6:51 am

Well, I last tried for the comet on the 9th and didn't want to wait this long to try again, but the weather didn't permit it. I was able to barely see the comet (F8 SWAN) in my 7x35 binoculars after spotting it with my 12x60s right at the beginning of astronomical twilight. It was basically a 15' wide glow with a good brightening towards the center. By comparing it to nearby stars, I'd have to say that it appeared about magnitude +7.5. I know that sounds faint (it surprised me), but even in high in a dark sky I don't see any way it could've been brighter than +7.0 factoring in more of its coma. But I'm no expert...I know that Bob was going to try for it this morning, and I'll be curious to hear if he saw it and what magnitude he'll put it at.

Scott

You must be logged in to post a comment.

Image of Bob King

Bob King

May 20, 2020 at 1:23 am

Hi Scott,
Thanks for writing in. I did indeed see it this morning at ~6 magnitude. You can read about it and see photos and fresh maps on my blog here: http://astrobob.areavoices.com/2020/05/19/my-morning-with-comet-swan/

You must be logged in to post a comment.

You must be logged in to post a comment.