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Nova Herculis 2021 (V1694 Her)
June 18, 2021

Alerted by a Bob King article at Sky & Telescope online, I observed Nova Herculis 2021 (V1694 Her) from the NJ Pines at the first opportunity on June 16, 2021, then again on June 18, 2021, when I took this snapshot. It was discovered at magnitude 8.4, brightened to magnitude 6.4, then faded, hence I was anxious to catch it before it was too late (especially since I'm largely limited to using my 88 mm spotting scope now). Using the 88 mm at its maximum 60x, on both June 16 and 18, I thought Nova Her was comparable in brightness to a nearby magnitude 10 star. This snapshot was captured on June 18 at 1:44 am EDT with a Canon EOS RP mirrorless digital camera and a Canon 200 mm, f/2.8L telephoto lens on a fixed tripod. It's a single raw frame exposed 2 seconds at f/2.8, ISO 8000, 4200K white balance. Unprocessed, but cropped to 38% of its original linear dimensions for a field 4.0 wide x 2.6 high. Mouseover for labels.

 

 

Barnard's Star
June 18, 2021

I been following Barnard's Star (V2500 Oph) for some years now, and usually take at least a quick look at it when it's in season and I'm out observing. I also take a snapshot periodically and here's one I took on June 18, 2021, from the NJ Pines. The last snapshot I took was on March 12, 2019 (scroll to the bottom of that page) and before that, on May 21, 2017. Barnard's Star has the greatest known proper motion, about 10.3 arc seconds per year compared to the background sky, which is roughly a Jupiter diameter every four years. This image was captured at 1:39 am EDT with a Canon EOS RP mirrorless digital camera and a Canon 200 mm, f/2.8L telephoto lens on a fixed tripod. It's a single raw frame exposed 2 seconds at f/2.8, ISO 8000, 4200K white balance. Unprocessed, but cropped to 87% of its original linear dimensions for a field 8.9 wide x 5.9 high. Mouseover for labels. The image below is a further crop for greater enlargement.

Proper motion detected...

This is the same raw frame as the image above from June 18, 2021, but cropped to 29% of its original linear dimensions for a field 3.0 wide x 2.0 high. Mouseover for labels. While observing Barnard's Star visually with the 88 mm spotting scope on June 18, I felt that the spacing between it and TYC 00425 0262 1 had increased compared to previous years, but that's very subjective and qualitative. So, I decided to measure this image and the one I took in mid-May 2017, which would be an approximate four-year time span (actually 49 months), to see if there was any apparent change that would be indicative of proper motion.

I tried on-screen measurements of the spacing between the TYC star and Barnard's Star, but it was too clumsy to get reliable values, so I made a negative of each image, enlarged it and measured paper printouts, ultimately with a Pickett 150 mm metal ruler. I used SkyTools to measure the angular span between TYC 00425 0262 1 and HD 163697, the left point of the asterism outlined on mouseover in the above image (it was 811 arc seconds). The resulting plate scale on those two prints was: 2017 = 64 mm = 12.67"/mm; 2021 = 49 mm = 16.55"/mm.

Next, I measured the span from the TYC star to Barnard's Star: 12.5 mm in 2017 = 158.4", 12 mm in 2021 = 198.6" (a difference of 40.2"). However, the lines from the TYC star to the positions of Barnard's Star on the two dates were not superimposed but diverged at a 4.8 angle. Correcting for that with some basic trigonometry, I calculated the distance between Barnard's Star on the two dates was 42.87", or 10.50"/year, which is pretty close to the Hipparcos astrometric spacecraft's proper motion value of 10.36"/year. I also calculated the spans between the respective stars in the images based their x,y pixel positions as shown by Corel PaintShop Pro 2021. That yielded a proper motion of 39.78" or 9.74"/year. I haven't figured out why the two measurement techniques yielded moderately different results, but they averaged 10.12"/year. Updated on June 28, hopefully for the last time, after building and using a spreadsheet to do the calculations without any intermediate rounding.

 

 

Comet C/2020 T2 (Palomar)
June 18, 2021

The comet C/2020 T2 (Palomar) had been on my observing back burner because it's been around magnitude 10, which would be tough for my little 88 mm apo spotting scope. However, on the evening of June 17, 2021, Ray Maher of the South Jersey Astronomy Club (my fellow "comet nut") posted that he had seen it with his 12.5-inch Newtonian. Encouraged by his observation, I added it to my short target list for my trip to the Pines later that night. Moonset would be at 1:30 am EDT on June 18, so I didn't arrive until about 12:45 am. I first looked for the comet about 1 am, but was unsuccessful, perhaps because the one-third illuminated moon was still up and not that far from the comet near Arcturus. I looked again around 2 am, after moonset, but the comet was now lower in the northwest and into the Philadelphia light dome, and again I didn't see it.

While I had the camera set up in the interim between initial and final visual observing, I took some snapshots of the comet area, hoping something would show up even if I didn't see anything visually. This image was captured on June 18, 2021, at 1:29 am EDT with a Canon EOS RP mirrorless digital camera and a Canon 200 mm, f/2.8L telephoto lens on a fixed tripod. It's a single raw frame exposed 2 seconds at f/2.8, ISO 12,800, 4200K white balance. It was mildly adjusted in Canon's Digital Photo Professional 4 and cropped to 24% of its original linear dimensions for a field 2.5 wide x 1.7 high. Mouseover for labels.

There is a very faint spot of haze at the labeled position on the image. However, while there are a few other similar hazy spots on the image, this one is right at the spot corresponding to the comet's position on a SkyTools chart for the respective date and time.

 

 

Partial Solar Eclipse
June 10, 2021

There was an annular eclipse of the sun on June 10, 2021, but it was only a partial eclipse as viewed from the Delaware Valley. This image was captured from Laurel Run Park in Delran, NJ, at 5:51:37 am EDT (sun at 302′ altitude) with a Canon EOS RP mirrorless digital camera and an unfiltered Tamron 150 to 600 mm f/5.0 to 6.3 zoom lens (on a fixed tripod) set to 600 mm focal length. It was automatically exposed (minus 3 stops) for 1/4000 second at f/22, ISO 100 and daylight white balance. Cropped to 58% of its original linear dimensions for a field 2.0 wide x 1.3 high, but otherwise unprocessed. Click here for more eclipse pictures.

 

 

(4) Vesta passes M65 & M66
June, 2021

The minor planet (or asteroid), (4) Vesta is wrapping up it's current 2021 apparition with a close pass of the well-known galaxy trio beneath Leo's hindquarters, M65, M66 and NGC 3628. In particular, it will pass less than half a degree south of M65 and M66 on June 10 and 11 respectively, as shown by the track on the accompanying annotated SkyTools chart. Vesta is now in the high magnitude 7.x range, but still a binocular object in clear suburban skies. Click the chart for a larger version, or click here for a larger negative version, suitable for printing. For scale, the stars Iota Leo and Chertan are about 5.4 apart, while the 14-day track of Vesta is about 4.4 long (an average of one-third degree per day).

Update: I was out to the Pines on the evening of June 15, 2021, after a spell of bad weather for a last chance to see Vesta near M66. Using my 88 mm apo spotting scope at 25x, I spotted Vesta at 11:12 pm, but it was only about 25 altitude in the west, towards the Philadelphia light dome. As a result, I could not see M66 or either of the other two galaxies in the trio, and with the widening spacing spacing from the galaxies, the dropping altitude after sunset and an increasing moon, the chance to see Vesta and the galaxies together has passed. Vesta was sighted on June 24 at 11:45 pm with 15x56 binoculars from Swede Run in Moorestown, NJ. This sighting of Vesta marks the 44th occasion I've seen it since February 16, 2021, and may well be the last time for this apparition.

 

 

The Lunar X and V
May 18, 2021

The thick crescent Moon was observed around sunset on May 18, 2021, from the baseball field complex in Maple Shade, NJ. The main reason for looking at it, and taking this picture, was to capture the "Lunar X," an illumination feature that appears when the rays of lunar sunrise catch the walls of the craters Purbach, La Caille and Blanchinus (more about the X). Concurrently, a separate V-shaped illumination feature appears too.

This is a single frame taken at 8:12 pm EDT (the same time as sunset) in a still-bright sky using a Canon EOS RP mirrorless digital camera and a Tamron 150 to 600 mm f/5 to 6.3 telephoto zoom lens (set to 600 mm focal length) on a fixed tripod with a gimbal head (here's an iPhone picture of the setup). It was exposed 1/1000 second at f/8.0, ISO 4000, daylight white balance, then mildly adjusted in Canon's Digital Photo Professional 4 and cropped to 29% of the width x 32% of the height (a 4:3 ratio) which yielded a field 1.0 wide x 0.75 high. Mouseover for labels.

At the time, the 42% illuminated Moon in Leo was at 62 altitude in the southwest. It was 7.2 days old (after new) and 19 hr before first quarter on May 19 at 3:13 pm. The "X" occurs at an typical 358 lunar colongitude, which WinJUPOS (download page) indicated would occur at 7:45 pm (Dave Mitsky's DVAA monthly calendar predicted 23:41 UT, which equals 7:41 pm EDT). When I arrived at the baseball field complex and first looked at the Moon with my 88 mm apo spotting scope at 7:41 pm using the 25 to 60x zoom eyepiece at 25x, the "X" was plainly visible, but it was even better at 60x. I continued watching it on the camera's viewing screen (live view at 600 mm & 10x) through my last shot at 8:12 pm, the picture above. Here's my Lunar X page.

I've created a page with Lunar X predictions for our area (nominally 40N-75W) on July 16, 2021. The referenced Dave Mitsky prediction is from his monthly calendar linked at the DVAA web site. Phil Harrington's predictions for 2018 to 2023 are tabulated here.

 

 

Venus and the Young Crescent Moon
May 12, 2021

The very young crescent Moon joined the inner planet Venus on the evening of May 12, 2021, as shown in this snapshot from Swede Run in Moorestown, NJ. This is a single frame taken at 8:41 pm EDT with a Canon EOS RP mirrorless digital camera and a Canon 400 mm f/5.6L telephoto lens on a fixed tripod. It was exposed 1/320 second at f/5.6, ISO 12,800 and daylight white balance. It's direct from the camera except for size reduction, removal of a small blemish and exposure reduction by half a stop. It's uncropped for a field 5.1 wide x 3.4 high. Mouseover for labels.

At the time, Venus was 4.2 altitude and the Moon 3.9 altitude. The Moon was 1.24 days old (29 hr 41 min since New Moon on May 11 at 3:00 pm EDT), and it was 1.2% illuminated. The Moon and Venus were 1.1 apart, center-to-center. The birds flying along the treetops appear to be the ubiquitous Canada Geese.

Sunset was at 8:06 pm EDT. Venus and the sublimely thin crescent moon were initially sighted with 8x42 binoculars at 8:15 pm, then Venus was spotted immediately afterwards with unaided eyes. The lunar crescent was first seen with unaided eyes at 8:28 pm, while the background twilight was still fairly bright. The other inner planet, Mercury, was a little more than 9 above Venus and the Moon. It was first sighted at 8:24 pm with the 8x42s, then unaided eyes at 8:34 pm. Magnitude -3.9 Venus was about 36x brighter than magnitude 0.0 Mercury.

 

 

Nova Cassiopeiae 2021 - Outburst
May 12, 2021

Nova Cassiopeiae 2021 (V1405 Cas) experienced a sudden increase in brightness on May 6-7, 2021, as detailed by Bob King in this S&T online article. On the morning of May 11, I was able to observe it in a suburban sky through passing cirrus clouds with 15x56 binoculars (my casual magnitude estimate was 5.4). On the morning of May 12, 2021, I went to the relatively dark NJ Pines to attempt seeing it with unaided eyes. I was there from about 3:30 until 4:15 am (astronomical twilight began at 3:58 am) and passing cirrus clouds were again present, but this time, there were large gaps between the moving clouds. Using 8x42 binoculars, Nova Cas (estimated magnitude 5.6) was easy to see (as was nearby M52). I think I might have glimpsed the nova a couple of times with unaided eyes using averted vision, but they weren't certain sightings by any means.

The image above is a single raw frame captured at 3:52 am EDT using a Canon EOS RP mirrorless digital camera with a Canon 200 mm f/2.8L lens on a fixed tripod. It was exposed 2.5 seconds at f/3.2, ISO 6400. It was slightly adjusted with Canon's Digital Photo Professional 4, including cropping to about 48% of the original width and height, resulting in a field about 4.9 wide x 3.3 high. Mouseover for labels. The numbers after the star designations are the magnitudes (sans decimal point). Those in yellow are from AAVSO Chart X26520GZ, those in gray are from SkyTools. Here's an image of Nova Cas 2021 that I took on April 21, 2021.

From the mid-5 magnitude range noted above, Nova Cas continued to drop noticeably in brightness. My casual magnitude estimates were 5.9 on May 14 (at home, 15x56), 6.6 on May 15 (Swede Run, 15x56) and 7.2 on May 18 (Pines, 15x56 & 88 mm spotting scope). Update: I went to Swede Run on June 1 at 1:15 am, June 4 at 10:34 pm, June 5 at 11:30 pm and June 7 at 3:15 am; in each case using 15x56 binoculars on a monopod, I estimated Nova Cas as about magnitude 6.8. On June 10 at Carranza, using my 88 mm apo spotting scope, I estimated magnitude 6.9. As on June 11 around noon, the AAVSO visual light curve seems to have flattened at about magnitude 7 (for now). N.B., don't bet the ranch on my magnitude estimates!

Nova Cas was observed again from the Barnegat Road Observing Site in the NJ Pines on July 23, 2021, using a 130 mm apo refractor with a 20 mm, 100 eyepiece (= 46x, 2.2 TFOV). With that. I could easily see the Nova and stars HD 220819, mag 6.6, and HD 220057, mag 6.9, all at the same time. The nova appeared to be between them in brightness, which is consistent with the updated light curve shown below. The nova also displayed a mild reddish color.

I've been observing Nova Cas casually every time I'm out to the Pines since then. On October 2, 2021, at the Barnegat Site, I took the time to do an actual estimate using my 88 mm apo spotting scope at 25x; it was magnitude 7.8. Contemporaneous estimates at AAVSO averaged about magnitude 7.7.

This is a screen clip of the light curve generated from AAVSO data for Nova Cas through July 26 and represents visual and visual equivalent photometric magnitude estimates. Click here to see the current light curve including all wavelengths.

 

 

 

Venus and Mercury
April 26, 2021

The sky was quite clear on the evening of April 26, 2021, so I went to Carranza Field in Wharton State Forest, NJ, to spot Venus and Mercury around sunset at 7:48 pm EDT. They were in conjunction on this date at 5 am, about 1.3 apart. By sunset, that spacing had increased to about 1.6 as rapid Mercury moved eastward past Venus (nominally upwards in this view).

Magnitude -3.9 Venus was initially spotted at 7:38 pm with 15x56 binoculars (stabilized on a monopod) when it was at 8.6 altitude and lost to the treetops at 8:08 pm, 3.2 altitude. Magnitude -1.5 Mercury was initially spotted with the 15x56s at 7:45 pm when it was at 8.7 altitude and lost to the treetops at 8:15 pm, 3.3 altitude. They were also seen with 8x42 binoculars, but with either pair of binoculars, they were somewhat difficult to see, especially with the 8x42s, because of minimal contrast against the relatively bright twilight background. Neither planet was seen with unaided eyes. This is the fourth sighting of Venus for this elongation and the second for Mercury. The first for Venus was in the daytime, at 4:02 pm on April 13 and the second was just after sunset on April 19. Both Venus and Mercury were sighted around sunset on April 23 and 26, in each case with 15x56 binoculars and several instances with 8x42 binoculars. Venus may have been glimpsed with unaided eyes on April 23.

The image above is a single raw frame taken at 8:07 pm using a Canon EOS RP mirrorless digital camera with a Tamron 150 to 600 mm f/5.0 to 6.3 zoom lens on a fixed tripod, set to 600 mm focal length. It was automatically exposed 1/1000 second at f/6.3, ISO 6400, then mildly adjusted with Canon's Digital Photo professional 4, including cropping to 80% of the original dimensions, resulting in a field about 2.75 wide x 1.84 high. Mouseover for labels.

 

 

Comet C/2020 R4 (ATLAS)
April 21, 2021

Since it was clear on the morning of April 21, 2021, I went to Wharton State Forest, NJ, to catch the last moon-free hour before full moon on April 26. The moon, a day past first quarter, set at 3:24 am EDT and astronomical twilight would begin at 4:33 am. I arrived at 2:50 am and the sky was cloud free with satisfactory transparency. The temperature was pleasant at 49F with no wind. When I left at 4:15 am, it was 47F.

I first attempted to sight Comet C/2020 R4 (ATLAS) at 3:10 am with 15x56 binoculars. I think I spotted a small, faint patch of haze in the expected position between Sarin (Delta Her) and Kornephoros (Beta Her), which are south of the Hercules Keystone. I then looked with my 88 mm apo spotting scope at 25 to 60x and was fairly certain I that I did see a patch of faint haze at 3:15 am. This was a follow-up to my initial sighting of the comet on April 8 with my 130 mm apo refractor, with which it was just a faint glow too. Here's some data at COBS.

The image above shows the comet as a distinct hazy patch at the respective location. It's from a single raw frame taken at 3:23 am using a Canon EOS RP mirrorless digital camera with a Canon 200 mm f/2.8L lens on a fixed tripod. It was exposed 4 seconds at f/2.8, ISO 8000. Some adjustments were made in Canon's Digital Photo professional 4, including cropping to a 4:3 ratio, using about 64% of the original width x 72% of the height, resulting in a field about 6.6 wide x 5.0 high. Mouseover for labels.

Martin Mobberley captured this view about three hours later, remotely from New Mexico. During the interval, the comet moved about 33 arc minutes to the northwest, a rate of 4.4 per day. The rapid apparent motion reflects the comet being at its closest approach to earth (0.46 au away) on or around April 23, 2021.

 

 

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Last Update: Tuesday, October 05, 2021 at 01:03 PM Eastern Time