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Nova Cassiopeiae 2021
April 21, 2021

Also on the morning of April 21, 2021, while at Wharton State Forest, I checked several novae that were recently discovered when they were around eighth magnitude. They were Nova Cas 2021 (V1405 Cas), Nova Sgr 2021 (V6595 Sgr) and Nova Sco 2021 No. 2 (V1710 Sco). I had already seen Nova Cas several times from different locations using different optics, one of which is covered further down this page. This morning, April 21, it wasn't difficult to see Nova Cas and split the nova from a close ninth magnitude star using 15x56 binoculars and later, the 88 mm apo spotting scope. It appeared distinctly brighter than that star just as it did the first time I saw it. In between, it seemed to have faded such that I saw little or no difference in brightness between them. Correspondingly, the visual light curve at AAVSO shows this nova starting in the magnitude 7.5 to 8 range, then dropping to the 8 to 8.5 range, and now brightening to the 7.5 to 8 range again.

The image above includes Nova Cas and is a single raw frame captured at 3:47 am EDT on April 21 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/2.8, 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.

 

 

Nova Sagittarii 2021 No. 2
April 21, 2021

Additionally on the morning of April 21, 2021, at Wharton State Forest, I looked for Nova Sgr 2021 No. 2 (V6595 Sgr). I had seen Nova Sgr from the Pines on April 8 with my 15x56 binoculars and 130 mm apo refractor. It was just a bit brighter than an adjoining ninth magnitude star (forming a "double star" much like Nova Cas). This morning, April 21, I could not find it with the 15x56s or the 88 mm spotting scope, suggesting there had been significant fading since April 8. Correspondingly, the visual light curve at AAVSO shows this nova starting around visual magnitude 8, but dropping to 11+ on April 21, which would explain my inability to see it then. Not only is it dim, but there would be significant atmospheric extinction at the low altitude in Sagittarius.

However, it may be present in the image above, which includes the Nova Sgr area. Its a single raw frame captured at 3:35 am EDT on April 21 using a Canon EOS RP mirrorless digital camera with a Canon 200 mm f/2.8L lens on a fixed tripod. It was exposed 3.2 seconds at f/2.8, ISO 6400. It was slightly adjusted with Canon's Digital Photo professional 4, and cropped 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.

The image below was a further cropped to enlarge the nova area of the same frame, to 29% of the original width x 32% of the original height for a field 3.0° x 2.2°. It does show a fleck of light that might be the dimmed nova. Mouseover for labels.

 

 

Novae Scorpii 2021
April 21, 2021

Finally on the morning of April 21, 2021, at Wharton State Forest, I looked for Nova Sco 2021 (V1710 Sco). I had not seen Nova Sco before and I could not find it with the 15x56s or the 88 mm spotting scope, suggesting there had been significant fading since it was discovered around magnitude 8. Correspondingly, the visual light curve at AAVSO shows this nova dropping to magnitude 11+ by April 21, which would explain my inability to see it. Besides being dim, there would also be significant atmospheric extinction at the low altitude in Scorpius where it was barely above the treetops.

However, it may be present in the image above, which includes the Nova Sco area. Its a single raw frame captured at 3:35 am EDT on April 21 using a Canon EOS RP mirrorless digital camera with a Canon 200 mm f/2.8L lens on a fixed tripod. It was exposed 3.2 seconds at f/2.8, ISO 6400. It was slightly adjusted with Canon's Digital Photo professional 4, and uncropped for a field about 10.3° wide x 6.9° high. Mouseover for labels.

The image below was cropped to enlarge the nova area of the same frame, to 32% of the original width x 36% of the original height for a field 3.3° x 2.5°. It does show a fleck of light that might be the dimmed nova. Mouseover for labels.

 

 

 

Finding Messier 51
March 22, 2021

This image was captured on March 22, 2021, from Wharton State Forest, NJ. It shows the galaxy pair M51, consisting of NGC 5194 (The Whirlpool Galaxy) and its companion, NGC 5195, sometimes referred to as M51A and M51B respectively. Messier himself quaintly referred to them as "two atmospheres," so he did recognize this object as a pair. It is labeled (on mouseover) to show an easy way of finding it visually, with binoculars or a scope by starting at Alkaid, the star at the end of the Big Dipper's handle.

This snapshot was taken at 9:40 pm 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 2.5 seconds at f/2.8, ISO 6400 and 4000 K white balance. It was mildly adjusted in Canon's Digital Photo Professional 4 and cropped to 75% of the original linear dimensions for a field 7.7° wide x 5.2° high. At the time, there was a 64% illuminated moon at 69.5° altitude in Gemini, so the sky was somewhat bright, which limited exposure. Nevertheless, the two lobes can be seen on careful inspection, brighter NGC 5194 is on the right and dimmer NGC 5195 is on the left.

 

 

Nova Cassiopeiae 2021
March 22, 2021

Nova Cassiopeiae 2021, now formally designated V1405 Cassiopeiae, was discovered on March 18, 2021, as reported in this Sky & Telescope online article. Currently around eighth magnitude, it's a relatively easy target for visual observers using a small scope or binoculars, with the caveat that this circumpolar object (for 40°N latitude) is reaching lower culmination on March nights. Here's a SkyTools chart. Update: Here's a AAVSO visual light curve generated on April 2, 2021.

This image, which includes the nova, was captured on March 22, 2021, from Wharton State Forest, NJ. V1405 Cas is about 6° west-northwest of Caph (Beta Cas), the second magnitude star at the western end of Cassiopeia's W-shaped stick figure. This snapshot of the area was taken at 9:14 pm 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 3200 and 4000 K white balance. It was mildly adjusted in Canon's Digital Photo Professional 4 and cropped to 40% of the original linear dimensions for a field 4.1° wide x 2.7° high. Mouseover for labels. At the time, the nova was at 18° altitude in the north-northwest, so it was within the Philadelphia light dome. In addition, there was a 64% illuminated moon at 71° altitude in Gemini, so the sky was relatively bright, which limited exposure. Nevertheless, all seven stars of the Little Dipper were visible with unaided eyes (albeit, the five fainter stars required some effort to see). The weather was relatively pleasant, 42°F with no wind.

 

 

(4) Vesta in Leo
March 22, 2021

This image of the asteroid (4) Vesta was captured on March 22, 2021, from Wharton State Forest, NJ. Vesta is now just west of Leo's hindquarters and is in retrograde motion heading west. It will be stationary in mid-April 2021, then resume direct eastward motion. This snapshot was taken at 9:37 pm 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 2.5 seconds at f/2.8, ISO 3200 and 4000 K white balance. It was not adjusted and is uncropped for a field 10.3° wide x 6.9° high. Mouseover for labels. At the time, Vesta was about 53° altitude with a 64% illuminated moon in 51° away in Gemini Vesta recently passed through the two sixth magnitude HD stars, which provided an excellent reference for the asteroid's movement.

 

 

Mercury and Jupiter Conjunction
March 5, 2021

The planets Mercury and Jupiter were just 21 arc minutes apart as they cleared the treetops on March 5, 2021, as viewed from Swede Run in Moorestown, NJ. Conjunction in geocentric right ascension occurred at 2 am EST, astronomical twilight started at 4:57 am and sunrise would be at 6:27 am. This snapshot of them was taken at 5:39 am 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 1/60 second at f/2.8, ISO 12,800 and 4000 K white balance. It was slightly adjusted in Canon's Digital Photo Professional 4 and cropped to a field 9.6° wide x 5.4° high. Mouseover for labels. At the time, they were about 3° altitude in the east-southeast. Mercury was magnitude +0.2 and Jupiter was -2.0, so Jupiter was almost 8x brighter. Both were visible with unaided eyes, although with some difficulty in the brightening twilight. The sky was clear with a third-quarter moon present. It was chilly, 27°F with a stiff breeze.

 

 

(4) Vesta near Opposition
March 2, 2021

The minor planet, or asteroid, (4) Vesta will reach solar opposition on March 4, 2021, at 1:08 pm EST. Vesta is not the largest asteroid, but it's the brightest. At magnitude 6.0 to 6.2 now (depending on the data source), those with keen eyes might be able to spot it without optical aid from a dark site, but for the rest of us, it's an easy binocular target in the hindquarters of Leo the Lion. Here's a finder chart for March 8 through April 1, 2021. At the beginning of that period, Vesta is moving about 15 arc minutes per day (a quarter of a degree, or nominally half a moon diameter) with respect to the background stars. By April 1, it will have slowed to about 9 arc minutes per day as it nears the end of its retrograde loop. Bob King posted an online article at Sky & Telescope about observing Vesta in March 2021; the article includes a finder chart (with tick marks at 0 hr UT) that extends into June 2021 when Vesta passes close to the galaxies M65 & M66.

This snapshot including Vesta was taken from Wharton State Forest, NJ, on March 2, 2021, at 9:06 pm EST 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 4 seconds at f/2.8, ISO 6400 and 4000 K white balance. It was slightly adjusted in Canon's Digital Photo Professional 4 and cropped to 58% of the linear original dimensions to better show the trio of galaxies, M65, 66 & NGC 3628. The resultant field is 5.9° wide x 4.0° high. Mouseover for labels.

At Carranza on Monday, March 1, Vesta and M66 were seen simultaneously with 15x56 binoculars around 8:15 pm; at the time, they were 2.8° apart. On March 2, around 9:30 pm, I also observed Vesta with my 88 mm apo spotting scope at 25 to 60x. Notably, it showed a mild yellowish color, which is vaguely apparent in the image. I saw Vesta again on the morning of March 3, at 5:50 am with 8x42 binoculars while I was out to observe Mercury, Jupiter and Saturn before sunrise.

 

 

Jupiter, Mercury & Saturn
January 10, 2021

Jupiter, Mercury and Saturn formed a compact, nearly equilateral triangle on January 10, 2021. As seen here from Swede Run in Moorestown, NJ, the triangle was roughly 2° on each side with bright Jupiter (magnitude -2.0) at the upper vertex, 4.0° altitude. Moderately bright Mercury (magnitude -0.9) was at the lower-left vertex, 2.4° altitude, and dimmer Saturn (magnitude +0.6) was at the lower-right vertex, 2.1° altitude. Mouseover for labels.

This snapshot of them was captured at 5:37 pm EST with a Canon EOS RP mirrorless digital camera and a Canon 200 mm f/2.8L telephoto lens on a fixed tripod. It was exposed 1/50 second at f/2.8, ISO 1600, then mildly adjusted in Canon's Digital Photo Professional 4 and cropped to 64% of the original linear dimensions for a field 6.6° wide x 4.4° high.

In a clear sky, they were also observed visually. Jupiter and Mercury were initially spotted with 8x42 binoculars at 5:19 pm, then Jupiter was first seen with unaided eyes at 5:22 pm. Saturn was first seen in the 8x42s at 5:26 pm and Mercury was first glimpsed with unaided eyes at 5:35 pm. Saturn was never seen with unaided eyes and its visibility was poor even with the binoculars, comparable to its feeble appearance in the picture.

 

 

 

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Last Update: Friday, May 14, 2021 at 11:23 AM Eastern Time