SJAstro Page Index  |  Mercury 2020  |  Weather Links

Jupiter & Saturn Move Apart
December 27, 2020

 

The "Great Conjunction" of Jupiter and Saturn on December 21, 2020, has passed. On December 27, 2020, they were about 42 arc minutes apart, with Jupiter moving east (to the upper left in this view) at twice the rate of Saturn (13.5 vs. 6.7 arc minutes per day respectively) with respect to the background stars when they were observed from the Farm Stand in Moorestown, NJ. Seeing was poor and passing streaky clouds above the southwest horizon interfered, but the four Galilean satellites of Jupiter and Saturn's rings were still apparent visually with my Stellarvue 130 mm, f/7 apo refractor. However, the North and South Equatorial Belts of Jupiter were difficult to see on Jupiter's writhing surface. Both planets fit comfortably in the 1.5° field of a 13.5 mm, 100° SV eyepiece (67x), but the pairing was better seen with a 20 mm, 100° SV eyepiece (46x with a 2.2° field). Here's a tabulation of my conjunction sightings from December 12 through 29. Here's a photo comparison of the separation. The above image of them was captured at 5:35 pm, when Jupiter was a mere 10.3° altitude, using a Canon EOS RP mirrorless digital camera at the prime focus of the 130 mm, f/7 refractor (910 mm focal length) on an alt-azimuth mount. It's a single frame exposed 1/6 second at ISO 6400. It was cropped to 64% of the original linear dimensions for a field 1.5° wide x 1.0° high. At the time, the span of the Galilean satellites from easternmost Ganymede (upper left) to westernmost Callisto (bottom right) was 11 arc minutes. Mouseover for labels. The image of Saturn below is cropped from a separate single frame exposed 1/125 second at 5:35 pm, but otherwise the same parameters as the frame above. It's a 300 x 200 crop from the 6240 x 4160 original for a field 6.5 x 4.4 arc minutes. The higher shutter speed reduced overexposure and subdued some of the seeing turbulence, so instead of being just an oval blob, the ansae formed by the rings are now visible (albeit, this snapshot lacks any fine detail).

22° Solar Halo
December 23, 2020

While taking a walk on December 23, 2020, at Boundary Creek Park in Moorestown, NJ, I saw a nice 22° radius solar halo. This picture of it was taken at 2:58 pm EST with an iPhone 11.

Solstice Sunset,
Jupiter & Saturn Conjunction
East Point, December 21, 2020

The two largest planets of the solar system, Jupiter and Saturn, were at a close conjunction on December 21, 2020, which was also the day of the Winter Solstice (for the Northern Hemisphere). Poor weather prospects in my Maple Shade, NJ, home area prompted a trip to East Point, NJ, in an effort to find a clear sky towards the southwest. On arrival around 4 pm, it was gloomily overcast, but there was a brighter band of sky along the southwest sea horizon, so I didn't give up. Ultimately, the clouds rose away from the horizon and the Sun appeared. Here's a view of the Sun at 0.65° altitude over the Delaware Bay before it set at 4:41 pm EST. It's a single-frame, handheld snapshot taken at 4:35 pm with a Canon EOS RP mirrorless digital camera and a Canon 100 mm f/2.8 macro lens. It was exposed 1/1000 second at f/9, ISO 1600, and is uncropped for a field 20° wide x 14° high.

Some pesky broken clouds remained after sunset, but at 5:07 pm EST, I was able to spot Jupiter and Saturn in a gap between clouds using 8x42 binoculars, then at 5:10 pm, I was able to see both with unaided eyes. Saturn was considerably dimmer than Jupiter, magnitude +0.6 vs. -2.0 respectively, so it required a bit of concentration to see Saturn, whereas Jupiter was obvious. Observed with an 88 mm apo spotting scope starting at 5:17 pm (96x with a 49 arc minute field of view), there was more than ample space in the field of view around the planetary pair, which were just 6'14" apart. Both the North and South Equatorial Belts were evident on Jupiter's disc, and all four Galilean satellites were visible; from the east they were Callisto, Io and Ganymede. Europa was alone on the west. Visually, the ball of Saturn and it's rings were clearly visible, while Saturn's brightest satellite, Titan, was faintly visible. It was also quite evident that Saturn's surface brightness was much less than Jupiter's. I then swapped-out the spotting scope for the camera for a telephoto shot of the two planets. Clouds covered the planets again by 6 pm, and I had a brief final view of Jupiter (but not Saturn) as it glowed dimly through a thinner patch of clouds at 6:19 pm. At that point, even the 8x42s did not reveal Saturn, let alone any satellites. All the while, the first-quarter Moon shone brightly high above, and around 6 pm, it displayed a colorful corona as the overall cloud cover thickened. Nothing was visible in the sky when I left about 6:30 pm, and it was getting foggy along East Point Rd as I exited. This image was captured on December 21, 2020, at 5:32 pm EST with a Canon EOS RP mirrorless digital camera and a Canon  400 mm f/5.6 telephoto lens mounted on a fixed tripod with a gimbal head. It was exposed 0.5 seconds at f/5.6, ISO 1600. It's uncropped for a field 5.1° wide x 3.4° high. Jupiter is at the lower-left, Saturn is at the upper-right. Jupiter was about 14° altitude at the time.

This picture is from the same base image as the one above, but cropped to 16% of the original linear dimensions, to better show Jupiter's Galilean satellites. From the upper-left (east), they are Callisto, Io [Jupiter] and Europa. Ganymede is lost in the glare at the upper-left of Jupiter's blurred, overexposed disc. From end-to-end, the Galilean satellites spanned 5'58", nearly the same as the 6'14" separation between Jupiter and Saturn. Saturn's oval shape represents it's rings, which are not resolved from the ball here. In addition to the planets being considerably overexposed (to insure the Jovian satellites were recorded), the sky was becoming a bit hazy. In the days before and after the conjunction, both planets were in direct (or prograde) motion. Jupiter was moving eastward (to the upper-left in this view) with respect to the background stars at twice the rate of Saturn, hence it was catching up to, and then eventually passed Saturn. Specifically, for +/- one day from the conjunction on December 21, Jupiter was moving eastward at a rate of 13.2 arc minutes per day compared to 6.7 arc minutes per day for Saturn.

Jupiter catching up to Saturn
December 12, 2020

The two largest planets of the solar system, Jupiter and Saturn, will be in a close conjunction on December 21, 2020. This image of them was captured on December 12, 2020, from the baseball field complex in Maple Shade, NJ. It's a single-frame snapshot taken at 5:36 pm EST with a Canon EOS RP mirrorless digital camera and a Tamron 150 to 600 mm f/5.0 to 6.3 zoom lens, set to 600 mm focal length, mounted on a fixed tripod with a gimbal head. It was exposed 0.4 seconds at f/6.3, ISO 6400 and 4500K white balance, then mildly adjusted in Canon's Digital Photo Professional 4. It was cropped to 64% or the original linear dimensions for a field 2.2° wide x 1.5° high. Mouseover for labels. This was mainly a test shot, preparing for the days around conjunction and closest approach on December 21. It was the first evening of this approach when the separation of the two planets was less than one degree (slightly under 59 arc minutes at the time). On December 21 after sunset, the planets will be 6.2 arc minutes apart (center-to-center). For comparison, the span of Jupiter's Galilean moons in this image, from Ganymede at the upper left (east) to Callisto at the lower right (west), is 9.9 arc minutes. Note that the planet discs are rather overexposed, so their apparent diameters here are a bit bloated.

Algol at Minimum, Again
December 8, 2020

Another minimum of the eclipsing binary star, Algol (Beta Persei), was observed on the evening of December 8, 2020, around 7:30 pm EST from Swede Run in Moorestown, NJ. Without a moon in the sky, it was not too difficult a target for unaided eyes as were the minima on December 3 & 5 in a moonlit sky. Algol experiences a sharp, but brief dip in brightness from magnitude 2.1 to 3.4 with a 2.87 day period. Sky & Telescope online has a handy Minima of Algol calculator which indicated this minimum would be at 7:32 pm (SkyTools indicated 7:40 pm). This single-frame snapshot of Perseus was taken at 7:31 pm with a Canon EOS RP mirrorless digital camera mounted on a fixed tripod with a ball head and a Sigma 50 mm f/1.4 Art lens with a Hoya "diffuser" filter. It was exposed 4 seconds at f/2.5, ISO 1250, then mildly adjusted in Canon's Digital Photo Professional 4. The uncropped field is 39.5° wide x 27.0° high. Mouseover for labels; the numbers following the name/designation are the magnitudes (without the decimal point between the first and second numerals) obtained from SkyTools. The purpose of the diffuser is to enlarge the stars a little to better show brightness differences. Compare it the picture below that was taken without a diffuser where there's little difference in the apparent brightness of the stars. Even a little color difference is evident here (e.g., Gorgonea Tertia has a tinge of reddish color compared to Algol; correspondingly, the B-V values are 1.65 and -0.05 respectively). The diffuser also takes a toll on fainter objects; M34 is barely visible in this shot.

Algol at Minimum
December 5, 2020

The eclipsing binary star, Algol (Beta Persei), was observed near its minimum brightness on the evening of December 5, 2020, around 10:45 pm EST from Swede Run in Moorestown, NJ. It was a somewhat difficult target for unaided eyes because of suburban light pollution and the presence of a waning gibbous moon (70% illuminated) at about 12° altitude in the northeast. Algol experiences a sharp, but brief dip in brightness from magnitude 2.1 to 3.4 with a 2.87 day period. Sky & Telescope online has a handy Minima of Algol calculator which indicated this minimum would be at 10:43 pm (SkyTools indicated 10:51 pm). The S&T page also has some background information about Algol. This single-frame snapshot of the area around Algol was taken at 10:47 pm with a Canon EOS RP mirrorless digital camera and a Canon 100 mm f/2.8L macro lens mounted on a fixed tripod with a gimbal head (the gimbal arm can tilt at a 45° angle, allowing access to Algol's near-zenith position at the time). It was exposed 4 seconds at f/2.8, ISO 3200, then mildly adjusted in Canon's Digital Photo Professional 4. The uncropped field is 20.4° wide x 13.7° high. Mouseover for labels. Note: On December 12, I rotated this image 180° to nominally match the orientation with the image of December 8.

Asteroid (8) Flora & Comet C/2020 M3 (ATLAS)
November 9, 2020

The minor planet, informally an asteroid, (8) Flora was observed on the evening of November 9, 2020, from Carranza Field in Wharton State Forest, NJ, with 16x70 binoculars. It was not a difficult visual target in the constellation Cetus. Bob King has an online article at Sky & Telescope about Flora and Uranus, which are currently about 11° apart, with Uranus in the constellation Aries. This view of them was captured at 9:59 pm EST with a Canon EOS RP mirrorless digital camera and a Canon 200 mm f/2.8L lens on a fixed tripod. Exposed 4 seconds at f/2.8, ISO 6400, 3800K white balance, then no further adjustments. It was cropped to a 4:3 ratio for a field 6.9° wide x 5.2° high (roughly 70% of the original frame). Mouseover for labels.

While not seen visually with 16x70 binoculars, I took a snapshot in the direction of comet C/2020 M3 (ATLAS) on the evening of November 9, 2020, from Carranza Field in Wharton State Forest, NJ, at 10:06 pm EST. Taken with a Canon EOS RP mirrorless digital camera and a Canon 200 mm f/2.8L lens on a fixed tripod. Exposed 4 seconds at f/2.8, ISO 12,800, 3800K white balance, with some mild adjustment in Canon's Digital Photo professional 4, then cropped to a 4:3 ratio for a field 6.9° wide x 5.2° high (roughly 70% of the original frame). Mouseover for labels. I went back to Carranza on November 10 to try a visual sighting with my 88 mm apo spotting scope at a later hour so Orion would be higher in the sky. Using 25x, I picked it up at 11:30 pm EST without too much difficulty. When I got out my 15x56 binoculars about 15 minutes later, I was again able to spot it without too much difficulty. While still faint, the comet was certainly easier to see than it was at my initial sighting on October 22, 2020 (see the second image below). With both the scope and the binoculars, I checked my finder chart after making a sighting to reduce the possibility that my mind was filling-in the supposed object. The COBS database shows that C/2020 M3 (ATLAS) is currently a little brighter than magnitude 8, but its full diameter is reportedly close to that of the moon, so it has a low surface brightness.

Venus and Mercury
November 8, 2020

Venus and Mercury were 14° apart, both in the constellation Virgo, at 5:25 am EST on November 8, 2020, when this view of them was captured from Swede Run in Moorestown, NJ. Taken with a Canon EOS RP mirrorless digital camera and a Canon 100 mm f/2.8L macro lens on a fixed tripod. Exposed 2 seconds at f/2.8, ISO 1600, auto white balance with some slight adjustment in Canon's Digital Photo Professional 4. It's uncropped for a field 13.7° wide x 20.4° high. At the time, Mercury was about 4.3° altitude, Venus about 17° altitude. Mouseover for labels. On the morning of November 13, 2020, around 5:30 am EST for a nominal location of 40°N-75°W, these two planets will be about 13° apart with the 5% illuminated crescent moon about 6° above Mercury.

Comet C/2020 M3 (ATLAS)
October 22, 2020

A wisp of Comet C/2020 M3 (ATLAS) was captured in the image above on October 22, 2020. It was initially observed with 15x56 binoculars and an 88 mm apo spotting scope at 25x on the morning of October 18 at Carranza Field in Wharton State Forest, NJ, but I wanted to confirm the sighting of such a vague hazy patch, so I went back to Carranza, this time to the railroad crossing, on October 22. Despite frequently passing through fog on the way there, I continued to the RRX where it was relatively fog-free. I made a finder chart on the evening of October 21, but did not use it initially, I just recollected that it was a couple of degrees above (north of) the magnitude 3.2 star, Epsilon Leporis. After a brief scan with the 15x56s, I saw a vague patch of haze at 3:40 am EDT, the location of which then matched the comet's position as shown on my SkyTools finder chart. The COBS database indicates it is approaching eight magnitude now. The image above is a single frame captured at 3:58 am with a Canon EOS RP mirrorless digital camera and a Canon 200 mm f/2.8L lens on a fixed tripod. It was exposed 4 seconds at f/2.8, ISO 12,800, with white balance set to 3800K. It was mildly adjusted in Canon's Digital Photo Professional 4, then cropped to about 60% of the original frame (and a 4:3 ratio) for field 5.9° high x 4.5° wide. Mouseover for labels. The image below is a further crop, to a field 1.2° wide x 1.6° high, of the previous image to better show the faint haze of the comet's coma. Mouseover for label.

Young Crescent Moon
October 17, 2020

New Moon was on October 16, 2020, at 3:31 pm EDT, so on October 17, 2020, the Moon was roughly 27 hours old after sunset at 6:17 pm for this location, Swede Run in Moorestown, NJ. I was able to spot the thin crescent, 1.9% illuminated, at 6:25 pm with 15x56 binoculars when it was at 7.3° altitude in the WSW. I subsequently saw the crescent with unaided eyes at 6:44 pm, although I might have seen it sooner if I wasn't preoccupied with my camera in the interim. The picture above was captured at 6:45 pm (3.9° altitude) using a Canon EOS RP mirrorless digital camera with a Canon 400 mm f/5.6L telephoto lens, on  a fixed tripod, providing an uncropped field 5.1° wide x 3.4° high. It was exposed 1/125 second at f/5.6, ISO 1600 using automatic white balance. Besides size reduction for this web page, no processing was applied.

Looking South towards Wallops Island, VA
from North Cape May, NJ
October 1, 2020

I travelled to Cape May, NJ, on October 1, 2020, with the hope of seeing the Antares rocket launch from Wallops Island, VA, carrying the Cygnus cargo freighter to the International Space Station. It was scheduled for 9:38 pm EDT, so I figured in the meantime, I would take a crack at spotting Mercury after sunset, so I went to North Cape May for a view to the west over the Delaware Bay. The spot was about half a mile north of the Cape May Canal and the NJ terminus of the Cape May-Lewes Ferry. This picture, taken with an iPhone 11, looks south about 7 pm and shows the cloud cover moving in. These clouds precluded spotting Mercury, and ultimately, the Antares launch, which was fortunately (for me) scrubbed by a technical problem a couple of minutes before the scheduled ignition. However, the weather was ideal for the rescheduled launch at 9:16 pm on October 2. This time, I observed from Swede Run in Moorestown, NJ, which is about 152 miles from the launch pad at Wallops, vs. 83 miles for Cape May. Nevertheless, we had a fine view of a bright orange dot rising from the tree line in the SSW, which was a spectacular plume in 15x56 binoculars. It followed an arc to the left, crossing the meridian and reaching a maximum altitude of about 20° before the orange rocket exhaust extinguished for a minute or so as it coasted between the first and second stages. It reappeared as a bright white dot that started to arc downwards and vanish behind the trees in the SE. Of course, the descent was a matter of perspective since the rocket was still gaining altitude vs. the earth's spheroidal surface as it headed in the direction of Africa. On the evening of October 3, around 7:45 pm, I was able to spot the now-orbiting Cygnus cargo spacecraft as it trailed the ISS by about 2¼ minutes. I used my 15x56 binoculars mounted on a tripod, spotted the ISS, locked the position and waited for the Cygnus to cross the same field. While considerably dimmer than the ISS, the Cygnus was still bright enough (around magnitude +2, roughly the same as Polaris), that it should have been visible to unaided eyes had I known better where to look for it. Weather permitting, I hope to give it another try on the evening of October 4. It should be closer to the ISS as it is scheduled to dock on October 5. Alas, the weather did not allow a sighting on October 4.

Click here for the previous page.

Click here for an index to previous SJAstro pages.