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Comet C/2019 Y4 (ATLAS)
March 27, 2020

I finally spotted Comet C/2019 Y4 (ATLAS) at 8:55 pm EDT on March 27, 2020, with 15x56 binoculars (then subsequently with 16x70 binoculars and an 88 mm apo spotting scope) from the New Jersey Pines. The degree-long triangle formed by Rho, Sigmač and SigmaČ Ursae Majoris was a handy unaided-eye reference for locating the comet about 3.7° west of Rho. The image above was captured at 9:29 pm 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 3.2 seconds at f/3.2, ISO 10,000. The image was cropped to 58% of the original size for a field 5.9° wide x 4.0° high. The original raw frame was set to 3600K white balance then cropped and converted to a JPEG in Canon's Digital Photo Professional. Mouseover for labels.

Observing was somewhat hampered by the persistent passing of cirrus clouds, and the transparency wasn't ideal in between clouds. As a result, the observed comet was just a dim patch of haze (not greatly unlike its appearance in these snapshots). Magnitude estimates for C/2019 Y4 were concurrently around 8, and it may become visible with unaided eyes in May 2020, but keep in mind that comet brightness predictions are usually fraught with uncertainties. Indeed, by early April 2020, it became apparent that the steep upward slope of the brightness curve had flattened out, and not long afterwards, started heading down, while images of the comet started showing fragment shedding. It may or may not be disintegrating, but it now seems very unlikely this comet will become spectacular as many hoped, and it probably won't even reach naked-eye brightness.

 

This image is the same raw frame as above, but cropped to 29% of the original linear size for a field 3.0° wide x 2.0° high. Mouseover for labels.

 

 Finally, a severe crop, about 5% of the linear dimensions of the original raw image, then rotated 90° counterclockwise. This was done to approximately match an image of Y4 at another message board, primarily with regard to the multiple star at the 8 o'clock position from the comet. That star is HD 69804 or SAO 14520. The trio is STF 1208A, B & C. Per SkyTools, A+B are magnitude 8.43+13.6, 9.6" separation and 146° PA, while A+C are magnitude 8.43+10.8, 19.9" separation and 336° PA. In this view, C can be seen as a distinct bump at the bottom-right of A, and B is perhaps a slight bulge at the upper-left of A. I believe I saw A & C in the 88 mm spotting scope, but I should have paid closer attention to them.

 

 

 

Jupiter, Mars and the Crescent Moon
March 18, 2020

The waxing Crescent Moon (with earthshine, so the crescent is greatly overexposed) passed near the planets Jupiter and Mars on March 18, 2020. They were close enough together that all three fit comfortably in the 4.5° field of view of my 15x56 binoculars. This image of them was captured at 6:31 am EDT from Swede Run in Moorestown, NJ, 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 1/13 second at f/2.8, ISO 800. The image was cropped to a 4:3 ratio (64% of the width x 72% of the height) for a field 6.6° wide x 5.0° high. The original raw frame was set to daylight white balance then cropped, resized and converted to a JPEG in Canon's Digital Photo professional. Mouseover for labels; magnitudes and angular spacings (center-to-center) from SkyTools.

 

The image below better shows Jupiter and Mars on March 18. It was captured in a darker sky at 6:18 am EDT with the same equipment as above. It's a single raw frame exposed 1/5 second at f/2.8, ISO 800, auto white balance, then cropped to 24% of the original frame for a field 2.5° wide x 1.7° high. Again, Canon's DPP was used for cropping, resizing and conversion to a JPEG. Mouseover for labels. Note that the somewhat overexposed "discs" of Jupiter and Mars look larger than they really are for several reasons (atmospherics, optics never being perfect, light spill from saturated pixels, etc.). Therefore, even though Jupiter's actual apparent diameter as given on mouseover is about the same as the spacing between Io and Ganymede, the Jovian disc in the picture looks a bit larger than that spacing.

 

 

Saturn, Jupiter and Mars
March 8, 2020

The planets  Saturn, Jupiter and Mars, were close together along the ecliptic in the constellation Sagittarius on March 8, 2020. Jupiter was 8° west (to the right) of Saturn and Mars was 6.4° west of Jupiter (mouseover for labels). This image of them was captured at 6:28 am EDT from Swede Run in Moorestown, NJ, with a Canon EOS RP mirrorless digital camera (on a fixed tripod) and a Sigma 50 mm f/1.4 Art lens. It's a single raw frame exposed 1/2 second at f/4.0, ISO 6400 and 4200K white balance. This image was cropped to a 16:9 ratio (77% of the width x 65% of the height) for a field 31° wide x 18° high. The original raw frame was mildly adjusted, cropped, resized and converted to a JPEG in Canon's Digital Photo professional.

On March 18, Jupiter, Mars and the Crescent Moon will be close together, close enough to all fit in a typical binocular field. Mars and Jupiter will be at conjunction on March 20, then Mars and Saturn will be at conjunction on March 31, less than a degree apart on both occasions. Mars is moving relatively quickly eastward along the ecliptic now. Jupiter is moving eastward more slowly, and Saturn even slower (generally, as they do go through retrograde loops around opposition), and they will be at conjunction on December 21, 2020, just 0.1° apart. Note that December 21 is also the day of the solstice, the winter solstice for the northern hemisphere.

 

 

Venus and Uranus
March 7, 2020

This weekend, the brilliant planet Venus, magnitude -4.3, was passing near the distant and dimmer Uranus, magnitude +5.9, a difference of 10.2 magnitudes, or 12,000x in brightness. This image of them was captured at 7:21 pm EST on March 7, 2020, from Collins Lane Park in Maple Shade, NJ, with a Canon EOS RP mirrorless digital camera and a Canon 200 mm f/2.8L lens (on a fixed tripod). It's a single raw frame exposed 1.0 second at f/4.0, ISO 3200 and 3800K white balance. This image is uncropped for a field 10.3° wide x 6.9° high with the planets 2.3° apart. The original raw frame was resized and converted to a JPEG in Canon's Digital Photo professional, but otherwise, it's unprocessed. Mouseover for labels. It was not difficult to see Uranus with 15x56 binoculars using Venus as a guide.

 

The planets Venus and Uranus were imaged again at 7:33 pm EST with the same Canon RP camera, but using a Tamron 150 to 600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 350 mm focal length for an uncropped field 5.9° wide x 3.9° high. It was exposed 2.0 seconds at f/8.0, ISO 6400 and 3800K white balance (the same net exposure as the previous image). The original raw frame was resized and converted to a JPEG in Canon's Digital Photo professional, but otherwise, it's unprocessed. Mouseover for labels.

 

 

The Crescent Moon and Uranus
February 28, 2020

The Crescent Moon, 5.4 days old and 24% illuminated, was 6° from the magnitude 5.8 planet Uranus at 8:37 pm EST on February 28, 2020, when they were captured from Collins Lane Park in Maple Shade, NJ, with a Canon EOS RP mirrorless digital camera and a Canon 200 mm f/2.8 lens (on a fixed tripod). It's a single raw frame exposed 0.3 seconds at f/2.8, ISO 6400, 3800K white balance. The illuminated crescent is greatly overexposed in order to show dim Uranus in a murky sky. After mild adjustment, the image was resized and converted to a JPEG in Canon's Digital Photo Professional. It's uncropped, providing a field about 10.3° wide x 6.9° high. At the time, the Moon was in the constellation Cetus the Whale, not a Zodiacal constellation (the moon was at 4.5°S ecliptic latitude), while Uranus was in Aries the Ram, one of the traditional constellations of the Zodiac . Mouseover for labels, but note that labels for Xič and XiČ Ceti are reversed. Uranus was also spotted with 15x56 binoculars shortly after arrival, about 8:30 pm.

 The image below shows the Moon separately captured at 8:37 pm EST with the same equipment, but at a significantly reduced exposure to properly show the crescent. It's a single raw frame exposed 1/125 second at f/4.0, ISO 100, about 12.3 fewer stops, or 5,000x less light than the previous frame, so earthshine is no longer visible and the background sky is black. No adjustments were made, except for cropping, size reduction and conversion to a JPEG in Canon's Digital Photo Professional. The field is about 2.6° wide x 2.0° high.

 

 

 

Venus at Chatsworth Lake
January 15, 2020

 

The planet Venus shines brightly (magnitude -4.0), even through some cloudiness, looking southwest across Chatsworth Lake, where it reflects as a "glitter path" at the bottom of the frame. This image of it was captured at 6:48 pm EST on January 15, 2020, from the Pinelands in Chatsworth, NJ, with a Canon EOS RP mirrorless digital camera (on a fixed tripod) and a Sigma 50 mm f/1.4 Art lens. It's a single raw frame exposed 1 second at f/2.0, ISO 12,800, then mildly adjusted (including setting white balance to tungsten), resized and converted to a JPEG in Canon's Digital Photo Professional. It's uncropped, providing a field 27° wide x 40° high. Mouseover for labels.

 

 

The Hunter Chases the Bull
January 2, 2020

The constellation Orion the Hunter chases his prey, Taurus the Bull (mouseover for labels). This image of them was captured at 1:58 am EST on January 2, 2020, from Carranza Field in Wharton State Forest, NJ, with a Canon EOS RP mirrorless digital camera (on a fixed tripod) and a Sigma 50 mm f/1.4 Art lens through a Hoya "diffuser" filter. It's a single raw frame exposed 2 seconds at f/2.0, ISO 3200, auto white balance, then resized and converted to a JPEG in Canon's Digital Photo Professional. It's uncropped, providing a field 40° wide x 27° high. Betelgeuse, the reddish star at the upper-left corner of the Orion stick figure, has recently shown a noticeable drop in brightness.

 

 

Venus and the Crescent Moon through Clouds
December 28, 2019

Shrouded by some halo-producing cloudiness, the young Crescent Moon, 2.7 days old and 7.4% illuminated, joined the bright planet Venus in Capricornus on the evening of December 28, 2019. This image of them was captured at 5:33 pm EST from the baseball field complex in Maple Shade, NJ, with a Canon EOS RP mirrorless digital camera and a Canon 400 mm f/5.6L lens (on a fixed tripod). It's a single raw frame exposed 0.8 second at f/5.6, ISO 1600, daylight white balance, then mildly adjusted, resized and converted to a JPEG in Canon's Digital Photo Professional. It was not cropped, providing a field 3.4° wide x 5.1° high. At the time, the two objects were 2.7° apart and approximately 15° altitude.

 

The Crescent Moon below was from another image captured at 5:35 pm with the same equipment, but exposed 0.6 seconds at f/5.6, ISO 800, then processed in Digital Photo Professional to reduce the brightness and the cloud halo so that a little of the crater detail would show in the illuminated area. It was cropped to a field 1.35° wide x 1.0° high.

 

 

C/2017 T2 (PANSTARRS) Observed
December 15 & 21, 2019

Third-party images and some background information are posted here.

 

 

Mercury and the Old Moon
November 25, 2019

The old Crescent Moon (lower left) joined the planet Mercury (upper right) on the morning of November 24, 2019. This image of them was captured at 6:03 am EST from Swede Run in Moorestown, NJ, with a Canon EOS RP mirrorless digital camera and a Canon 200 mm f/2.8 lens (on a fixed tripod). It's a single raw frame automatically exposed 1/30 second at f/2.8, ISO 12,800, daylight white balance, then mildly adjusted in Canon's Digital Photo Professional. Not cropped for a field 10.3° wide x 6.9° high. At the time, these two objects were 5.1° apart, the Moon at 4.3° altitude and Mercury at 8.5° altitude. The old Moon was 28 hr 03 min before new (Nov 26, 10:03 am EST), and is 1.7% illuminated. Mercury was 50% illuminated and magnitude -0.31.

 

 

Venus and Jupiter
November 24, 2019

The planets Venus (lower left) and Jupiter (upper right) were slightly less than 1.5° apart when they were captured on November 24, 2019, at 5:27 pm EST from Swede Run in Moorestown, NJ. Taken with a Canon EOS RP mirrorless digital camera and a Tamron 150 to 600 mm f/5.0-6.3 zoom lens (on a fixed tripod) set to 150 mm focal length. It's a single frame automatically exposed 1/20 second at f/5.0, ISO 12,800, daylight white balance, then mildly adjusted in Canon's Digital Photo Professional. Not cropped for a field 13.6° wide x 9.2° high. These two planets reached conjunction in geocentric right ascension at 9 am EST on November 24, 1.4° apart.

 

This view of Venus (lower left) and Jupiter (upper right) was captured two minutes earlier, at 5:25 pm EST on November 24, 2019, with the same camera and lens as the previous image, but the focal length was set to 600 mm, and then it was cropped to about 60% of the original size at a 4:3 ratio, yielding a field 2.0° wide x 1.5° high. Several of Jupiter's satellites are visible, from the upper left, Europa, Io (Jupiter) and Ganymede. Callisto was close to Ganymede and is not readily separable here (vibration from a stiff breeze didn't help). It's a single frame automatically exposed 1/13 second at f/6.3, ISO 12,800, daylight white balance, then mildly adjusted in Canon's Digital Photo Professional.

At the time, Venus was at magnitude -3.9 and Jupiter at -1.9 (so Venus was 6.3x brighter). Venus was at 7° altitude and Jupiter at 7.8° altitude. A line through the Jovian satellites was nearly parallel to the ecliptic. Jupiter had a +0°09' ecliptic latitude while Venus was at -1°16' ecliptic latitude.

 

 

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Last Update: Friday, May 29, 2020 at 04:07 PM Eastern Time