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Mercury, Regulus and Mars
September 9, 2017

Mercury was near Regulus and Mars before sunrise on September 9, 2017. This picture of the the trio was captured at 5:41 am EDT from Carranza Field in Wharton State Forest, NJ, 40 minutes after the start of astronomical twilight (5:01 am) and 53 minutes before sunrise (6:34 am). Mercury was 1.0 southwest (to the right) of Regulus (Alpha Leonis) and Mars was 2.5 east (below-left) of Regulus, which was 5.3 altitude at the time. Mouseover for labels. Mercury has brightened significantly to magnitude +0.1, from +1.7 when observed on September 4, and was easily seen with unaided eyes once it cleared the trees at 5:30 am. It was still visible at 6 am when I left the field. Taken with a Canon 6D digital SLR camera and a Canon 200 mm f/2.8L lens (on a fixed tripod), then cropped to about 70% of the original size, yielding a frame about 7.8 wide x 4.4 high. Exposed 1 second at f/5.6, ISO 800.


While waiting for Mercury and its companions to rise and clear the trees on September 9, 2017, I took this picture of Venus at 4:55 am. The moon, three days past full and still 89% illuminated, was high in the sky behind my right shoulder, so the field itself is illuminated in this long exposure. Venus, of course, is the brilliant object in the bottom-left quadrant at 9 altitude. It's in Cancer, just west (above) the border with Leo. Above, and slightly right of Venus, is Messier 44, the Beehive Cluster in Cancer. Towards the upper-right corner is the first magnitude star Procyon, and above it, Gomeisa. This pair forms the single-line stick figure of Canis Minor. Mouseover for labels. Taken at 4:55 am EDT with a Canon 6D digital SLR camera (on a fixed tripod) and a Tamron 45 mm f/1.8 lens, producing a field about 43 wide x 30 high. Exposed 6 seconds at f/4, ISO 1600 (that's about 4.5 stops more exposure than the Mercury-Regulus-Mars twilight image above).



The Nearly-Full Moon
September 4, 2017

Here's the waxing gibbous moon at 10:02 pm EDT on September 4, 2017, about 29 hours before new at 3:03 am on September 6. Taken with a Canon 7D Mark II digital SLR camera and a Tamron 150-600 mm f/5-6.3 zoom lens on a fixed tripod, set to 600 mm focal length then cropped to a little more than 50% of the original frame (yielding a field about 1.1 wide x 0.8 high). Exposed 1/800 second at f/8, ISO 800. Mouseover for labels.



Large Sunspots
September 4, 2017

Here's the sun at 1:33 pm EDT on September 4, 2017, showing a couple of prominent sunspot groups. The spots could also be seen with unaided eyes (using proper solar filtration of course). For most of this year, sunspots have been weak or nonexistent as we head to an expected deep solar minimum. Taken with a Canon 7D Mark II digital SLR camera and a Tamron 150-600 mm f/5-6.3 zoom lens on a fixed tripod, set to 600 mm focal length then moderately cropped. Exposed 1/3200 second at f/22, ISO 1600, through an ND5 filter, which yields a natural white color, but the sun was colorized with Corel PaintShop Pro. Focus and exposure settings are not optimum as I still need to improve camera technique in bright sunlight. Mouseover for active region labels.



Mercury Update - September 2017

Mercury has six elongations in 2017. The initial sighting for each of these is tabulated below:


Initial Sighting Date (2017)

Observing Location

Greatest Elongation (2017)


January 5, 6:15 am EST Old Mart Site, Pennsauken, NJ

January 19, western (morning)


March 16, 7:16 pm EDT Baseball Fields, Maple Shade, NJ

April 1, eastern (evening)


May 14, 5:05 am EDT Old Mart Site, Pennsauken, NJ

May 17, western (morning)


June 26, 8:33 pm EDT New Albany Rd, Moorestown, NJ

July 29, eastern (evening)


September 4, 5:50 am EDT Swede Run, Moorestown, NJ

September 12, western (morning)



November 23, eastern (evening)

Click here for the sighting details of each elongation this year. The current sighting streak is now 43 elongations in a row, starting in January 2011, which includes six complete calendar years of six or seven elongations each (click here for sightings from last year's elongations). This demonstrates that locating and seeing Mercury is not nearly as difficult as many suppose. It just takes some planning and a little effort.



Partial Solar Eclipse
August 21, 2017

Clouds developed early in the afternoon of August 21, 2017, the day of the total solar eclipse, although it was only a partial eclipse in the Philadelphia area, including Maple Shade, NJ, where this picture was taken at 2:25 pm EDT, 20 minutes before the maximum 75% obscuration. It's the only half-decent shot of the few taken during brief gaps in the clouds, streaks of which can be seen in the picture. Taken with a Canon 6D digital SLR camera and a Tamron SP 150-600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 600 mm focal length. It was exposed 0.6 seconds at f/11, ISO 400 through an ND5 filter (ND5 = neutral density, 10^5 or 100,000x attenuation, about 16.6 photo stops). Update, September 7, 2017: The image was re-cropped to about 57% of the original size, and re-centered, yielding a field about 2.0 x 1.3. The solar crescent was also colorized from its natural white with Corel PaintShop Pro.

For a collection of superb eclipse images, check out Jerry Lodriguss' site.



The Crescent Moon Nears the Eclipse
August 20, 2017

On August 20, 2017, the crescent Moon rose at 4:40 am EDT, 14 minutes after the start of astronomical twilight and 85 minutes before sunrise. This picture of it was captured at 5:16 am when it was 2.3% illuminated and 4 altitude as viewed from Carranza Field in Wharton State Forest, NJ. That morning's crescent Moon had a solar elongation of 17.5 and it was the last time it would be readily visible before the solar eclipse on August 21. It was 33 hr 14 min before new when the picture was taken with a Canon 6D digital SLR camera and a Tamron SP 150 to 600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 600 mm focal length (not cropped). It was exposed 1 second at f/8, ISO 12,800 and  3600K white balance. The moon was last seen with unaided eyes, after first locating it with 10x50 binoculars, at 6:05 am from the side of a field next to Seneca High School on Carranza Rd. At 6:10 am, the thin crescent was still fairly easy in the 10x50s, but it could no longer be seen with unaided eyes. The moon was 32 hr 20 min before new when last viewed at 6:10 am. Click here for additional pictures from August 20 at 300 mm and 150 mm focal lengths.



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Last Update: Saturday, September 16, 2017 at 12:41 PM Eastern Time