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Mars at Perihelic Opposition
July 27, 2018

I observed Mars on July 27, 2018, between 1:00 and 1:40 am EDT, from my Maple Shade, NJ, backyard with a Stellarvue 130 mm, f/7 apo refractor, mainly at 253x, using a Stellarvue Optimus 3.6 mm, 100 eyepiece. In particular, I was viewing Mars (in the scope plus a glance with unaided eyes) at 1:13 am EDT, the moment of opposition and the moment when it crossed the meridian for my location, essentially at 40N-75W. At the time, Mars was 24.3 arc seconds in apparent diameter and 24.7 altitude, somewhat low because of its -6.5 ecliptic latitude in southwest Capricornus.

Due to the global dust storm in progress on Mars (which may be subsiding slightly), surface detail was sparse. With patience at the eyepiece, I could make out a small, not-exactly-white spot representing the South Polar Cap and a slight whitish rim at the northern limb representing the Northern Polar Hood. There was also a vague, faint horizontal darkish band across the southern reaches of the disc, which did not show enough detail to match it to any of the Mars surface feature charts, although based on the date and time, those charts indicate it was mainly Mare Sirenum.

I do not have a close-up picture of Mars at opposition (I'm not capable of such high magnification, high resolution  imagery), but Mike Keith of the South Jersey Astronomy Club (of which I'm also a member) did capture such an image at 12:34 am EDT on July 27, roughly half to one hour before the time span of my observations. He also captured high quality images of Jupiter and Saturn that same night, all presented in the montage shown below...

Mars, Jupiter and Saturn by Mike Keith. Celestron C8, 2x Powermate, ZWO ASI224mc camera.

Mike's image of Mars shows, with considerably more contrast and detail, the features I saw visually in the 130 mm refractor on the morning of July 27, 2018. I regret that I didn't also take a look at Jupiter and Saturn earlier in the evening.

Update: It was pretty hazy on Wednesday night, August 15, 2018, and Mars wasnt the brilliant beacon its been recently because of the haze, but I thought this might afford some decent seeing. So, I decided to get out my 80 mm, f/6 apo refractor for a quick look from the backyard around 11:30 pm EDT. Transit was at 11:35 pm and Mars was 23.3" apparent diameter. Using an Explore Scientific 4.7 mm, 82 deg eyepiece yielding 102x and a 48 arc minute true field of view, Mars looked steady (i.e., seeing was at least good, if not very good). I used a diagonal, so the view was correct vertically, reversed left-to-right.

Despite the relatively small aperture and low magnification, I quickly saw some detail. There was a darkish, inverted T-shaped feature just left (west) of the central meridian. The horizontal portion of the T was below the equator and below that, there was a disc-like area that was a bit lighter in color than the rest of the non-dark surface. Finally, there was a whitish patch along the bottom limb, a tad left of center. However, its visibility varied with the momentary seeing, and it periodically showed a dark rim at its upper edge. Im not a Martian surface feature expert, but I suspected the darkish vertical extension was Syrtis Major, the lighter disc was Hellas, and of course, the South Polar Cap was at the bottom limb. So, it looks like the obscuring effect of the Martian dust storm is truly to diminishing. Next time, Ill get out the 130 mm refractor and have a better view, before Mars drops below 20 arc seconds diameter after September 5.

When I opened WinJUPOS for Mars set to the time of observation and a refractor+diagonal orientation, I was pleasantly surprised to see a good match with my eyepiece view (see the WinJUPOS synthetic image below). It also corresponded with S&Ts Mars Profiler utility, which confirmed my suspected identities above. The Mars Profiler indicated Mare Tyrrhenum and Mare Serpentis formed the darkish horizontal band below Syrtis Major, perhaps extending to Sinus Sebaeus and Sinus Meridiani (the "pipe") towards the east (on the right like the eyepiece view).

Mars on August 15, 2018, at 11:30 pm EDT, N up, E right; from WinJUPOS. The small red circle is the sub-solar point.

 

I subsequently found the image below in ALPO-Japan's Mars section. It was captured about the same time as I was observing and shows largely what I saw. In particular, it shows the fleeting dark rim at the upper edge of the South Polar Cap. 

Mars on August 15, 2018, at 11:18 & 11:25 pm EDT (Aug 16 UT), N up, E left; from ALPO-Japan.

 

 

 

Comet C/2017 S3 (PANSTARRS)
July 19, 2018

This image shows Comet C/2017 S3 (PANSTARRS), captured on July 19, 2018, at 2:51 am EDT from Carranza Field in Wharton State Forest, NJ. The comet is the small bluish-green spot in the bottom-left quadrant. It is next to the magnitude 7.4 star, HD 31779 in the constellation Camelopardalis, near the Auriga-Perseus border. Mouseover for labels. This comet experienced a couple of outbursts in July 2018 and is currently significantly brighter than originally predicted by the standard ephemeris. It was easily seen with 15x56 binoculars on the morning of July 19 at Carranza (under a clear, dark sky).

The image was taken with a Canon 6D digital SLR camera and a Canon 200 mm f/2.8L telephoto lens (on a fixed tripod). It was exposed 4 seconds at f/3.5, ISO 6400, 4000K white balance, and then cropped to about 57% of the original size for a field about 5.9 wide x 3.9 high. Otherwise, it's unprocessed.

I've also labeled the position where the comet was seen with the 15x56s on the morning of July 18 from Maple Shade, NJ, although with much more difficulty under partially cloudy, light-polluted suburban skies. Update: I saw C/2017 S3 (PANSTARRS) again on the morning of July 20 from Swede Run in Moorestown, NJ. It was picked up at 2:26 am with 15x56 binoculars and then subsequently with an 85 mm spotting scope. It did not appear as bright as it did the previous morning at Carranza Field, but Swede Run is essentially a suburban location, and on top of the that, fog and haze were developing, reducing the transparency. It was certainly brighter than July 18 in Maple Shade. Update: As of July 21, reports on the comet e-groups indicate C/2017 S3 is starting to fade again. Is this a temporary bump in the road, or the beginning of the end? This comet has already been surprising, so we'll just have to wait and see what happens as it approaches perihelion on August 15.

 

 

The Crescent Moon and Venus
July 15, 2018

The 2.9-day-old, 12.3% illuminated Crescent Moon was 2.66 from the planet Venus (center to center) when this image of them was captured at 8:48 pm EDT on July  15, 2018, from the baseball field complex in Maple Shade, NJ. This is a single frame taken with a Canon 6D digital SLR camera and a Canon 400 mm f/5.6L telephoto lens (on a fixed tripod), then cropped vertically to a 16:9 ratio for a field about 5.1 wide x 2.9 high. It was exposed 1/400 second at f/6.3, ISO 3200 and daylight white balance. Since it was only 21 minutes after sunset, the sky was still fairly blue. The image below was taken 25 minutes later in a darker sky.

 

The Crescent Moon was 2.44 from the planet Venus (center to center) when this image of them was captured at 9:13 pm EDT on July  15, 2018, from the baseball field complex in Maple Shade, NJ. This is a single frame taken with a Canon 6D digital SLR camera and a Canon 400 mm f/5.6L telephoto lens (on a fixed tripod), then cropped vertically to a 16:9 ratio for a field about 5.1 wide x 2.9 high. It was exposed 1/2 second at f/5.6, ISO 1600 and daylight white balance. This is an additional 7 stops of exposure compared to the first image. It was now 46 minutes after sunset, and some blue remained in the sky. Unfortunately, the sky was also somewhat cloudy and hazy, so the longer exposure in a darker sky shows glowing halos around them, as well as earthshine on the Moon. Magnitude +3.9 Rho Leonis is faintly visible below-left of magnitude -4.1 Venus, which is 8 magnitudes, or 1,600x brighter than Rho. Mouseover for labels.

 

Here's a snapshot of the photo setup for these Moon+Venus images. It was taken with my iPhone 5s at 8:52 pm. Exposed 1/24 second at f/2.2, ISO 320. The Canon 6D camera is attached to a white Canon 400 mm telephoto lens, the tripod foot of which is attached, via an Arca-Swiss style plate, to a Acratech GP ball head (in the gimbal position) on top of a Benro carbon fiber tripod. I use an infrared remote to trigger the shutter, so there's no cord dangling down. I meant to move onto the grass after setting up, but I forgot. Mouseover for labels. I've also indicated the spot where Mercury was subsequently spotted with 10x50 binoculars.

 

 

 

The Crescent Moon and Aldebaran
July 10, 2018

The 26.5-day-old, 11.2% illuminated and earthshine-filled Crescent Moon was exiting the Hyades star cluster on July  10, 2018, when this image of them was captured from Swede Run in Moorestown, NJ, at 4:25 am EDT, 75 minutes before sunrise, and 2.77 days before the next new moon on July 12 at 10:48 pm. This is a single frame taken with a Canon 6D digital SLR camera and a Tamron 150 to 600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 600 mm focal length, then cropped to 90% of the original frame, producing a field about 3 wide x 2 high. It was exposed 0.8 seconds at f/6.3, ISO 3200, 4200K white balance. The moon passed about 4 arc minutes from the first-magnitude star Aldebaran, which is just off the southern cusp in this image (one needed to be farther north to see an occultation). Mouseover for labels.

The image below is a much-shorter exposure that shows some detail in the illuminated crescent at the expense of not showing the earthshine. Aldebaran, below the southern cusp of the Moon, shows a reddish color, some intrinsic but certainly some red contributed by the atmosphere at the low altitude, about 9.5 at the time.

This is a single frame taken at 4:17 am with a Canon 6D digital SLR camera and a Tamron 150 to 600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 600 mm focal length, then cropped to 38% x 56% of the original frame, producing a field about 1.3 square. It was exposed 1/125 second at f/6.3, ISO 3200 (100x less exposure than the previous image at 0.8, or 1/1.25 seconds), 3600K white balance.

 

 

 

Mercury Update - June 2018

Mercury has seven elongations in 2018. The initial sighting for each of these is tabulated below:

 

Sequence

Initial Sighting Date (2017/18)

Observing Location

Greatest Elongation (2018)

#1

December 24, 6:10 am EST Swede Run, Moorestown, NJ

January 1, western (morning)

#2

February 26, 5:56 pm EST Baseball Fields, Maple Shade, NJ

March 15, eastern (evening)

#3

April 22, 5:26 am EDT Old Mart Site, Pennsauken, NJ

April 29, western (morning)

#4

June 14, 8:41 pm EDT Swede Run, Moorestown, NJ

July 12, eastern (evening)

#5

   

August 26, western (morning)

#6

   

November 6, eastern (evening)

#7

    December 15, western (morning)

Click here for the sighting details of each elongation this year. The current sighting streak is now 48 elongations in a row, starting in January 2011, which includes seven complete calendar years of six or seven elongations. The years 2011 and 2015 had seven (7) elongations each, while 2012, 2013, 2014, 2016 and 2017 had six (6) each. Click here for sightings from last year's elongations.

 

 

(4) Vesta Nears Opposition
June 5, 2018

This picture of the Milky Way region above Sagittarius was captured on June 5, 2018, at 12:44 am from Carranza Field in Wharton State Forest, NJ. However, the Milky Way was not the prime target, rather it was the asteroid (or minor planet), (4) Vesta. This is a single frame taken with a Canon 6D digital SLR camera on a fixed tripod and a Tamron 45 mm f/1.8 lens, which provides a field about 43.5 wide x 30 high. Exposed 4 seconds at f/2, ISO 3,200 and 3,600K white balance. Other than size reduction for this web page, no processing was applied. Mouseover for labels. Note: The object labeled M18 is actually M16.

 

I went to Carranza in hope of seeing Vesta with unaided eyes since it was at magnitude 5.7 (it will reach magnitude 5.3 at opposition on June 19, more about that here). I arrived just before midnight on June 4 and stayed until about 1 am EDT on June 5. Vesta would transit at 2:13 am, but the almost-third-quarter Moon rose at 12:53 am. The Milky Way through the Summer Triangle and continuing down into Sagittarius was prominent, but not billowing. The air seemed moist after heavy rain over the weekend and dew was forming on my camera and tripod. However, it was quite pleasant to be under a starry sky for a change, and sweeping the sky with 15x56 binoculars revealed numerous deep-sky objects, especially in the pictured Milky Way. And for a sonic background, the chorus frogs were going strong at nearby Skit Branch.

Vesta was easily visible in the binoculars, but I was not able to make a definite sighting of it with unaided eyes. I think I might have glimpsed Vesta with averted vision a couple of times when I was able position M24, the Sagittarius Star Cloud, in the averted sweet spot (nice view) and I thought I was seeing a ghostly outline of the dark Prancing Horse Nebulae (which includes the dark Pipe Nebula), but Vesta was much too fleeting to be claimed as a sighting. One has to guard against the brain filling-in things that are expected, but not really visible. I was also unable to see M13 with unaided eyes, something I've done many times in the past, even though it was virtually at the zenith. Perhaps the transparency wasn't that good, or perhaps advancing age is catching up with my eyes. However, looking at SkyTools, Vesta was 28 altitude at 12:44 am, so the airmass for it was 2.1, which yielded a mean extincted magnitude of 6.6, which would indeed be dimmer than the nominal magnitude 6 limit for unaided eyes (and the dimmest I've confirmed seeing in the past from New Jersey is magnitude 6.1). I also failed to see M51 (about 60 altitude) in the 15x56s, which I was able to do without difficulty last month at Atsion in Wharton State Forest.

Note that Atlantic City, with its attendant light pollution, is only about 30 miles away in nearly the same direction as Vesta in the picture (≈160 azimuth), hence the light cone rising from the tree tops in the middle of the frame. Last, but not least, I need a better way to block Saturn besides a hand at the end of my outstretched arm, which quickly becomes tiresome; perhaps a piece of cardboard at the end of a stick? Saturn may not seem particularly bright in a suburban sky, but under a dark sky looking for a nearby faint object (Vesta was less than 7 away), it looks bright and becomes disruptive. In any case, a couple more weeks remain before Vesta's opposition and maximum brightness and before the moon interferes. Let's hope for some more clear nights! Scroll down for reports on later attempts.

 

The image below was taken at 12:19 am EDT with the 6D and a Canon 100 mm f/2.8L macro lens on a fixed tripod, providing a field about 20 wide x 14 high to better show Vesta. Exposed 4 seconds at f/2.8, ISO 12,800, 3,600K white balance. No processing was applied besides size reduction. Mouseover for labels. Note: The object labeled M18 is actually M16.

 

The image below is a 41% crop of the previous image taken with the 100 mm lens, providing a field about 8.4 wide x 5.6 high. Again, no processing was applied besides the cropping and size reduction. Vesta was located in front of a small asterism of several stars in the magnitude 8 to 10 range that was shaped a bit like an arrowhead. The stars of the "arrowhead" were visible in the 15x56 binoculars, but Vesta is currently moving about 0.22/day west (retrograde motion, to the right in this view), so it was only there temporarily. Mouseover for labels.

 

Refer to the separate Vesta page for observation updates.

 

 

The Great Courses Ad
Mystery Objects in the Hyades and the Foot of Castor

 

 

The Waxing Gibbous Moon
May 24, 2018
 

The 9.6-day-old, 80.2% illuminated, waxing gibbous Moon was captured on May 24, 2018, at 10:46 pm EDT from Maple Shade, NJ. This is a single frame taken with a Canon 7D Mark II digital SLR camera at the prime focus of a Stellarvue SVA 130T f/7 triplet apochromatic refractor (910 mm focal length) on an altazimuth mount. It was cropped to a third of the sensor's area, yielding a field about 0.6 square. It was exposed 1/1000 second at f/7, ISO 400, which is an exposure equivalent to the "looney eleven" rule-of-thumb. Besides cropping, only mild adjustment was applied, mainly by reducing color saturation to zero. This is a direct view with the zenith up, south down and celestial east to the left.

The image below is a severe crop of the original frame (9% of the linear dimensions, or less than 1% of the original area of the frame) producing a field 7.5 x 5.0 arc minutes. It shows the craters Messier and Messier A in Mare Fecunditatis, two-thirds of the way from the lunar center to the right limb as pictured above. Messier A is on the left and has prominent rays extending to the lunar west (left). The two craters and the rays are believed to be the result of a low-angle impact.

 

The image below is also a severe crop of the original frame (6% of the linear dimensions, or 0.4% of the original area of the frame) producing a field 5.1 x 3.4 arc minutes. It shows the crater Plato (left of center) and Vallis Alpes (the straight gouge right of center). They're near the top of the moon in the full image.

 

 

 

Four (4) ISS + Cygnus Passes Overnight
May 23-24, 2018

 

Six (6) ISS Passes, One (1) with Cygnus, Overnight
May 21-22, 2018

 

Antares Rocket Launch, taking the Cygnus
Cargo Spacecraft, OA-9, to the ISS
May 21, 2018

 

Jupiter, GRS & Io + Shadow Transits
May 8, 2018

 

 

 

The Crescent Moon in the Hyades
April 18, 2018

The two-day-old, 11% illuminated and earthshine-filled Crescent Moon was in the Hyades star cluster on April 18, 2018, when this image of them was captured from Maple Shade, NJ, at 8:54 pm EDT, 74 minutes after sunset in a hazy sky, soon to become cloudy. This is a single frame taken with a Canon 6D digital SLR camera and a Tamron 150 to 600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 250 mm focal length, then cropped to about three-quarters of the original frame, producing a field 5.5 wide x 4.9 high. It was exposed 1.6 seconds at f/5.6, ISO 1600. Mouseover for labels. All of the stars here are in Taurus the Bull, so the labeled Bayer letter or Flamsteed number would be suffixed "Tauri." The blue V-shaped lines frame the face of the Bull in the Hyades. The horns would extend about 15 more-or-less vertically from Aldebaran (α) and Ain (ε) to Zeta (ζ) and Beta (β) Tauri respectively (β = Alnath). Note: The labels for Theta 1 & 2 (θ & θ) are reversed.

Notice the magnitude 5.6 star, 63 Tauri, just above the moon. I saw it near the lunar limb on the camera's viewing screen during the session, and reviewing circumstances afterwards with SkyTools, saw that it was occulted by the moon at 9:08 pm (the moon is moving eastward, nominally to the upper-left in this view, about its own half-degree diameter per hour). Looking through the images, the last one with 63 Tauri visible (below) was taken at 9:07 pm EDT, 13 minutes later.

63 Tauri had vanished in the following frame that was time-stamped 9:08 pm (not shown). Taken with a Canon 6D digital SLR camera, which has an internal GPS that sets the clock, and a Tamron 150 to 600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 205 mm focal length, then cropped to about one-quarter of the original frame, producing a field 2.7 wide x 1.8 high. It was exposed 1.3 seconds at f/5.6, ISO 800. Mouseover for labels.

 

 

Venus and Uranus
March 30, 2018

The planets Venus and Uranus were at conjunction on March 28, 2018, and less then 5 arc minutes apart after sunset. However, it was cloudy that night, as it was on the preceding and following nights, March 27 & 29, when they were little more than 1 apart. Finally, on March 30, 2018, despite rain in the afternoon and a poor weather forecast for the evening, it cleared out nicely shortly before sunset at 7:22 pm EDT. This picture of them was taken at 8:13 pm from the baseball field complex in Maple Shade, NJ, with a Canon 6D digital SLR camera and a Canon 200 mm f/2.8L lens (on a fixed tripod), then cropped to about half the original size for a field 5.0 wide x 3.7 high. It was exposed 0.8 second at f/8, ISO 1600.

In the picture, brilliant Venus is shining at magnitude -3.9, so it's overexposed and  shows a crown of diffraction spikes generated by the lens diaphragm. The magnitude +5.9 star HD 11257 is 15 arc minutes from Venus at the 1 o'clock position, the magnitude +4.3 star Omicron Piscium is 2.1 from Venus at the 7 o'clock position and barely-visible magnitude +5.9 Uranus is 2.3 from Venus at the 5 o'clock position (mouseover for labels). At the time of the picture, Venus was at 8.2 altitude and Uranus was at 6.0 altitude. Venus is moving eastward from the sun, and becoming higher in the evening sky, following superior conjunction on January 9, 2018. Uranus is dropping in the evening sky and will be at conjunction with the sun on April 18, 2018.

The 9.8 magnitude difference between Venus and Uranus is equivalent to a difference of 8,300 times in brightness, or 13 photo stops, hence the difficulty in showing them both with a single exposure and no localized processing to enhance Uranus. In addition, the difference in the already-low altitude causes greater atmospheric extinction of Uranus, and the noticeable twilight gradient also diminishes Uranus' visibility in the photo. Uranus and Omicron Piscium could not be seen with 16x70 binoculars during the March 30 session from 8:00 and 8:30 pm. My last visual sighting of Uranus (using an 80 mm apo refractor at 72x) was on March 26 when it was about 2.4 above Venus. It was not easy to see.

 

 

The Crescent Moon, Venus and Mercury
March 18, 2018

The 1.5-day-old Crescent Moon joined the planets Venus and Mercury in this view captured on March 18, 2018, from Swede Run in Moorestown, NJ, at 8:01 pm EDT, 51 minutes after sunset. The Moon was at 4.3 altitude and 2.5% illuminated. Venus, 3.9 from the moon, was at 5.3 altitude and magnitude -3.9. Mercury, 3.8 from Venus, was at 7.2 altitude and magnitude +0.4. It's a single uncropped frame taken with a Canon 6D digital SLR camera and a Canon 200 mm f/2.8L lens (on a fixed tripod). It was exposed 1/10 second at f/2.8, ISO 1600, daylight white balance. Mouseover for labels. Here's my 2018 Mercury sighting page.

 

 

Venus and Mercury
March 3, 4 & 5, 2018

In early March 2018, both Venus and Mercury were in eastern elongation and were visible low in the west after sunset. At time, Mercury was moving eastward more rapidly than Venus and passed it, reaching conjunction in geocentric right ascension on March 5 at 1 pm EST. Their appulse (closest approach) for an observer at 40N-75W, only a few miles from Maple Shade and Moorestown, NJ, would be on March 4 at 1 am EST. The closest visible approach was on the evening of March 3 when they were 1 05' apart at 6:30 pm EST. On March 4, they were 1 09' apart and on March 5, they were 1 29' apart at 6:30 pm. During these three days, Venus was at magnitude -3.9 while Mercury was at magnitude -1.2 on March 3 & 4, magnitude -1.1 on March 5. Venus was seen with unaided eyes on all three dates, but obvious on the clear evenings of March 4 & 5. Mercury was also readily visible with unaided eyes on March 4 & 5. Of particular note on March 5, both were seen with 10x50 binoculars at 5:52 pm, 4 minutes before sunset, when Mercury was at 13.5 altitude. Check the Mercury 2018 page for more details about visual observations on these dates, under Elongation #2.

The pictures below show Venus and Mercury on March 3, 4 & 5, 2018. The scale varies a little between them, but they clearly show Mercury (on the right) increasing in altitude relative to Venus on successive evenings. Mouseover for labels.

March 3, 2018, at 6:36 pm EST (42 minutes after sunset) from the baseball field complex in Maple Shade, NJ. Canon 6D digital SLR camera (on a fixed tripod) and a Sigma 70 to 300 mm, f/4-5.6 zoom lens set to 300 mm focal length, then cropped to about 60% of the original size (and a 16:9 ratio), which yielded a field about 4.6 wide x 2.6 high. It was exposed 1/6 second at f/5.6, ISO 800.

 

March 4, 2018, at 6:37 pm EST (42 minutes after sunset) from Swede Run in Moorestown, NJ. Canon 6D digital SLR camera and a Canon 70 to 200 mm, f/2.8L zoom lens (on a fixed tripod) set to 190 mm focal length, then cropped to about 65% of the original size (and a 16:9 ratio), which yielded a field about 7.5 wide x 4.3 high. It was exposed 1/20 second at f/2.8, ISO 800.

 

March 5, 2018, at 6:40 pm EST (44 minutes after sunset) from the baseball field complex in Maple Shade, NJ. Canon 6D digital SLR camera and a Tamron 150 to 600 mm f/5-6.3 zoom lens (on a fixed tripod) set to 329 mm focal length, then cropped to about 84% of the original height (for a 16:9 ratio), which yielded a field about 6.2 wide x 3.5 high. It was exposed 1/4 second at f/5.6, ISO 1600.

 

 

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Last Update: Friday, August 17, 2018 at 02:43 PM Eastern Time