Earthly clouds and galactic clouds

 The sky was exceptionally dark on Tuesday night, with sqml=21.68.  Unfortunately, some passing clouds made wide-field photography difficult.  The following images were obtained with a Sony A7iii + Rokinon 85mm f/1.4 lens, ISO 1600, 30 s.  This lens is the original 9-element aspherical MF version purchased in 2011.

 Can you tell the earthly clouds from the Galactic dust clouds?:

Scorpius.  Kase Astroblast filter.

Deneb and the North American Nebula (top center).  Kase Astroblast filter.

Milky Way and heat lightning

 Monday night the sky was dark.  The Sky Quality Meter was reading sqml=21.60 mpsas.  Off to the east, however, silent flashes of light were intermittently lighting up the sky.  This is often called "heat lightning".  It is just regular lightning, but the storm clouds producing it are too far away for the sound to reach.

The following images were all obtained with a Sony A7iii and a Bower (Samyang) 35mm f/1.4 lens.

Galactic center rising.  Softon filter.  ISO 1600, 30 s.

 Seven minutes later, with the sky illuminated by distant lightning:

The Summer Triangle: Deneb, Vega, Altair.  Softon filter.

 

Melotte 111 in Coma Berenices.  Softon filter.  FOV = 15x10 deg.

Waiting for the Moon

 At 10:50 pm on Sunday night the Moon had technically risen above the distant theoretical horizon, but it was still well hidden by the nearby southern flank of Snowshoe Mountain.  The passing clouds, however, were vividly illuminated by the unseen Moon.

Sony A7iii + Sony 20mm f/1.8 G lens + Sparkle-6 filter.  ISO 1600, 30 s.

In this image above Arcturus is the bright star near center top.  Arcturus is the fourth brightest star in the entire sky and the brightest in the north celestial hemisphere.  Somewhat lower and midway to the right edge of the frame is the constellation Coma Berenices, which is dominated by the star cluster Melotte 111. This cluster is the second closest open star cluster.  Here is a closer look, cropped from the above image:

Melotte 111 in Coma Berenices.  Sony FE 20mm f/1.8 + Hoya Sparkle-6 filter. 31-deg FOV.

This next image of the cluster nicknamed the "Coathanger" was obtained the previous evening, again with the unseen moon brightening the sky.  This cluster is officially designated Collinder 399 and is thirteen times farther away than Melotte 111.

"The Coathanger", Collinder 399.  Canon FD 300mm f/4L + Kase Astroblast filter. 4.6-deg FOV.

The famous RIng Nebula, M57, was also visible in the moon-brightened sky.

Canon FD 300mm f/4L.  ISO 1600, 15 s.

In this image M57 is the pale blue ring near the center.  The bright star below center left is Sulafat (Gamma Lyrae) and the star above center right is Sheliak (Beta Lyrae).

Here is a 1:1 crop of M57, the RIng Nebula:

The RIng Nebula, M57.  1-deg FOV.

 This nebula is a fun challenge to find in small telescopes, and is best appreciated with larger scopes.

Moon and stars

The coming full moon on Friday is the June "Strawberry Moon".   Storms are in the forecast, so these may be the last clear-sky images for a while.

Moon rising over Snowshoe Mtn.  Tuesday 18 June.  Canon FD 300mm f/4.

 A couple hours later:

11.9-d moon, Tuesday 18 June.  AT80EDT.  ISO 200, 1/800 s.

10.9-d moon.  Monday 17 June.  AT80EDT.  ISO 200, 1/1000 s.

The sky brightness with the moon was sqml=19.98.  This is still dark enough to capture some deep-sky objects.

M57, the "Ring Nebula".  AT80EDT, ISO 1600, 30 s. FOV = 0.5 deg.

The Ring Nebula is a planetary nebula in the constellation Lyra.  This type of nebula forms when a star similar to our sun reaches its end of life and expels its outer layers while transforming into a white dwarf star.  

 

9.1-d moon.  Saturday15 June.  AT80EDT, ISO 200, 1/500 s.

Even with a waxing moon past first quarter, the sky brightness was sqml=20.08.  This is darker than a moonless night in Santa Fe.

The great Hercules globular cluster M13.  AT80EDT, ISO 1600, 30 s. 1-deg FOV.

 

8.2-d moon. Friday 14 June.  AT80EDT, ISO 200, 1/400 s.

M4, globular cluster in Scorpius.  1-deg FOV.  AT80EDT, ISO 1600, 30 s.

The sky brightness for this last shot was sqml=20.54 in the direction opposite from the moon.

Waiting out the Moon

 Tuesday night (11 June) the Moon did not set until well after midnight.  I wanted to test a specific lens on the Milky Way, so I just had to wait.

5.5-d Moon.  E-M1iii + Canon FD 300mm f/4. ISO 200, 1/400 s.

I did not wait for official Moonset (12:44 am Wed).  When the Moon dropped below the Bristol Head ridgeline around midnight, that was good enough.  The sky brightness was still a respectable sqml=21.35.

 

Milky Way rising. Sony A7iii + Rokinon 24mm f/1.4 + Sparkle-6 filter.  ISO 1600, 30 s.

Summer Triangle (Deneb, Vega, Altair). Rokinon 24mm f/1.4 + Sparkle-6.

 This copy of the lens has some problems in the upper left corner. In spite of this, the results are not bad considering that the moon was lurking just out of sight.

Wide-angle Milky Way

 This is probably one of the last Milky Way shots until the moon disappears from the evening sky.  The lens was a Laowa 7.5mm f/2 on a E-M1iii camera.  This is the widest-angle non-fisheye lens that I have for this system.  The sky was nicely dark at sqml=21.55.  Green airglow is evident at lower elevations.

08 June.  Laowa 7.5mm f/2 + Sparkle-6 filter.  ISO 1600, 60 s.

Hello Moon, goodbye Dark Sky

 The moon is in the night sky again, currently 2.6-d past new.  Milky Way viewing will soon be confined to the hours past midnight.  As the June 20 Summer Solstice approaches twilight extends to almost 10 pm MDT, further cutting into dark-sky viewing.  Dark-sky evenings won't return until the end of June.  

2.6-d moon setting over Bristol Head.  Sony A7iii + Nikon 180mm f/2.8 Ai-S.

Omega Centauri through the fading twilight and low-elevation airglow -- still a magnificent sight.

Omega Centauri.  E-M5iii + Rokinon 135mm f/2.  ISO 800, 30 s.

Omega Centauri, 2-deg FOV.  10 million stars!

Scorpius rising over Snowshoe Mountain:

E-M1iii + Sigma 30mm f/1.4 + Hoya Softon filter.  ISO 1600, 60 s.

 

Sigma 30mm f/1.4 + Softon.

Nebulosity around Antares:

E-M5iii + Rokinon 135mm f/2.  ISO 1600, 60 s.

The Milky Way rising through green airglow:

E-M1III + Leica 9mm f/1.7 + Sparkle-6 filter.  ISO 1600, 60 s.

Comet 13P/Olbers

 Comet 13P/Olbers is a periodic comet (hence the "P") similar to Halley's Comet.  It has a 69-year period and was discovered in 1815 by German astronomer Heinrich Wilhelm Matthias Olbers.  In its four recorded appearances it has never been brighter than the threshold of naked-eye visibility.  It is currently low in the western sky during twilight.  I was able to capture an image of the comet against the fading sky just before it set over Bristol Head.

E-M5iii + Rokinon 135mm f/2.  ISO 800, 30 s.  9:46 pm MDT, 5 June.

 

Olbers also discovered the second asteroid, (2) Pallas, and the fourth, (4) Vesta.  Pallas is currently visible high in the late evening sky near the constellations Corona Borealis and Hercules.

The white circle marks the position of Pallas on 2 June.  Sigma 30mm lens + softon filter.

 

A close-up crop from the previous image.

Pallas currently shines at magnitude 9.1.  It is the third largest asteroid behind (1) Ceres and (4) Vesta.  At the time of its discovery in 1802 it was considered to be a new planet.