Thursday, November 27, 2025

Star trails on Thanksgiving evening

There were some thin clouds, mostly to the south, that had the potential to ruin this 78-min exposure.  However, it looks like it was mostly successful.  The landscape was illuminated by the first-quarter moon.  

Equipment: Olympus E-M1iii + Rokinon 7.5mm f/3.5 fisheye lens.


 

After the moon sets

 The official start of winter is more than three weeks away, but the winter constellations are now rising above Snowshoe Mountain in the late evening.  Shortly after moonset on Tuesday the measured sky brightness was 21.38 mpsas.  

Two cameras were used for these images: Olympus E-M1iii + Leica 15mm f/1.7 lens + Hoya Sparkle-6 filter, and Sony A7iii + Sony FE 50mm f/1.8 lens + Hoya Softon filter.

Jupiter (left) and Orion rising.  Leica 15mm.

Orion.  Sony 50mm.

Jupiter, Castor and Pollux.  Sony 50mm.

The view to the south featured the less-impressive constellation Cetus.  However, this constellation contains a nearby star, Tau Ceti (τ Ceti), that is only 11.9-ly distant and the 19th closest star system.  Notably, it is also the seventh-nearest naked-eye star.

Tau Ceti (circled) and Saturn (upper right corner).  Leica 15mm.

 
A closer look.  Sony 50mm

credit: SkySafariAstronomy.com

Neptune (circled) and Saturn.



Tuesday, November 25, 2025

Late November constellations

 These pictures were obtained near 8:30 pm last night with the temperature in the low 20's F.  The eventual low was about 5° F the next morning.  Temperatures this low are a problem for doing polar alignment of the star tracking mount, because the green laser that is used for lining up on Polaris does not work well in the cold.

The camera used was a Sony A7iii + Rokinon AF 85mm f/1.4 FEII lens + Hoya Softon filter.  The  measured sky brightness was sqml=21.31 mpsas.  Some faint red airglow was evident at lower elevations. 

Lyra

 
credit: SkySafariAstronomy.com

Cassiopeia

credit: SkySafariAstronomy.com

Perseus

credit: SkySafariAstronomy.com

Auriga

credit: SkySafariAstronomy.com
The Pleiades, Hyades, and Uranus (circled)

credit: SkySafariAstronomy.com




Sunday, November 23, 2025

Some stars before the storm

 There is a 3.5-inch blanket of new snow on the ground this morning (Sunday).  Last night started out clear, with a nice view of the 2.8-day crescent moon during twilight.

Olympus E-M5iii + 40-150mm f/4.

 Clouds were moving in from the south as I photographed the Summer Triangle in the west over Bristol Head.

Olympus E-M1iii + 12mm f/2 + Hoya Sparkle-6 filter.

 There are three famous double stars in the region of the Summer Triangle.  They are Epsilon Lyrae ("Double Double"), Albireo (Beta Cygni), and 61 Cygni (the "Flying Star").  The finder chart below shows where they are located.  I photographed them with a GSO 4.5-in (114 mm) f/12.5 Classical Cassegrain (1427 mm focal length) and a Sony A7iii camera.

 

credit: SkySafariAstronomy.com

Vega and Epsilon Lyrae (upper right).  Rokinon 135mm f/2.

Epsilon Lyrae.  Full image area.  North to the right. GSO Cassegrain.

Epsilon Lyrae, a closer look.  North is up.

Each of the two stars seen here is also a double star, hence the nickname "Double Double".  Resolving the two tight pairs requires good optics and high magnification (about 100x or more).

Albireo.  Full image area.  North to the right. GSO Cassegrain.

Albireo, a closer look.  North is up.

Albireo is famous for the contrasting colors of the two stars: golden and blue.

61 Cygni. Full image area. North to the right. GSO Cassegrain.
 
61 Cygni, a closer look.  North is up.

61 Cygni is known as the "Flying Star" because of its large proper motion (movement relative to the background stars).  This rapid movement is related to its close distance:  11.4 ly.  It is the 12th closest star system.

The image quality from the 4.5-inch Cassegrain is less than I would like.  There is some asymmetry to the star images that indicates a probable collimation issue.  I'll have to work on that some day.  For now, this scope is going into the closet.

GSO 4.5-inch Classical Cassegrain
 


Thursday, November 13, 2025

More aurora pictures and the sunpot responsible

 A picture of the sun this morning shows the sunspot responsible for the flare that caused the massive auroral display on Tuesday.  The sunspot is the large one in the upper right quadrant.  It is about to rotate out of sight.

13 Nov, false-color image.  AT80EDT refractor + Lunt solar wedge.

 The auroral display Tuesday night got progressively better over the course of several hours.  At first it manifested as a bright greenish glow on the northern horizon, almost like a false dawn, with barely perceptible red glow filling the northern sky.  Eventually, the green glow transformed into green curtain auroras and the larger red glow was visible to the eye.  For a while, the Bristol Head ridgeline to the west was silhouetted in front of a bright red glow.

 
The beginning.  Sony A7iii + Laowa 15mm f/2.

An hour+ later.

Wednesday night was cloudy here in Creede, so there was no follow up to this great display.  The sky looks normal tonight, with some airglow at low elevations along the horizon. The measured sky brightness varied from 20.92 to 21.05 mpsas, depending on direction.

Western view.  Olympus E-M1iii + Leica 9mm f/1.7 + sparkle filter.

 
Eastern view.

Tuesday, November 11, 2025

Tuesday auroral display: wow!

 A severe geomagnetic storm produced an auroral display Tuesday evening (11 Nov) that was visible even in some southern states.  From here in Creede it was an impressive show.  The red glow was only occasionally visible to the eye, but it lit up the camera display.  Camera sensors are much more sensitive to red than the human eye.  The green curtains, however, were very easy to see and very exciting.  I haven't seen a display like this since I was a kid in the Upper Peninsula of Michigan.

Lots of pictures were obtained in two sessions, but these three were typical of the best part of the display.  Camera: Sony A7iii + Laowa 15mm f/2 lens + Hoya Sparkle-6 filter.

 

East

North

West

Sunday, November 9, 2025

Scraps from last night

 Last night I was able to get in only one shot of Comet Lemmon with the AT80EDT refractor before it set behind the Bristol Head ridgeline.  A second shot showed only the tail:

Tail of Comet C/2025 A6 (Lemmon).  AT80EDT refractor.


The comet is past peak brightness, but without the moon it still shows a nice tail in photographs.

After the comet sank out of sight I turned the telescope to the open star cluster M23 in Sagittarius:

M23

 M23 is just one cluster among many in this densely populated section of the Milky Way.  Here is a finder chart for context:

credit: SkySafariAstronomy.com

 After the star cluster, the dwarf-planet Pluto was a good target:

Pluto (circled) on 08 Nov.

Here is an image from 16 Oct with about the same FOV, taken with a 135mm f/2 lens:

Pluto (circled) on 16 Oct.

Comparison of the two images reveals how much Pluto has moved with respect to the background stars over three weeks.  Pluto is currently about magnitude 14.6 in the constellation Capricornus.

Saturday, November 8, 2025

Goodbye moon, hello comet

Moonset behind Bristol Head on Friday morning (07 Nov)

 Comet C/2025 A6 (Lemmon) is now setting behind the Bristol Head ridgeline just as astronomical dusk begins (about 6:30 pm MST).  Moonrise on Saturday night (08 Nov) was about 80 min later.  There was just a brief window of time to catch the comet in darkness before it sank out of sight.

The last vestige of twilight.  Rokinon 135mm f/2 lens.

About to disappear.  AT80EDT f/6 refractor.

Comet Lemmon has passed peak brightness and is now about magnitude 4.8.  The tail is still impressive photographically.
 

Wednesday, November 5, 2025

November Full Moon. And the comet.

 The full moon of November is traditionally (Northern Hemisphere) known as the "Beaver Moon".  This year it is also hyped as a so-called "supermoon".  Whatever.  The moment of fullest moon was 6:19 am MST on 05 Nov.

A recent beaver dam.

 
Beaver Moon rising
 


 

AT80EDT f/6 refractor.

Comet C/2025 A6 (Lemmon) is still visible in spite of the bright full-moon sky.

C/2025 A6 (Lemmon).  Rokinon 135mm f/2.


 

The next morning (06 Nov) the waning Beaver Moon was setting behind Bristol Head: