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Smoky Sky from Arizona Wildfires,
Antennae Galaxies

Posted: 7 June 2021

Monday, 31 May 2021, was cloudy with a brief thundershower (0.02" rain). Cloudy skies continued until Saturday, 5 June. A Red-Flag Warning was issued for high wind on Saturday. Wildfires have already started in Arizona, impacting sky quality as seen in this photograph taken Saturday morning.


Saturday afternoon the sky was still smoky with a strong wind blowing. This GEOS-East satellite shows smoke from two large wildfires that were burning near the northern Pinal County border, about 70 miles north of Oracle. The Telegraph Fire, started on Friday, 4 June, exploded to 25,000 acres in one day due to the strong wind. The Mescal Fire, started on Tuesday, 1 June, had burned 8000 acres by Saturday.


This is a photo of the smoke in the northern sky from Oracle taken at 1735 MST.


By sunset at 1929 MST on Saturday, the smoke was visible in all directions and it was still very windy (almost blew the iPhone out of my hand when I was taking this photo).


Sunday, 6 June, dawned with clear skies and very little visible smoke as the smoke was blowing away from Oracle. The Telegraph Fire had burned 34,000 acres and the Mescal Fire had dramatically increased to 29,000 acres burned by Sunday morning. The wind continued on Sunday, increasing as sunset approached. I decided to go out to the observatory with the hope that the wind would die down after sunset.

Open: Sunday, 6 June 2021, 1900 MST
Temperature: 89°F
Session: 1644
Conditions: Clear, some smoke, windy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece


Relaxed on the bench while waiting for the wind to calm down.

1931 MST: sunset.

I went to a high point on our land to photograph the smoke from the Telegraph and Mescal wildfires in the northern sky.


Returned to the observatory patio bench to wait some more for the wind to calm down.

1950 MST: the wind was calmer now.

1951 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed Venus, 102X, through tree branches. The disk was still essentially a full phase.

Returned to the observatory patio bench to watch the stars come out. It was still windy.

2030 MST: back inside the observatory.

Viewed NGC4038 and NGC4039 (Antennae Galaxies), 102X.

Prepared the D850 DSLR for imaging. Mounted the D850 at prime focus, focused on the star Spica, locked the 12" mirror, and slewed back to NGC4038.

2052 MST: StarLock ON.

Took several StarLock autoguided images of the Antennae Galaxies, 5 minutes, ISO 6400, White Balance 5560K. This is a stack of the best six images for an effective exposure of 30 minutes. The "antennae" are faintly visible to the left of the galaxies.


2134 MST: StarLock OFF.

I did a tour of Deep Sky Objects (DSOs) in the constellation of Ursa Major, 102X: M81 (Bode's Galaxy), M82 (Cigar Galaxy), M108 (galaxy), M97 (Owl Nebula), M109 (galaxy), M40 (stars), and M101 (galaxy).

I then did a tour of DSOs in the constellation of Coma Berenices, 102X: M98 (galaxy), M99 (galaxy), M100 (galaxy), M85 (galaxy), M88 (galaxy), M91 (galaxy), NGC4559 (galaxy), NGC4565 (Needle Galaxy), M64 (Black Eye Galaxy), NGC4889 (galaxy), and M53 (globular cluster).

2208 MST: ended tours.

2210 MST: LX600 OFF.

2222 MST: took a Sky Quality reading and reported the result to Globe at Night.

Close: Sunday, 6 June 2021, 2227 MST
Temperature: 73°F
Session Length: 3h 27m
Conditions: Clear, SQM 21.19

Thanks to everyone who purchased my autobiography, Finding my Way to the Stars. I hope you have enjoyed it. I welcome your comments.

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