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Comet Pons-Brooks, Moon, Supernova 2024ggi

Posted: 16 April 2024

Laurraine and I left home on Tuesday, 26 March 2024, to travel to my southern Indiana hometown where I was the Keynote Speaker at their Eclipse Festival. See my report of the Total Solar Eclipse. While we were gone there were some rainshowers: Tuesday, 26 March, 0.14"; Sunday, 31 March, 2.08"; and Monday, 1 April, 0.32". We returned home on Thursday, 11 April. The sky was clear, but I was too tired from the trip to open the observatory. Saturday, 13 April, I attended a special star party at Oracle State Park. Click the link to read about it.

Sunday, 14 April, was mostly clear but windy; did not open the observatory. Monday, 15 April, I went to the observatory to remove two of the bungee cords I had purchased in 2021 for the Dome Cover. These cords are on the south side of the observatory and had dramatically deteriorated due to the Sun. The other four original cords are still OK.


I will be getting these replacements from Amazon since my local hardware stores no longer carry the proper length cords.

Open: Monday, 15 April 2024, 1813 MST
Temperature: 75°F
Session: 1951
Conditions: Clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 30mm eyepiece
12x50 binoculars

iPhone 15 Pro Max

1824 MST: Dome Cover OFF. It has been on since before I left on the eclipse trip in March.

SYNCed the observatory clock to WWV time signals.

1855 MST: Sunset.

1857 MST: LX600 ON, StarLock OFF, High Precision OFF.

1900 MST: Viewed Jupiter, 102X. No moons were visible in the bright twilight sky.

1909 MST: The Jovian moons Ganymede, Europa, and Callisto were now visible in the twilight sky, 102X.

1912 MST: The Jovian moon Io was now visible, having completed a transit of the planet's disk, 102X.

1921 MST: Wi-Fi ON.

Used SkySafari 7 Pro on the iPhone 15 Pro Max to GOTO Comet 12P/Pons-Brooks, low in the western sky. It was not visible in the telescope eyepiece or finderscope in the bright twilight sky.

1932 MST: Comet 12P (head only) was now visible in the telescope, 102X. Switched to the 2" 30mm eyepiece (81X), hoping to be able to photograph the comet before it was too low and behind nearby trees.

1935 MST: Wi-Fi OFF.

Attached the LiDAR Cover on the iPhone and mounted the iPhone on the 30mm eyepiece using the Accuview 3-Axis Smartphone Adapter.

1943 MST: StarLock ON.

1950 MST: iPhone image of Comet 12P/Pons-Brooks, afocal 81X, StarLock autoguided, taken with NightCap Camera (Long Exposure, ISO 8000, 1sec, 1 minute, 1X lens).


1952 MST: StarLock OFF. The comet was now behind tree limbs.

1953 MST: Viewed Comet 12P/Pons-Brooks, 12x50 binoculars. Only the head and coma were visible.

2000 MST: Slewed to the Moon. With the iPhone still mounted on the 30mm eyepiece, took this iPhone image of the Moon using NightCap Camera (ISO 65, 1/2400sec, 1X lens).


Removed the iPhone and switched to the 2" 24mm eyepiece. Viewed the Moon, 102X.

2007 MST: High Precision ON.

Slewed to NGC3621 (galaxy), low in the southern sky, with the hope of viewing the recently discovered Supernova 2024ggi. The galaxy was faintly visible, 102X, in the bright moonlit sky, but the supernova was easily seen.

Mounted the D850 DSLR at prime focus, focused on the star Minkar, and locked the 12" primary mirror.

2028 MST: StarLock ON.

My first image (5 minutes, ISO 5000) was overexposed due to the bright moonlit sky.

2040 MST: NGC3621 (galaxy) and Supernova 2024ggi, StarLock autoguided, 2 minutes, ISO 3200.

Mouseover or tap on image
Mouseover or tap on image for supernova marker

2043 MST: StarLock OFF.

Viewed NGC3621 and the supernova, 102X.

2050 MST: LX600 OFF.

It was nice to be back in the observatory after three and half weeks.

Close: Monday, 15 April 2024, 2057 MST
Temperature: 52°F
Session Length: 2h 44m
Conditions: Clear

Pluto now Arizona’s official state planet.

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