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Jupiter-Saturn Conjunction 7' 52"

Posted: 21 December 2020

Open: Sunday, 20 December 2020, 1710 MST
Temperature: 73°F
Session: 1575
Conditions: Mostly clear, breezy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 9mm 100° eyepiece
2" 5.5mm 100° eyepiece
2" 2X Powermate

iPhone 11 Pro Max

1713 MST: LX600 ON, StarLock OFF, High Precision OFF.

1715 MST: viewed Jupiter and Saturn, 7' 48" apart, 102X. Switched to the 2" 5.5mm 100° eyepiece (443X). Both planets were visible in the same field-of-view (FOV). Seeing was not very good however this night.

1721 MST: sunset.

1732 MST: mounted the D850 DSLR at prime focus + 2X Powermate.

1742 MST: viewed Jupiter and Saturn, 12x50 binoculars.

1744 MST: took this iPhone 11 Pro Max photo (0.5X lens) of crepuscular rays in the western sky.


1750 MST: D850 DSLR photo (cropped), prime focus + 2X Powermate, of Jupiter and Saturn (1/125sec, ISO 1600). The four Galilean Moons are visible, two on either side of Jupiter, with the fourth moon faintly visible near the bottom of the image. Very close to the bright moon to the right of Jupiter is the star HIP 99314 that was occulted by Ganymede for some locations at 1757 MST.


1755 MST: removed the camera and viewed the planets, 443X and 271X. Seeing was not good and the planets were too low in the sky for a good view at 443X. It is really unfortunate that the planets are so low in the sky after sunset for this awesome close conjunction.

Mounted the iPhone on the 2" 9mm 100° eyepiece using the Levenhuk smartphone adapter. This image was taken with the iOS app NightCap Camera (ISO 200, 1/100sec, 1X lens).


1821 MST: D850 DSLR photo (f/4, 4 seconds, ISO 1600, FL 70mm) of the western sky showing Jupiter and Saturn over Cassiopeia Observatory. Note the clouds.


1827 MST: viewed the planets, 271X. The four Galilean Moons were visible, as was star HIP 99314. Two moons were visible at Saturn. Using 102X the view of the planets close together was a pretty sight.

1833 MST: LX600 OFF.

Close: Sunday, 20 December 2020, 1838 MST
Temperature: 55°F
Session Length: 1h 28m
Conditions: Mostly clear, breezy

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