The Lunar X, 2021
This image of the moon was
May 18, 2021,
from Maple Shade, NJ. It was taken at 8:12 pm EDT (the same time as
sunset) with a Canon EOS RP mirrorless digital camera and a Tamron 150
to 600 mm, f/5 to 6.3 telephoto zoom lens (set to 600 mm focal length)
on a fixed tripod.
the setup (taken with my iPhone). It was exposed 1/1000 second at f/8.0, ISO 4000,
daylight white balance, then mildly adjusted in Canon's Digital Photo
Professional 4 and cropped to about 30% of the original linear
dimensions, providing a field 1.0° wide x 0.75° high. Mouseover for
Phil Harrington's predictions for 2018 to 2023
are tabulated here.
The Lunar X, 2018
Here's a single frame
snapshot of the gibbous moon taken at 10:46 pm EDT on
May 24, 2018
(3 days after first quarter at 11:49 pm on May 21, 2018), with a Canon 7D Mk II digital SLR camera at the 910 mm prime focus of a
Stellarvue 130 mm, f/7 apo refractor. It was exposed 1/1000 second at
ISO 400, then converted to monochrome and cropped to about a third of
the sensor's area yielding a field about 0.6° square. It wasn't a
specific target when I took the picture, but when I examined it closely,
I noticed the Lunar X
was visible, although not nearly as prominent as when it appears as a
highlight at the terminator. Mouseover for a label.
Here's an crop
of the image above to better show the "X" (mouseover for a label).
Unfortunately, I do not have ready access to the original image for a
better cropped view, as opposed to this cropping of an already-cropped
and resized image.
The Lunar X Challenge
Here's a detailed image of
the Moon from the Astronomy Picture of the Day for
January 16, 2023. Can you spot the Lunar X? It's not too far from
Rupes Recta (the Straight Wall). It's visible on this
reduced-size version, but here's a
full-resolution version if you prefer.