A few days ago, the thin crescent Moon passed close to the planet Venus in the evening twilight sky. Conjunctions such as this repeatÂ at roughly one-month intervals so this is not a rare occurrenceâ€”just a beautiful one.
The crescent Moon is ~2.4%Â illuminated by the direct light of the Sun; the remainder of the Moon is lit by Earthshine which is bright enough to show detail on the shadowed face of the Moon. Leonardo da Vinci explained the phenomenon in the early 16th century when he realized that both Earth and the Moon reflect sunlight at the same time. Light is reflected from Earth to the Moon and back to Earth as earthshine.
As mentioned in the previous post, the planets Venus and Mercury passed very close to each other in the evening twilight sky a few nights ago. In fact, this conjuction is the closest conjunction of these two planets until 2033. I chose to photograph the two planets the night before closest approach as I was interested in getting a bit of separation of the two in both the sky and their reflections in the water.
The first image was taken at 2025 MST 27 May 2021 with an 85mm focal length. The second image was taken a short time later at 2035 MST with a focal length of 120mm.
In the first image, there is a very nice and long reflection of Venus in the water; the reflection of Mercury is also present but is faint and diffuse. In the second image, the planets were just a few minutes away from dropping below the ridge to the northwest. In this image, the reflections of both planets are easily seen.
The weather cooperated nicely with light winds allowing reflections on the smooth water of Upper Lake Mary.
Yesterday (12 May 2021) provided an opportunity to view the thin crescent Moon very close to the planet Venus. Also visible in the evening twilight sky was Mercury higher above the pair.
For a few months each year, it is possible to be located so that the setting of the 1-day old crescent Moon aligns along the length of Upper Lake Mary. This allows for a long fetch of water in which to get reflections of the Moon and planets. Of course, this only works if it is not windy and spring is our windy season. So it was very nice to have both clear skies and very light winds for this event.
In the above image the crescent Moon is just slightly above and to the left of Venus. Near the top center of the image is Mercury. Venus is still rising higher in the sky each day while Mercury is dropping lower. Later this month they will pass by each other with ~0.4Â° of separation. That should be another interesting event to photograph.
A recently discovered comet is now shining brightly in the morning sky. Comet C/2020 F3 (NEOWISE) was first spotted March 27, 2020, by NASA’s NEOWISE space-borne telescope. The comet passed inside Mercury’s orbit on 03 July 2020 and quickly brightened as it as heated by the intensity of the Sun.
The comet has been rising around the start of Astronomical Twilight when the eastern horizon is just beginning to brighten. Within about 45 minutes to an hourâ€”or shortly after the start of Nautical Twilightâ€”the morning sky has become bright enough to make observation difficult.
The image above was taken as the comet rose above Grand Canyon. Also visible in the image are the planet Venus, the bright star Aldebaran, and the HyadesÂ and Pleiades star clusters.
By the third weekÂ middle of July the comet will shift from the morning sky into the evening twilight sky. Again, there will be a short window of time in which it is easily observed but viewing the evening is far easier than the morning.
Although it’s fun to photograph the Full Moon, I actually prefer photographing a thin crescent Moon, usually just a day or two after the New Moon. The thin crescent is brightly lit while the remainder is softly lit by light reflected by Earth, hence known as Earthshine. It’s also known as DaVinci Glow. As well, the Moon does not overwhelm the night sky so that stars can also be in the photograph.
During late Spring and into early Summer the crescent Moon sets in the west-northwest and this makes it a good target for shooting at Upper Lake Mary. The long and narrow lake is aligned WNWâ€“ESE so that the Moon casts a brilliant reflection that can run the length of the lake.
I’ve shot this several times over the last few years but never tire of it. All it requires is enough of a gap in the clouds for the Moon to shine and for light winds so that the lake surface is relatively smooth.