Starship Asterisk*

Crescent Moon Beyond Greek Temple

Explanation: Why is a thin crescent moon never seen far from a horizon? Because the only geometry that gives a thin crescent lunar phase occurs when the Moon appears close to the Sun in the sky. The crescent is not caused by the shadow of the Earth, but by seeing only a small part of the Moon directly illuminated by the Sun. Moreover, the thickest part of the crescent always occurs in the direction of the Sun. In the evening, a thin crescent Moon will set shortly after the Sun and not be seen for the rest of the night. Alternatively, in the morning, a crescent Moon will rise shortly before the Sun after not being seen for most of the night. Pictured two weeks ago, a crescent moon was captured near the horizon, just before sunrise, far behind remnants of the ancient Temple of Poseidon in Greece.

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The goddess Selene was hanging out at Poseidon's temple that night ... but not for very long.

Nice bit of astronomical truth about crescent moons never visible high in the sky -- to the naked eye.
Are there no fancy instruments that can see it in the middle of the day near the sun (not at an eclipse) in spite of the light?
Perhaps there is a Guinness record for this: The highest altitude (angular altitude) for a snapshot of the moon at a given crescent phase, or even a completely new moon, lit only by earthshine.

I might not be clear what a "crescent moon" is in english. But if it s an increasing moon after the "new" moon, this text is full of errors !!! ???
And also the picture is from efore the new moon at the end of the decreasing moon, except if the picture is "reversed" which would be pretty stupid for an educational purpose.
My 8years old kid learnt that 2 years ago ...

I m puzzled or not well awakened

Notably, a new crescent moon is only seen in evening closely after the sun set, never in the morning, cause it rises AFTER THE SUN. If it rises before, it s the last quarter of the moon ...

Maybe its a test for APOD readers ...

Corentin wrote: ↑Tue Feb 28, 2023 8:04 am I might not be clear what a "crescent moon" is in english. But if it s an increasing moon after the "new" moon, this text is full of errors !!! ???
And also the picture is from efore the new moon at the end of the decreasing moon, except if the picture is "reversed" which would be pretty stupid for an educational purpose.
My 8years old kid learnt that 2 years ago ...

I m puzzled or not well awakened

A crescent is a crescent. It doesn't matter if the crescent Moon is waxing or waning.

Ann

Ok, thanks, i always find new "false friend" in english

The image is oriented to the east, the temple is also oriented east-west and the temple is to the east (according to google maps)

MarkBour wrote: ↑Tue Feb 28, 2023 7:25 am...Are there no fancy instruments that can see it in the middle of the day near the sun (not at an eclipse) in spite of the light?
Perhaps there is a Guinness record for this: The highest altitude (angular altitude) for a snapshot of the moon at a given crescent phase, or even a completely new moon, lit only by earthshine.

The first amateur astronomer who photographically captured an extremely thin lunar crescent 5.0 degrees from the sun is Martin Elsasser on June 15, 2007.
https://www2.lpod.org/wiki/January_31,_2008
He broke his own record on May 5, 2008, capturing a crescent at 4.58 degrees from the sun and 5 minutes before the New Moon phase.
https://www.mondatlas.de/other/martinel ... 80505.html
On July 8, 2013, Thierry Legault captured the New Moon phase using the same technique, at an elongation from the sun of 4.6 degrees.
http://www.astrophoto.fr/new_moon_2013july8.html
Both used dark IR pass filters.

MarkBour wrote: ↑Tue Feb 28, 2023 7:25 am The goddess Selene was hanging out at Poseidon's temple that night ... but not for very long.

Nice bit of astronomical truth about crescent moons never visible high in the sky -- to the naked eye.
Are there no fancy instruments that can see it in the middle of the day near the sun (not at an eclipse) in spite of the light?
Perhaps there is a Guinness record for this: The highest altitude (angular altitude) for a snapshot of the moon at a given crescent phase, or even a completely new moon, lit only by earthshine.

I've seen the crescent Moon in the middle of the day, perhaps 10 degrees from the Sun, by standing in the shade and using binoculars. It's trivially imaged that close to the Sun. I don't let my telescope point closer than 10 degrees to the Sun, but if I wanted to override that, I'm sure I could capture a crescent well inside that.

Wow! Beautiful photo of the Crescent moon behind the Poseiden
Temple! I love night photos of the Temple; really makes a nice
view!

Beautiful shot!

is it marble?
How can it be the same dusty amber colour as Moon?
Or is it a Na illumination?

VictorBorun wrote: ↑Wed Mar 01, 2023 8:46 am is it marble?
How can it be the same dusty amber colour as Moon?
Or is it a Na illumination?

The temple of Poseidon is made from local soft white marble with light blue hues and that is the cause that it appears white in the daylight. The amber color in the photo is obviously caused by the color temperature of the floodlights. The white balance camera setting I used was "daylight".