moon phase

[Nirnman]

I know this is not wargaming related but hoping to probe the hive mind to see if anyone can answer a puzzling question?
I am sitting he and noticed the moon is still visible in the sky this morning at 10:30 am GMT. it is a waning half-moon phase and
I for the first time really noticed the Earth's shadow casts a straight line across the moon's disc.
Now as both the Earth and the Moon are spherical why doesn't the shadow cast on the Moon appear as curve (as it does over the Sun during a solar eclipse)
Probably someone will be able to explain this.
It's amazing what little things occur to my mind when I am not involved ibn doing something productive such as painting wargame figures.

[Leon]

Not sure exactly on that, but the shadow/line on the moon is the angle of the sun against it rather than any shadow effect from other objects.  A half moon is only getting half of its surface illuminated by the sun so that should be the only time when the shadow would appear in a straight line.  Any other angle (quarter or almost full moon) and the curvature of the moon itself causes the shadow to become curved.

[sean66]

If you can see the moon during daylight hours.
then the moon the earth and the sun make the three points on a triangle.
that is why the shadow of the moon is straight.
Regards
Sean

[ronan]

[Duke Speedy of Leighton]

Ronan, ce n'est pas une lune!

[Nirnman]

Many thanks for the usual prompt and clear explanations to what was puzzling my idle mind this morning

[steve_holmes_11]

The line is a curve, you are viewing it sideways on.

Another commentator has observed that a moon in daylight means Sun and Moon are within a limited angle of each other.
This means you'll not see the extremes of new of full moon by daylight (Some exceptions for locations very close to the earth's poles, midnight sun and all that).

I remember Patrick Moore extolling the half moon phase (and those close to it).
The very long shadows allowed him with a nice, but amateur telescope set-up, to map out much of the moon's surface.
It is his greatest claim to fame among astronomers, and his knowledge was key to selecting landing sites for the Apollo program.

[ronan]

Ronan, ce n'est pas une lune!

The camo isn't good enough, so ?

[FierceKitty]

If you can see the moon during daylight hours.
then the moon the earth and the sun make the three points on a triangle.
that is why the shadow of the moon is straight.
Regards
Sean

Walter Theresa Friederich?

[d_Guy]

Abbott's  Flatland?

[chrishanley]

To indicate if the moon is waxing or waning there is a little rhyme which goes;
If the white is on the right, it is getting bright.
So referring to the picture of the half-moon earlier in the thread, in about a week it will be a full moon.
Chris