I HAVE got an observing challenge for you all this week - how young a Moon can you see?
From the weekend the Moon will be visible in the west after sunset, a little higher, brighter and bigger - a slightly bigger crescent - each evening. Everyone calls a thin crescent Moon a ‘New Moon,’ even though a true new Moon is when it's directly between Earth and the Sun so we can't see it at all. So your challenge is to see how thin a new Moon you can find before it becomes obvious...
You should start looking on Sunday evening, scanning the western sky right after sunset, looking for the tiniest sliver of a crescent. Binoculars will help. Monday evening your chances will be better, and Tuesday evening the crescent Moon should be pretty easy to find.
For these first few days of the lunar month, keep a look out for ‘The Old Moon in the New Moon's Arms - that's when the dark part of the Moon's disc can be seen glowing faintly. How? Because sunlight bouncing off Earth's clouds and oceans lights it up. Which is why astronomers call the phenomenon ‘Earthshine.’ It looks best - and beautiful - in binoculars.
Eddington Astronomical Society of Kendal