Often we can see the rest of the Moon as well as the white crescent. This is always for a few days just before or just after the New Moon just before sunrise or just after sunset. It is known as Earthshine or the ‘Da Vinci glow’ because Leonardo da Vinci researched and solved the phenomenon in the 16th Century.
If you were standing on the Moon at the time of a new or crescent Moon you would see a Full Earth. Just as the Full Moon illuminates our landscape here on Earth at the time of Full Moon, the Full Earth illuminates the landscape of the Moon and this is what we’re seeing when we see the Moon’s surface at the crescent Moon.
Light from the Sun shines onto the Earth then reflects onto the Moon on either side of the New Moon