Old Moon in New Moon’s Arms

The phenomenon where the dark portion of a crescent moon is faintly illuminated by sunlight reflected from Earth.

Visual Description

The thin crescent moon displayed beautiful earthshine, where the dark portion of the lunar disk was softly illuminated by sunlight reflected off Earth’s clouds and oceans. This “old moon” glow in the “new moon’s arms” created a complete lunar disk visible to the naked eye, with the bright crescent contrasting against the dim gray earthshine.

Notable Features

• Bright crescent moon with visible earthshine
• Dark portion of moon faintly visible
• Best seen during waxing crescent phase
• Phenomenon caused by reflected sunlight from Earth
• Most dramatic shortly after new moon

Notes

• Also known as “earthshine” or “Da Vinci glow”
• Leonardo da Vinci first explained this phenomenon correctly
• Best observed 2-5 days after new moon
• Requires clear skies and low horizon visibility
• Naked eye observation, enhanced with binoculars