Nasa astronaut Matt Dominick aboard the space station captured this waxing lunar crescent illuminated by sunlight. The Moon’s dim glow, caused by earthshine, occurs when sunlight reflects off Earth onto the Moon. Scientists study Earth’s brightness, or albedo, using this phenomenon. The photo also reveals Earth’s atmospheric layers, including the orange troposphere near the surface and the thicker, light-blue stratosphere above. (Credit: Nasa)
