NASA’s Solar Dynamics Observatory captured this image of Earth and the Moon transiting the Sun together on September 13, 2015. The edge of Earth, visible near the top of the frame, appears fuzzy because Earth’s atmosphere blocks different amounts of light at different altitudes. On the left, the Moon’s edge is perfectly crisp because it has no atmosphere. This image was taken in extreme ultraviolet wavelengths of 171 angstroms. Though this light is invisible to our eyes, it is typically colorized in gold.