Back to Glossary

The Moon

The Moon is Earth’s only natural satellite—a rocky, cratered body about one‑quarter the diameter of Earth, orbiting at an average distance of approximately 384,400 km. It influences tides, stabilizes Earth’s axial tilt, and was formed about 4.5 billion years ago following a collision between Earth and a Mars-sized object.

Source: science.nasa.gov

APODs including "The Moon"

The Great Gig in the Sky

08/09/2017

The Great Gig in the Sky
Image Credit: Rogelio Bernal Andreo / NASA APOD

There were no crowds on the beach at Phillips Lake, Oregon on August 21. But a few had come there to stand, for a moment, in the dark shadow of the Moon. From the beach, this unscripted mosaic photo records their much anticipated solar eclipse. In two vertical panels it catches the last few seconds of totality and the first instant of 3rd contact, just as the eclipse ends and sunlight faintly returns. Across the US those gathered along the path of totality also took pictures and shared their moment. And like those at Phillips Lake they may treasure the experience more than any planned or unplanned photograph of the total eclipse of the Sun.