The thin line of Earth's atmosphere and the setting sun.

The setting sun silhouettes an air traffic control tower

View from space of the Sun setting over Earth's horizon.

Layers of Earth's atmosphere, brightly colored as the sun sets over South America.

Solar activity on the Sun.

Solar activity on the Sun.

Solar activity on the Sun.

Solar activity on the Sun.

Solar activity on the Sun.

Magnetic field lines on the Sun.

Two solar prominences erupt from the Sun.

A massive X-class solar flare erupts on the Sun.

Setting sun over harvested field, Gleichen, Alberta, Canada.

A UH-60L Black Hawk helicopter silhouetted by the setting sun.

Rays from the setting sun shining on an anemone with a pair of clownfish.

Sea Based X-band Radar dome modeled by the setting sun at Pearl Harbor naval shipyard.

Earth, moon and the sun.

A cutaway view of the sun.

Red dwarf Sun floating through space.

A gigantic UFO venting plasma from the Sun.

Sun movement from Dettah Ice Road, Yellowknife, Northwest Territories, Canada.

Artist's concept of a distant red planet orbiting its Sun.

High dynamic range photo of sundogs and a solar halo around the Sun.

Artist's concept of a Hot Jupiter extrasolar planet orbiting a sun-like star.

Sun setting behind Earth, artwork

Two figures bathing in the sea whilst sipping cocktails with palm trees and a setting sun in the background

Yellow hues superimposed on an image of the sea

Partial view of woman in bikini in tropical setting

An Earth-like planet with an orbiting moon illuminated by a nearby sun.

Illustration of the sun with visible dark sunspots on the surface, prominences and some solar wind.

Artist's concept of an Earth-sized planet passing in front of a sun-like star.

A gas-giant exoplanet transiting across the face of its star.

The hottest known planet in the Milky Way, called WASP-12b, is so close to its sunlike star that it is superheated to nearly 2, 800 degrees Fahrenheit.

Artist's concept of Kepler 444.

A lake of liquid methane on Saturn's giant moon, Titan.

Artist's concept of a Hot Jupiter orbiting a star named 51 Pegasi.

The atmosphere and a setting sun.