Hale-Bopp and the Plateau de Bure Interferometer
15.04.1997

Comet Hale-Bopp is being observed by many different telescopes. Here the comet is pictured behind the array of radio telescopes which compose the Plateau de Bure Interferometer. These telescopes are being used to detect the presence of different molecules in the coma and tail of Comet Hale-Bopp.

Retrograde Mars
13.06.2010

Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun.

Star Size Comparisons
22.02.2011

How big is our Sun compared to other stars? In a dramatic and popular video featured on YouTube, the relative sizes of planets and stars are shown from smallest to largest. The above video starts with Earth's Moon and progresses through increasingly larger planets in our Solar System.

Star Size Comparisons
6.06.2013

How big is our Sun compared to other stars? In a dramatic and popular video featured on YouTube, the relative sizes of planets and stars are shown from smallest to largest. The above video starts with Earth's Moon and progresses through increasingly larger planets in our Solar System.

Laguna Starry Sky
27.01.2018

Staring toward the heavens, one of the many lagunas in the Atacama Desert salt flat calmly reflects a starry night sky near San Pedro de Atacama, Chile, planet Earth. Cosmic rifts of dust, star clouds, and nebulae of the central Milky Way galaxy are rising in the east, beyond a volcanic horizon.

Fifth Moon Discovered Orbiting Pluto
16.07.2012

A fifth moon has been discovered orbiting Pluto. The moon was discovered earlier this month in images taken by the Hubble Space Telescope in preparation for the New Horizons mission's scheduled flyby of Pluto in 2015.

The Solar Wind Emerges
8.02.1999

Winds of fast particles blow out from the Sun, but why? Astronomers came a step closer to answering this question recently by making detailed observations of the high-speed wind source with the space-borne Solar and Heliospheric Observatory (SOHO).

Olympus Mons on Mars: The Largest Volcano
15.09.1997

The largest volcano in the Solar System is on Mars. Olympus Mons rises 24 kilometers high and measures 550 km across. By comparison, Earth's largest volcano, Mauna Loa in Hawaii, rises 9 km high and measures 120 km across.

The Sun Sets on Comet Hyakutake
28.04.1996

Comet Hyakutake is seen here just as the Sun sets on April 22. As April draws to a close, Comet Hyakutake will be visible only just after sunset and will be hard to discern against the brightly lit sky.

Asteroid 253 Mathilde's Large Craters
1.07.1997

You're zipping through the Solar System when you pass ... asteroid 253 Mathilde. This actually happened to NASA's NEAR spacecraft just last Friday. The above picture of the previously unresolved asteroid was released just yesterday.