Probing Einstein’s relativity

Through the Gravity Probe B experiment, scientists developed cutting-edge technologies on the journey to test gravity.

Web extra: The first test of Einstein’s gravity

Scientists first found evidence that general relativity was correct about four years after Einstein published his theory.

Dead stars and doomed planets

When the Sun dies, it will become a white dwarf surrounded by the decaying remnants of planets, asteroids, and comets. Astronomers are watching similar fates befall dozens of other systems in our galaxy.

Flying in Pluto’s shadow

NASA’s new airborne observatory can travel nearly anywhere, including to the elusive center of a distant planet’s shadow on Earth.

Web extra: See more SOFIA

Whether on the ground or in the air, NASA’s flying observatory is a wonder to behold.

2012 — a historic year for solar eclipses

Two solar eclipses — one total and one annular — and the last transit of Venus until 2117 make this a stellar year for observers.

Web extra: Catch May’s annular eclipse

Find the details about the event for your location.

How robotic telescopes are changing astronomy

Automated observatories run telescopes themselves, allowing astronomers to focus on the results.

Create the ultimate observing charts for free

Professional astronomers count on two websites for vast amounts of reliable data. Now amateurs are discovering how to use them for observing.

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