Kepler mistakenly believed he had captured Mercury moving in orbit across the sun in May 1607, but he later retracted his ...

Billions of years from now, the Sun will swell into a red giant, swallowing Mercury, Venus, and Earth. But that’s not the ...

In about 5 billion years, the Sun will run out of hydrogen at its core. This will make it swell up into a red giant, as it ...

This month will usher in two separate conjunctions — one between the moon and a rarely-visible Mercury, and another between ...

The following evenings will see fleet-footed Mercury draw level with Jupiter, before rising above and away from the gas giant ...

From Mercury to Neptune ... structured in a roughly flat plane called the ecliptic, with most planets orbiting the sun in the same direction (counterclockwise, as viewed from above the sun's ...

Astronomers announced Wednesday they have discovered a massive planet orbiting a tiny star, a bizarre pairing that has ...

Astronomically, this apparent backward motion is due to Mercury orbiting the sun faster than Earth. As it catches up and passes us, it creates the illusion of moving in reverse. This period can ...