StarDate

A planet orbiting a dead star 750 light-years from Earth is a real lemon. The planet is shaped like a lemon – a result of the extreme gravity of its parent star.

The system is PSR J2322-2650. The star is a pulsar – the crushed corpse of a once mighty star. It’s heavier than the Sun, but only about as wide as a small city. It spins almost 300 times per second, beaming o...

The Sun belongs to a rare class of stars: Class G. Members of this class account for only seven or eight percent of all the stars in the Milky Way Galaxy.

A star’s class is determined by its surface temperature, which we see as its color. G stars are in the middle of the temperature scale, so they shine yellow or yellow-white.

Most class-G stars are in the prime...

Under a dark sky, far from city lights, the eye alone can see thousands of stars. They come in a variety of brightnesses and colors. Yet only a few of those pinpoints are like the Sun.

Stars are classified based on their surface temperature, which is indicated by their color. Hot stars are blue and white, while cool stars are orange and red. The Sun is in the middle, s...

To borrow from an advertising campaign, Jupiter is “getting the red out.” Its enormous “eye” – the Great Red Spot – has been shrinking. It’s now just a third as wide as when it was first seen, and it’s getting smaller all the time.

The Great Red Spot is one of the most recognizable features in the solar system. But scientists still don’t know that much about it. They d...

The Moon anchors a prominent triangle in tomorrow’s early-morning sky. The pattern is well up in the east at first light. The stars Pollux and Castor – the twins of Gemini – line up to the upper left of the Moon, with Mars to the upper right. The brilliant planet Jupiter stands well below the triangle.

Mars and Pollux are almost exactly the same brightness right now. A...