There are a couple of ways that scientists can date planets, so which planets formed first in our solar system?

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers had put it forward as an explanation for Uranus’s orbit ...

A coronal mass ejection on another star has been witnessed in its entirety for the first time, revealing that when these violent outbursts take place on young stars, they pack enough energy to potentially kickstart the chemistry of life on any orbiting planets.

Mercury reaches its greatest eastern elongation on October 29, appearing farthest from the Sun in the southwestern sky, offering a brief window for observation after sunset.