Kuiper Belt, well past the orbit of Neptune (artistic illustration). There may be an undiscovered planet in the outer solar system whose presence is revealed by the strange orbit of objects beyond ...

Six of our cosmic neighbors are expected to line up across the night sky tonight, in what has been dubbed a "planetary parade". Throughout much of January and February, Venus, Mars, Jupiter, Saturn, ...

Between now and then, on 21 January 2025, six of the seven other planets will appear in the sky at once in a large alignment ...