An aurora is a luminosity that occurs at high altitude, and generally above 60 ° latitude, although it is also observed in other areas. As it occurs in the northern or southern hemisphere, it is called aurora borealis or southern aurora. The term polar aurora applies in both cases. The aurora consists of rapidly changing spots and luminous columns, of various shades.

The Gizmodo article A Visiting Star Jostled Our Solar System 70,000 Years Ago refers to the the three year old ApJ. paper The Closest Known Flyby of a Star to the Solar System (also arXiv) which

Could there be another planet between Mercury and the Sun? Kepler found a lot of planets orbiting its star even 20 times closer than Mercury. If there were such planets in our system - would it be

If there were two Earth-like planets in a tight orbit around each other, how close could they be to each other without colliding? How quickly would they have to orbit to be stable? Would they be

Planet Jupiter, an old gas giant Jupiter is the largest planet in the Solar System. It has almost two and a half times the matter of all the other planets together, and its volume is 1,317 times that of Earth. Of the so-called outer planets or gas giants, Jupiter is the one that is closest to the Sun.

Could it be possible to detect exoplanets that have an abundance of iridescent minerals by analyzing their star's spectra over time as the angle in observation would lead to changes in absorbed