Stargazers will be treated to a dazzling six-planet "alignment" this January.

The Sun is about 100 times wider than the Earth and the Earth could fit into the Sun over one million times. It would take 500 years for the fastest person on Earth to run the distance from the ...

For the two-layer model, we demonstrate the utility of contours on the mass–radius diagrams. Given the mass and radius input, these contours can be used to quickly determine the important physical ...