Because the Earth is doing the work of increasing the Moon's momentum, the Earth's rotation slows down in turn, as its momentum goes to the Moon. To put it another way, as the Moon's orbital momentum ...

Astronomers observe for the first time the actual motion of spirals in a protoplanetary disk, revealing gravitational ...

When you look at the solar system, you might notice that the planets' orbits are tilted, and oddities in the protoplanetary ...

Visualizing our solar system is one of those third-eye treats that never grows old. The Sun and its gravitationally bound planets, asteroids, etc. are in constant relative motion, and thinking about ...

The Sun's counterclockwise rotation (as viewed from its north pole) originates from the initial spin of the solar nebula, a remnant of the larger cloud from which it formed. The direction of this spin ...

I've been wondering this for quite a long time. Why do the planets of our solar system all orbit the sun in (more or less) a single plane? Is it a random coincidence, or are there physical forces that ...

A planet's year length depends on its distance from the Sun. Planets closer to the Sun have shorter years. A planet's rotation speed is unrelated to its year length. Planets' orbital speeds vary ...

Four exoplanets, each larger than Jupiter, orbit HR8799, represented by the yellow star shape at the center. Image: Gizmodo/Jason Wang/Northwestern University Astronomical phenomena tend to occur over ...

Astronomers have made the first measurement of spin-orbit alignment for a distant 'super-Jupiter' planet, demonstrating a technique that could enable breakthroughs in the quest to understand how ...

We tend to assume that planets orbit stars on more-or-less circular paths, but that’s not always the case – even Earth swings into a more oval orbit every now and then. But that’s got nothing on HR ...