A seismic shift occurred in astronomy during the Scientific Revolution, beginning with 16th-century polymath Copernicus and his proposal that the Earth revolved around the sun. By the 17th century, ...

The planets of our solar system move in ellipses. We've known this, so we are told, ever since Johannes Kepler devised his laws of planetary motion in the early 1600s. While it's true that orbits are ...

Studying the orbits of thousands of exoplanets shows that large planets tend to have elliptical orbits, while smaller planets tend to have more circular orbits. This split coincides with several other ...

It's 2015. You're NASA's chief engineer designing a moonbase for Shackleton Crater at the Moon's south pole. You're also designing a com-system that will allow astronauts constant radio contact with ...

As planetary systems evolve, gravitational interactions between planets can fling some of them into eccentric elliptical orbits around the host star. Smaller planets should be more susceptible to this ...

How does a planet’s size influence its orbit around its parent star? This is what a recent study published in the Proceedings of the National Academy of Sciences hopes to address as a team of ...

This week's question comes from Wilma David in Ottawa, Ontario. David asks: Given that the sun is almost perfectly spherical (not oblate), why do planets orbit the sun in an ellipse? I understand that ...

A: When two spiral galaxies collide, gravity is the main force that comes into play. As the galaxies approach each other, gravitational forces start to pull the stars, gas, and dust of the spiral arms ...

A stronomers using the Hubble Space Telescope (HST) and W.M. Keck Observatory have found a lopsided debris disk around young star HD 15115. As seen from Earth, the edge-on disk resembles a needle ...