Astronomers have found a distant world that challenges planetary formation theory, with a rocky planet where gas giants should be.

The fourth planet in the system is a rocky world, while the second and third ones are gas planets.

We know that our Solar System is not the blueprint for all planetary systems out there. There are gas giant planets orbiting closer to their stars than Mercury, and rocky worlds much larger than Earth ...

Add Yahoo as a preferred source to see more of our stories on Google. A view of HOPS-315, a baby star some 1,400 light-years from Earth where astronomers have observed evidence for the earliest stages ...

Astronomers have uncovered a distant planetary system that flips a long-standing rule of planet formation on its head. Around the small red dwarf star LHS 1903, scientists expected to find rocky ...

Illustration comparing the planets of the Solar System and the Sun on the same scale. The planets are shown to scale relative to each other but their distances are not. From left to right the bodies ...

Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a precious peek into the dawn of our own solar system. It’s an unprecedented ...

To better understand why the planets have variable compositions, we have to first understand the process of how stars form. While the composition of gas and dust in a precursor molecular cloud is ...

Our solar system is a smashing success. A new study suggests that from its earliest period — even before the last of its nebular gas had been consumed — Earth’s solar system and its planets looked ...

Peering through a cosmic keyhole at distant baby star, astronomers may have opened a new window on the deep past of our own solar system. Weighing in at 0.6 solar mass, HOPS-315 should someday grow to ...