A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

There are a couple of ways that scientists can date planets, so which planets formed first in our solar system?

Astronomers have discovered new evidence that suggests the possibility of an unknown planet in our solar system's farthest ...

Astronomers have discovered fresh evidence suggesting the possible existence of an unseen planet in the far reaches of our ...

While Planet Y has been not yet been directly observed, unexpected inclinations found in the orbits of roughly 50 distant ...

The European Space Agency also hoped to observe the interstellar object during its close approach to Mars using two ...

ESA’s Mars orbiters have observed comet 3I/ATLAS, only the third interstellar comet ever discovered. The faint, distant ...

A mysterious space object named 2023 KQ14, nicknamed “Ammonite,” challenges theories about the mysterious and possible Planet ...

Planets that orbit white dwarf stars should be too hot to host alien life, theories suggest. But a new study accounting for ...

In a little less than a year from now, Jupiter and the moon will be part of one of the best celestial highlights of 2026. On ...

From lava worlds to gas giants, NASA says the variety of these worlds is staggering—and that signs of a further 8,000 distant ...

Every one of us is unique and important, but at the same time, we’re a microscopic part of something that’s beyond ...