The human mind may find it difficult to conceptualize: a cosmic cloud so colossal it surrounds the Sun and eight planets as it extends trillions of miles into deep space. The spherical shell known as ...

Right now we can’t observe extrasolar Oort clouds, if they exist. (Not for lack of trying; we’ve been looking for them since 1991!) In fact, we can’t even directly observe our own Oort Cloud. We can ...

In the farthest reaches of our solar system, beyond the familiar planets and even the icy Kuiper Belt, lies a mysterious ...

The Oort Cloud, an expanse of icy bodies in the far reaches of our solar system, is shown here in a scene from "Encounters in the Milky Way," a show at New York City's Hayden Planetarium that spawned ...

Discover the secrets of the Oort Cloud: astronomers unveil a comet from the inner Oort Cloud with hints about solar system formation. Astronomers have spotted an icy object near Neptune that they say ...

The human mind may find it difficult to conceptualize a cosmic cloud so colossal it surrounds the Sun and eight planets as it extends trillions of miles into deep space. The spherical shell known as ...

Humans generally like stability. We are used to our small, predictable world: Every 24 hours, we rotate on our axis; every 365 days, we revolve around the Sun. We have followed this pattern for ...

Astronomers searching for the faintest glimmers of light beyond distant Pluto say they’ve discovered a new dwarf planet – and that this planetoid’s movements hint that an invisible giant planet ...

The Oort cloud is a region in our solar system's vicinity we don’t know all that much about. Named after Dutch astronomer Jan Oort, it is a theoretical concept comprising planetesimals (solid objects ...

Planet-hunters scouring the heavens have found thousands of distant worlds around other stars, but astronomers may have overlooked one lurking much closer to home. Scientists searching for glimmers of ...

While the Voyager spacecraft are constantly traveling out of the Solar System, sometimes they are getting closer to Earth.