Scientists discover a new twist at the edge of solar system
It is so far away that sunlight barely reaches it, making direct observations nearly impossible

For years, scientists have imagined the Oort Cloud as a vast, icy shell surrounding our solar system. It marks the boundary between us and deep space, a mysterious region filled with trillions of frozen objects. But a new study suggests this faraway cloud might not be as simple as we thought.
Astronomers from the Southwest Research Institute in Colorado have uncovered a fascinating detail: the inner part of the Oort Cloud might have a spiral structure. Similar to the arms of our Milky Way galaxy, this spiral shape changes how we understand this distant region.
The Oort Cloud sits between 10,000 and 100,000 times the distance between Earth and the Sun. It is so far away that sunlight barely reaches it, making direct observations nearly impossible. However, scientists can study it by tracking long-period comets — icy visitors that get knocked into the inner solar system by the pull of our galaxy's gravity, known as the "galactic tide."
Using NASA's Pleiades supercomputer, researchers analyzed these comets and found that the inner Oort Cloud is not just a flat disk, as previously thought. Instead, it appears to be a slightly twisted spiral, stretching 15,000 times the distance from Earth to the Sun.
This spiral may have existed for billions of years, shaped by the gravitational forces of our galaxy.