NASA Supercomputer Reveals Spiral Structure in Solar System’s Outer Edge

New simulations suggest the inner Oort Cloud resembles a miniature galaxy with two spiral arms shaped by galactic gravitational forces.

The inner Oort Cloud, located 1,000 to 10,000 astronomical units (AU) from the Sun, may have a spiral structure spanning 15,000 AU, according to a new computational study.
This spiral shape, resembling a miniature galaxy, is influenced by the Milky Way's gravitational forces, referred to as the galactic tide, rather than by planetary gravity within the Solar System.
The study used NASA's Pleiades supercomputer to simulate the Oort Cloud's evolution over 4.6 billion years, incorporating gravitational effects from the Sun and the Milky Way.
The findings challenge previous models that depicted the inner Oort Cloud as a flat, toroidal disk, instead showing a stable spiral structure that has persisted since the Solar System's formation.
Directly observing the spiral structure remains challenging due to the extreme distance and faintness of the Oort Cloud, but the model aligns with comet trajectory data and prior research.