The Nemesis theory states that a companion star to the sun passes through it every 26 million years, disrupting it and sending it subjects towards the solar system. Current theories regarding its formation cite gravitational interactions of planetesimals with gas giants, flinging the former out into wide elliptical orbits. Its inner disk ends at the Kuiper belt's ecliptic. Almost a light year in radius, for 10 points, name this still-theoretical 
The Nemesis theory states that a companion star to the sun passes through it every 26 million years, disrupting it and sending it subjects towards the solar system. Current theories regarding its formation cite gravitational interactions of planetesimals with gas giants, flinging the former out into wide elliptical orbits. Its inner disk ends at the Kuiper belt's ecliptic. Almost a light year in radius, for 10 points, name this still-theoretical cloud surrounding the solar system believed to contain several times the Earth's mass in comets, named for a Dutch Astronomer.
The Nemesis theory states that a companion star to the sun passes through it every 26 million years, disrupting it and sending it subjects towards the solar system.
{Oort Cloud}