Far away: Image depicts the distance of the Oort Cloud from the Solar System using a logarithmic scale.
Credit: NASA
Other techniques
Other methods to detect the cloud, such as observing how Oort Cloud objects passing in front of stars cause their light to dim, could provide evidence of larger debris, but the CMB method is the best technique to find smaller objects, the researchers said.
Astrophysicist Geraint Lewis from the University of Sydney said there were a lot of unknowns built into the research. "If the Oort Cloud is effectively spherical, there wouldn't be distortions to the CMB that we could recognise," he said.
But he added that finding the Oort Cloud by any method would be hard work. "We have this large population of cold dark things on the edge of the Solar System. There has to be some sort of reservoir there, but we don't know where it starts, where it ends or [the composition] of the objects."
