Why is RJX J185635-375 so cool and so dim? Previously, this compact star held claim to being the closest neutron star -- only 150 light-years away. Now new observations and analysis indicate not only a cool temperature for RXJ J185635-375, pictured above, but also a larger distance: roughly 450 light-years away.

Neutrinos, along with things like electrons and quarks, are fundamental pieces of matter according to physicists' Standard Model. But neutrinos are hard to detect. Readily produced in nuclear reactions and particle collisions, they can easily pass completely through planet Earth without once interacting with any other particle.