Space-type autism

3. A small Solar System body with either a perihelion or a semi-major axis between those of the outer planets
8. A moment in time used as a reference point for some time-varying astronomical quantity
10. A line running north–south across the sky
11. The vast, bubble-like cavity in the interstellar medium which surrounds and is created by the plasma emanating from the Earth's Sun
13. A neutron star that puts out pulses of radio energy
15. The surface velocity at which the centrifugal force generated by a rapidly spinning star matches the force of Newtonian gravity

1. Of or relating to a star or star system
2. A concentration of mass formed out of the contraction of a collapsing interstellar cloud
4. The distance in space at which an object would subtend a parallax angle of 1 arc second from Earth
5. A German scientist who used Tycho Brahe's observations of planetary motions to devise three empirical laws
6. A relatively small, icy body that displays extended features when it approaches the Sun
7. The entirety of space and time and their contents
9. The scientific study of the origin, evolution, and eventual fate of the Universe
12. A distant, point-like energy source originating from a powerful active galactic nucleus
14. A huge collection of stars