Across
- 2. a cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.
- 4. having or representing the earth as the center, as in former astronomical systems
- 6. relating to the nucleus of an atom
- 7. a flare star in the constellation Centaurus that is the nearest star to the sun
Down
- 1. the process of causing a material or object to melt with intense heat so as to join with another
- 3. a star of relatively small size and low luminosity, including the majority of main sequence stars.
- 5. the solid part of the head of a comet.