AThe "Crab" nebula is an old supernova remnant that is 6500 light years away.

The event Et and Raoul are referring to is called a "conjunction" and it just means two or more objects will "appear" to come very close in the night sky.

The excitement comes from the fact that conjunctions make excellent viewing and photographic opportunities for Amateur Astronomers.

This is an Okay place to learn about space but I suggest a good book on astronomy or cosmology.

Something to try; Figure out how far light travels in one day at 186,000 miles per sec (300,000 km). In a week? IN a month? A year? Then realize the light from M1 has been traveling 6500 years to reach us.