Are you behind on your holiday shopping or holding out for some final pre-Christmas bargains? From telescopes to monoculars, we've rounded up the best last-minute savings on optical equipment.
Our middle-aged Solar System is mostly calm and stable, with fully-formed planets staying in their lanes while placidly orbiting the Sun. But it wasn't always this way. The Solar System had a tempestuous youth, full of collisions that shattered many bodies into tiny pieces. The debris-strewn main asteroid belt is evidence of this.

