Luckily, there are some rocks left over from our earliest days, asteroids formed during our solar system's birth. It's an old lakebed, and so the sand has been blown away, like right now, and it's exposing the rocks that are on the ground. Some of the rarest are pieces of the moon, blasted here after impacts there.
Occasionally, some of them drop in on Earth, and when they do, they're called meteorites. And you're just looking for something that looks a little bit different. But one of the coolest things about meteorites is that most were formed four-and-a-half-billion years ago, during the birth of our solar system, when, for reasons not yet known, a cloud of gas and dust was transformed into a sun with circling planets.
Desch thinks something gentler triggered the collapse: a shock driven by radiation from a massive star, but Alan Boss has crunched the numbers and insists that at the right distance, a supernova shockwave would be transformed from a destroyer, into a creator. Important because it will help us get a handle on when we left Africa, our ancestral home, and spread out into colder regions.
We believe that our own solar system was a cloud, sitting there in space, more or less minding its own business, when a supernova shockwave struck the cloud and had it collapse down and form a new star system. The earliest clues are bone sewing needles dating as far back as 40,000 years ago, but we know early humans were world travelers long before that.