Probably nothing. That is, nothing except a high altitude weather balloon made of a then classified material crashing, later to be recovered by members of the 509th.
But then, it seems to be true that the first press releases from local authorities including the military, reported the finding of a flying saucer.
And there are reports (although now mostly second hand) of men who were there reporting seeing oddly shaped bodies and strange materials.
The base intelligence officer who was tasked with taking the wreckage to another base reports leaving it in an office there and returning a few minutes later to find that the space debris he had brought had been replaced with parts of a weather balloon.
One account of those days comes from Julie Shuster, whose father was the press officer at the Roswell base.
“My daddy didn’t lie. My father saw the bodies, my father saw the craft,” she says. “He saw bodies – large heads, almond shaped eyes… and material that couldn’t be burnt, ripped, cut – anything.”
Well, maybe. But then ..
Is it just a coincidence that aliens have never managed to find an earth-dweller who knows how to operate his own camera properly?
And why, if you have journeyed light years across the unknowable vastness of the heavens, would you confine yourself to a fleeting and ambiguous appearance before a handful of New Mexican ranchers?