Molecules/Matter & Energy

Detecting gunshot residue, free-falling through sand and thinning blood magnetically in this week's news

Signs of shooting

Spiking ammunition with tiny metal-containing compounds could help detect gunshot residue, scientists propose. Standard techniques for revealing whether a shot was fired rely on detecting lead, but the introduction of lead-free ammunition in recent years has stymied those techniques. Researchers in Brazil who tested spiked ammunition report that the little metal complexes glowed brightly under UV light, revealing residue on the shooter’s hand, clothes, gun and the target surface.