In a technological first, NASA has made a sip of breathable air on Mars

Well, isn't this a breath of fresh air: An experiment on board the Mars Perseverance rover designed to produce breathable oxygen from carbon dioxide has been switched on and is working! On April 20 it produced 5 grams of oxygen — not a huge amount, but it's designed to make as much as 10 grams per hour, and this is the very first time oxygen has been converted from native air on another planet.

The device is called MOXIE — the Mars Oxygen In-Situ Resource Utilization Experiment — and it's small...