A 2023 study suggests that the shafts of such abandoned mines could serve as energy-storing gravity batteries. Editor's note: Readers often ask us for follow-ups on memorable stories. What has ...

Cartesian 3D printers were the original. Then delta printers came along, and they were pretty cool too. Now, you can add tripteron printers to the mix. The Tripteron is an odd mix of Cartesian ...