An expedition ship broke free from its moorings and hit another vessel during windy conditions in Ushuaia, Argentina.

At the farthest edge of the Sun’s influence, the Voyager probes have stumbled into something that sounds almost mythic: a sheath of gas heated to tens of thousands of degrees, a kind of invisible ...

At the ragged frontier where the Sun’s influence gives way to the galaxy, a decades‑old spacecraft has stumbled into a ...