Video: Rosetta scientist Matt Taylor on the end of mission

After completing a dress rehearsal for launch day over the weekend, the four astronauts gearing up for liftoff Thursday on a SpaceX Falcon 9 rocket are in good spirits and spending time with their families in Florida before leaving the planet for a six-month expedition on the International Space Station. Forecasters with the U.S. Space Force’s 45th Weather Squadron predict an 80% chance of acceptable weather for launch early Thursday.

Europe’s Rosetta spacecraft has recorded a brilliant beam of gas and dust shooting into space from Comet 67P/Churyumov-Gerasimenko, the most spectacular such emission since the probe arrived at the tiny frozen world one year ago.

A saucer-shaped entry, descent and landing demonstrator separated from Europe’s ExoMars orbiter Sunday, beginning a three-day approach aiming to become the first European-built craft to set down on the red planet and return data.