Trillions have died in the Earth’s seas. Calcified shields of the dead already make up the white cliffs of Dover. The battle between ball-shaped light-colored single-celled plants — phytoplankton called […]

Today is #EnglishLanguageDay & #StGeorgesDay, as well as @LondonMarathon (no @astro_timpeake though), 4 reasons to say hi #London & the #UK! pic.twitter.com/ZgTkxQ5ooS — Thomas Pesquet (@Thom_astro) April 23, 2017

Congratulations to everyone running the @LondonMarathon today – especially #TeamPrincesTrust Great effort! https://t.co/n0kTLo1xmL — Tim Peake (@astro_timpeake) April 23, 2017

A distinct shape: welcome to the US East coast! Cape Cod seems to point in @CityOfBoston’s direction https://t.co/pphJyXGp6H pic.twitter.com/IB05Q3rGrB — Thomas Pesquet (@Thom_astro) April 23, 2017

Far away from the human eye, the Sahara hides marvellous natural wonders. #EarthArt https://t.co/tfulUMRCQB #Proxima pic.twitter.com/RpDwsLFjAW — Thomas Pesquet (@Thom_astro) April 23, 2017

@norrin14 C'est Lake MacKay, #Australia Info: https://t.co/NL6nMi7MUM — ESA (@esa) April 23, 2017

Heading for #EGU2017? Follow @ESA_EO for updates on EO #TownHall with @AschbacherJosef on EO #OpenData https://t.co/xaut2klDTI — ESA (@esa) April 23, 2017

Our week in images https://t.co/NL6nMi7MUM pic.twitter.com/f5Lg8ztNKd — ESA (@esa) April 23, 2017

If you have access to UK TV, @astro_timpeake and others on Earth seen from space #EarthDay2017 https://t.co/DgNSOvtfkz — ESA (@esa) April 22, 2017