As Nasa prepares to launch Artemis II, are the risks of space flight worth the rewards?

The Observer’s former science editor on the unlikely primatologist who made one of the 20th century’s most important biological observations

The first passenger rail journey, from Stockton to Darlington, took place 200 years ago this week. After HS2, it’s a badly needed reminder of what Britain can build

Carbon dioxide may have caused the climate crisis, but a new study argues it is also the ‘miracle molecule’ that made Earth habitable

Hampered by delays and cancellations, confidence in the high-speed rail line couldn’t be lower, according to Sally Gimson’s book

The words of the co-pilot who dropped the atomic bomb on Hiroshima still echo 80 years on. Could the devastation it wrought ever be justified?