White dwarfs slow down their ageing

The stars could still be burning hydrogen in their outer layers

Ice giants’ secret ammonia stash

Uranus and Neptune may be hoarding ammonia deep within their atmospheres

News in brief

A brief roundup of the latest astronomy news

BepiColombo’s first images of Mercury

The mission will have five more flybys before entering orbit

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Cutting Edge: Lewis Dartnell

Getting under Europa’s skin

Cutting Edge: Chris Lintott

Measuring the mass of the Milky Way

Inside the Sky at Night

Neptune and Uranus could help solve the mysteries of planet formation

Interactive

Emails – Letters – Tweets – Facebook – Instagram – Kit questions

What’s on

We pick the best live and virtual astronomy events and resources this month