Overall, about 1 kg of material is escaping our atmosphere every second. Every day, around 90 tonnes of material escapes from our planet’s upper atmosphere and streams out into space. Although missions such as ESA’s Cluster fleet have long been investigating this leakage, there are still many open questions. How and why is Earth losing its atmosphere?
In a Hubble Space Telescope survey of 2,753 young, blue star clusters in the neighbouring Andromeda Galaxy (M31), astronomers have found that M31 and our own galaxy have a similar percentage of newborn stars based on mass. The intensive survey was a unique collaboration between astronomers and “citizen scientists,” volunteers who provided invaluable help in analysing the mountain of data from Hubble.