A brief roundup of the latest astronomy news

Water vapour on moon

A fresh look at archived Hubble data has shown evidence of water vapour in the atmosphere of Jupiter’s moon Ganymede. It’s thought the moon has more water than all of Earth’s oceans, but that most of it is frozen 160km below the surface, and it’s uncertain how the vapour might have made its way to the atmosphere.

Early solar maximum

Solar Cycle 25 is heating up faster than expected. Sunspot numbers from July 2021 indicate activity could reach a maximum as soon as October 2024, meaning it would peak a few months before the earliest date previously predicted by a panel of experts back in 2019.

Starliner delayed

The second orbital test flight of Boeing’s Starliner astronaut capsule has been delayed again after moisture was found in several of the vehicle’s valves. The test was initially meant to occur in late 2020, but has been beset by delays. NASA hopes to use the Starliner to transport astronauts to the ISS.

Japan heading to Phobos

The Japanese Aerospace Exploration Agency (JAXA) is planning a space mission to bring samples from the Martian moon Phobos back to Earth by 2029. The mission aims to bring back 10g of material, and could also visit Mars’s other moon, Deimos.

Bennu not a threat

Although asteroid Bennu will pass close to Earth in 2135 it is very unlikely to hit us, according to the latest analysis of its orbit using high precision-tracking data from OSIRIS-REx. The spacecraft circled the asteroid from 2018 to 2020, allowing astronomers to significantly reduce the uncertainties in the asteroid’s orbit.

Mid-life stellar crisis

Magnetic fields could cause Sun-like stars to have a ‘mid-life crisis’, when they experience dramatic breaks in their activity and rotation rates. A new study shows the flow of charged particles from the star – the stellar wind – magnetically brakes the star’s rotation, causing it to slow down over billions of years, becoming less active in the process.

IMAGES: NASA/JPL-CALTECH