Nasa has approved a new sky survey mission that will explore the origins of the universe and its galaxies and of water in planetary systems.
This comprehensive mission is known as SPHEREx (the spectro-photometer for the history of the universe, epoch of reionization and ices explorer). It will survey the sky in 96 different colour bands that span the optical and near-infrared wavelengths of light.
It will perform multiple surveys, completing an image of the whole sky once every six months, and collecting data on more than 300m galaxies. The distribution of those galaxies will reveal the behaviour of the universe in the moments following the big bang.
SPHEREx will also collect data on more than 100m stars in our own galaxy. This will allow astronomers to look for traces of water and organic molecules – the essentials for life – around those stars.
SPHEREx has been chosen from nine proposals that were submitted to Nasa’s astrophysics explorers programme in September 2016. Eleven months later, Nasa selected two mission concepts for further study, from which SPHEREx has emerged the winner. It was judged most likely to be ready for a 2023 launch and to stay within its $242m (£210m) budget.