Looking into the dark
Orbital observatory duo will gaze into the depths of the cosmos
Two major new space telescopes are heading into space this year, beginning with ESA’s Euclid telescope, which will take a deep look into the Universe’s dark side – dark matter and dark energy, that is. While dark matter is the strange substance that holds galaxies together, dark energy is the force that seems to be driving them apart, accelerating the expansion of the Universe. However, even though these dark cousins have been part of our understanding of the Universe for decades, we don’t really know what they are.
Euclid will help astronomers understand these mysterious forces by surveying billions of galaxies, the light of which has taken over 10 billion years to reach us. Covering one third of the extragalactic sky beyond the Milky Way, astronomers will be able to use Euclid data to create a map of galaxies through cosmological time, showing how the Universe has expanded and grown. With this tool in hand, it is then possible to backtrack to gain an insight into how dark matter and energy shaped the cosmos around us.
Then, in the last quarter of the year, the Chinese space agency will launch Xuntian (meaning ‘survey the heavens’). The telescope is similar to the aging Hubble Space Telescope in many ways – its mirror is two metres wide, it images in the visible and near-ultraviolet, and it is designed to be multipurpose – but its cameras have 300 times the resolution of its predecessor. Xuntian will fly in the same orbit, though separate from, the recently completed Tiangong Space Station, and will be able to dock for repairs and upgrades, meaning it could operate long past its initial decade lifespan.