NASA has released a new panorama of the northern sky, courtesy of its Transiting Exoplanet Survey Satellite (TESS). This mosaic is assembled from 208 images taken during TESS’s second year of science operations, completed in July.
The mission split the northern sky into 13 sectors, each of which was imaged for nearly a month by the spacecraft’s four cameras.
The northern mosaic covers less of the sky than its southern counterpart, which was imaged during the mission’s first year of operations.
For about half of the northern sectors, the team decided to angle the cameras further north to minimise the impact of scattered light from Earth and the Moon. This results in a prominent gap in coverage.
But there is plenty to see. Among the many notable celestial objects are the glowing arc and obscuring dust clouds of the Milky Way (left), the Andromeda galaxy, our nearest large galactic neighbour 2.5 million light-years away (oval, centre left), and the North America Nebula (lower left).
TESS locates planets by simultaneously monitoring many stars over large regions of the sky and watching for tiny changes in their brightness. When a planet passes in front of its host star from our perspective, it blocks some of the star’s light, causing it to temporarily dim. This event is called a transit, and it repeats with every orbit of the planet around the star.
The mission has discovered 74 exoplanets beyond our solar system, and NASA says astronomers are sifting through 1200 other potential candidates; 600 of these lie in the northern sky.