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[Music throughout]TESS, the

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Transiting Survey Satellite, has completed its survey of the northern sky,

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marking the end of its primary mission. To do this,

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TESS divided the northern sky into 13 sectors, and its four cameras

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monitored each sector for nearly a month. With

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these extended views, TESS looks for slight dips in starlight when

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distant planets pass in front of their host stars. But it

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also caught short-lived events, such as a black hole tearing apart

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a star that wandered too close. It took a full year

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of TESS imagery to build this beautiful panorama of the northern

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sky. The bright band to the left is the Milky Way, our home

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galaxy viewed edge on. A large swath

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of the northern sky remains unmapped. For six sectors,

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TESS tipped its cameras further north to avoid regions where stray light from the Earth

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and the Moon would hamper the view. At the center

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is the continuous viewing zone. Here the view of one 

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TESS camera overlaps across all 13 sectors,

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which means TESS monitored the region for nearly an entire year.

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At its center is the north ecliptic pole. This is

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where the imaginary axis of Earth’s orbit around the Sun meets the sky.

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More familiar to sky watchers is the north

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celestial pole. This where the north end of our planet’s spin axis

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intersects the sky. The whole starry vault appears

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to revolve around this point, conveniently marked by the nearby 

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star Polaris. To find Polaris, follow a line

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set up by these two stars in the cup of the Big Dipper.

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It’s an easily recognized star pattern that forms the central part of the 

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large constellation Ursa Major.

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Folloing the arc of the Big Dipper’s handle leads to another prominent star,

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Arcturus. Located about 37 light-years

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away in the constellation Boötes, Arcturus is the fourth-brightest

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star in the night sky.

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New stars form in gas-rich clouds throughout our galaxy.

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The North America Nebula, named for its resemblance to the 

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continent, is a prominent example. Located about

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1,700 light years-away in the constellation Cygnus, it's

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part of a vast factory complex with enough gas to make

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100,000 Sun-like stars.

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Peering beyond the confines of our own galaxy, TESS imaged

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the closest neighboring spiral galaxy. Visible by eye

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as a hazy patch, the Andromeda Galaxy, located 

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2.5 million light years away, is a city of stars

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as vast as our own Milky Way.

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Astronomers have just begun sifting through the torrent of TESS data

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and are working to confirm planets among the thousands of candidates

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identified by the mission so far. TESS has already

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found a few northern stars hosting planets. One, named

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HD 191939, possesses a trio of Neptune-size

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worlds. Having successfully mapped about

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75% of the sky during its primary mission, TESS

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is now working on extended duty. Its cameras have turned back

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to the southern sky to complete another yearlong survey,

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which will include areas not mapped the first time around.

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Now improved to return even more data than before,

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the best of TESS is yet to come.

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[Music]

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[Music]

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Explore: solar system & beyond

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NASA