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A NASA spacecraft just did a fly-by of the most distant object we’ve ever visited

January 1, 2019

NASA’s New Horizons space probe came to within 2,200 miles (3,500 kilometers) of Ultima Thule, a space rock that lies four billion miles from Earth—and looks to be shaped a little like a peanut.
The news: The fly-by took place at 12:33 EST today, but because New Horizons is so far away  it takes around six hours to send data back to mission control at Johns Hopkins University’s Applied Physics Laboratory. The team delayed the transmission to make sure it didn’t interfere with any observations, so it was a full 10 hours later before the probe could confirm that the mission was a success. The NASA team (led by Alan Stern, pictured celebrating its success above) only had one shot at getting close enough to the rock, since New Horizons is whipping past at 31,5000 miles per hour.
Icy wilderness: The object lies in the Kuiper Belt, a huge area of mysterious chunks of ice and small planet-like objects that lies way beyond Neptune, and a billion miles further on than Pluto. The first fuzzy pictures of Ultima Thule show that it seems to be spinning and is about 22 miles long by nine miles wide. There’s even the slight possibility that it might be two objects closely orbiting one another, although this is considered to be less likely, the AP reported. Its name is an ancient cartographer’s phrase meaning it is "beyond the known world."
Waiting game: Better pictures will come through on Wednesday, but high-quality images won’t arrive until later this month or early in February. It will take almost two years before all of the data can be downloaded. The New York Times has a nice collection of pictures taken of Ultima Thule as New Horizons approached. 
Next steps: The observation of the mysterious object comes 3.5 years after New Horizons gave us our best ever look at Pluto and 12 years since New Horizons launched from Cape Canaveral. The team hopes to get the mission extended and explore more mysterious Kuiper Belt objects in the 2020s. It’s been a busy New Year period for NASA: its Osiris Rex spacecraft just entered orbit around the asteroid Bennu on Monday, too.

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