More than 15 months after NASA’s New Horizons spacecraft flew past Pluto, the last bit of data captured during the flyby has finally been transmitted back to Earth.
NASA said the final transmission was a digital segment of an observation sequence captured by New Horizons’ Ralph/LEISA imager, focusing on Pluto and its biggest moon, Charon. The readings were stored up on July 14, 2015, as the piano-sized probe zoomed past Pluto about 3 billion miles from Earth. Since then, New Horizons’ distance from Earth has grown to 3.4 billion miles.
The downlink took place at 2:48 a.m. PT Oct. 25 via NASA’s Deep Space Network station in Canberra, Australia. In all, more than 50 gigabits of data relating to Pluto and its moons have been transmitted back to Earth.
Why did it take so long to send back an amount of data that would basically fit on a thumb drive?