In 1990, the Voyager 1 spacecraft turned its camera toward Earth and took a famous photo called “The Pale Blue Dot” from 3.75 billion miles away. That image has held the record for the farthest ever taken away from Earth—until now. As Ben Guarino reports for The Washington Post, the New Horizons spacecraft has set a new record, taking an image of objects in the Kuiper Belt while 3.79 billion miles from home.
The Kuiper Belt is a ring of objects between Neptune and the edge of the solar system full of dwarf planets, hundreds of thousands of icy rocks and comets. According to NASA, there may even be an undiscovered planet, "Planet 9," hiding somewhere in the region. But there is still much to learn about these frosty orbs. So, after exploring Pluto in 2015, New Horizons, started on its secondary mission to explore 2014 MU69, a Kuiper Belt Object (KBO), which it should reach in 2019.
As Guarino reports, the space probe currently alternates between active and dormant periods to conserve fuel. On December 5th of last year, it woke up and took a routine image of a star cluster called the Wishing Well to calibrate its camera, the Long Range Reconnaissance Imager (LORRI). Though the process was routine, the simple image officially broke Voyager 1's record. According to a NASA press release, two hours later, it snapped images of KBOs 2012 HZ84 and 2012 HE85, setting yet another record.
“New Horizons has long been a mission of firsts — first to explore Pluto, first to explore the Kuiper Belt, fastest spacecraft ever launched,” says principal investigator Alan Stern, a planetary scientist the Southwest Research Institute in Boulder, in the release. “And now, we’ve been able to make images farther from Earth than any spacecraft in history.”
That record won’t be broken by another probe anytime soon, since New Horizons is one of just a few spacecraft that have ever made the harrowing journey to the edges of our solar system. Voyager 1 shut off its camera the same year it captured the "Pale Blue Dot" image and Voyager 2 shut down its cameras after imaging Neptune in 1989. "It is possible for the cameras to be turned on, but it is not a priority for Voyager's Interstellar Mission," according to NASA Jet Propulsion Laboratory's website. Two Pioneer probes—Pioneer 10 and 11—have also traveled farther away than New Horizons, but NASA lost contact with them years ago. This leaves the exploration up to New Horizons.
“The Voyagers and Pioneers flew through the Kuiper Belt at a time when we didn’t know this region existed,” says Jim Green, director of NASA’s Planetary Science Division, in another press release. “New Horizons is on the hunt to understand these objects, and we invite everyone to ring in the next year with the excitement of exploring the unknown.”
Getting the images to Earth is no easy task. As Stephanie Pappas at LiveScience reports, after snapping an image and storing it on its hard drive, New Horizons sends its data back on an antenna that transmits at only 12 watts, moving data at a snail's pace—only two kilobits per second. To send its recent images of the KBOs, Stern tells Pappas, it took the craft four hours just to transmit the data and another six hours for that information to reach Earth, where NASA’s Deep Space Network is able to gather the faint signal.
According to the press release, New Horizons is currently back in hibernation mode and will reawaken on June 4 to begin preparations for a January 1, 2019 rendezvous with 2014 MU69, which is nearly a billion miles beyond Pluto. Besides analyzing MU69, New Horizons will also make observations of a dozen other objects including dwarf planets and “Centaurs,” or objects with unstable orbits that float around in the Kuiper Belt.