The moment that we have been waiting for is almost upon us. For over a decade, scientists and space enthusiasts have been watching the skies, waiting for New Horizons to reach Pluto and provided us with our first real look at this icy world. At long last, the moment is nearly here. Although the spacecraft isn't set to reach Pluto until July 2015, it's already bringing us new insights into this distant region of our solar system.
Case in point, NASA just announced that, for the first time, New Horizons has been able to capture some of the dwarf planet's smaller moons, Hydra and Nix. It may be surprising to some to hear that Pluto has more than one moon. After all, the Earth just has just one natural satellite. But in truth, Pluto has a an entire family. Currently, it has a total of five known moons: Charon, Hydra, Nix, Styx, and Kerberos.
The images that have been released consist of seven frames, which were taken by New Horizons from Jan. 27 to Feb. 8, 2015. Each frame in the animation is a combination of five 10-second images. At the time that the images were captures, the craft was still some 115 million miles (186 million km) from Pluto.
That may sound rather distant; however, for comparison, at present time, New Horizons is a staggering 2.98 billion miles (4.8 billion km) from Earth. For a bit more perspective, on average, our own moon is just a few hundred thousand miles from Earth. To be exact, the moon is 238,800 miles (384,400 km) distant.
So although New Horizons is a lot closer to Pluto, that "closeness" is entirely relative. It it sill millions of miles away. But fear not, New Horizons is still some distance from its final target, so don't be too dismayed by the graininess of the above footage. The images will improve as the craft approaches its anticipated arrival date.
In the images, Hydra is noted by a yellow box and Nix is in the orange. If the image is too blurry, you can see a version of the animation with some of the background stars and noise cleared out below.
These photos have been released to honor the 85th anniversary of the first spotting of Pluto by Clyde Tombaugh, which occurred at the Lowell Observatory in Flagstaff, AZ. New Horizons science team member John Spencer from the Southwest Research Institute (SwRI), said of this release, “It’s thrilling to watch the details of the Pluto system emerge as we close the distance to the spacecraft’s July 14 encounter. This first good view of Nix and Hydra marks another major milestone, and a perfect way to celebrate the anniversary of Pluto’s discovery.”
As an interesting aside, Pluto is a long ways from the sun. As a result, it has a very large orbit, and because its orbit is so large, it takes the tiny dwarf planet some 247 years to complete one revolution around the Sun. Ultimately, this is equal to 90,553 Earth days. As such, between the time it was discovered and the time that it was reclassified as a dwarf planet, Pluto didn’t even complete one orbit around the sun. And it still has more than 160 years to go. In fact, we won’t observe a complete orbit until 2178.