NASA’s New Horizons is entering the first of several approach phases that culminate July 14 with the first close-up flyby of Pluto.
This is an artist’s concept of NASA’s New Horizons during its planned encounter with Pluto and its moon, Charon: the craft’s miniature cameras, radio science experiment, ultraviolet and infrared spectrometers and space plasma experiments would characterize the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto’s atmosphere in detail; the spacecraft’s most prominent design feature is a nearly 2.1-m dish antenna, through which it would communicate with Earth from as far as 7.5 billion km away. Image credit: Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute / JHUAPL / SwRI.
The fastest spacecraft when it was launched, New Horizons lifted off in January 2006.
It awoke from its final hibernation period last month and will soon pass close to Pluto, inside the orbits of its five known moons.
In preparation for the close encounter, NASA scientists configured the space probe for distant observations of the Pluto system that start January 25, 2015, with a long-range photo shoot.
The images captured by the probe’s Long-Range Reconnaissance Imager (LORRI) will give mission scientists a continually improving look at the dynamics of Pluto’s moons.
The images also will play a critical role in navigating the spacecraft as it covers the remaining 220 million km to Pluto.
“We’ve completed the longest journey any spacecraft has flown from Earth to reach its primary target, and we are ready to begin exploring,” said Dr Alan Stern of Southwest Research Institute in Boulder, Colorado.
LORRI will take hundreds of pictures of Pluto over the next few months to refine current estimates of the distance between the spacecraft and the dwarf planet.
Though the Pluto system will resemble little more than bright dots in the camera’s view until May, mission navigators will use the data to design course-correction maneuvers to aim the spacecraft toward its target point this summer. The first such maneuver could occur as early as March.
Spacecraft operators also track New Horizons using radio signals from NASA’s Deep Space Network.
The optical navigation campaign that begins January 2015 marks the first time pictures from New Horizons will be used to help pinpoint Pluto’s location.
Throughout the first approach phase, which runs until spring, New Horizons will conduct a significant amount of additional science.
Spacecraft instruments will gather continuous data on the interplanetary environment where the planetary system orbits, including measurements of the high-energy particles streaming from the sun and dust-particle concentrations in the inner reaches of the Kuiper Belt.
In addition to Pluto, this area, the unexplored outer region of the solar system, potentially includes thousands of similar icy, rocky small planets.
More intensive studies of Pluto begin in the spring, when the cameras and spectrometers aboard the probe will be able to provide image resolutions higher than the most powerful telescopes on Earth.
Eventually, New Horizons will obtain images good enough to map Pluto and its moons more accurately than achieved by previous missions.
