Video Caption: NASA’s New Horizons spacecraft is speeding towards Pluto for the first-ever flyby on July 14, 2015. Scientists are eager to collect data on the dwarf planet’s chemical and atmospheric makeup, and the Ralph spectrometer will do just that. Instrument scientist Dennis Reuter discusses Ralph, Pluto, and exploration of our solar system’s last frontier, the Kuiper Belt.
LAUREL, Md. (NASA PR) — New Horizons’ newest images reveal Pluto’s largest moon Charon to be a world of chasms and craters. The most pronounced chasm, which lies in the southern hemisphere, is longer and miles deeper than Earth’s Grand Canyon, according to William McKinnon, deputy lead scientist with New Horizon’s Geology and Geophysics investigation team.
First dwarf planet discovered by an American, Lowell Observatory astronomer Clyde Tombaugh in 1930.
It is the final classical planet in the solar system to be visited by a spacecraft.
Pluto has five known moons — Charon, discovered in 1978; Nix and Hydra, discovered in 2005; Styx, discovered in 2011; and Kerberos, discovered in 2012.
Charon is so large (half of Pluto’s size, same diameter as Texas) that the Pluto-Charon system makes up a “double planet,” the only one in our solar system. Together Pluto and Charon orbit around their common center of gravity in the space between them.
Pluto is unusually difficult to study from Earth because it is so small and far away. It is 50,000 times fainter than Mars, with less than 1% of the red planet’s apparent diameter when viewed from Earth.
Pluto is the largest and brightest known member of the Kuiper Belt — the solar system’s third zone — the vast region of ancient, icy, rocky bodies stretching almost 2 billion miles beyond Neptune’s orbit.
The International Astronomical Union controversially opted in 2006 to classify Pluto and recently discovered large Kuiper Belt Objects as dwarf planets; debate continues on Pluto’s planetary classification.
LAUREL, Md. (NASA PR) — They’re a fascinating pair: Two icy worlds, spinning around their common center of gravity like a pair of figure skaters clasping hands. Scientists believe they were shaped by a cosmic collision billions of years ago, and yet, in many ways, they seem more like strangers than siblings.
A high-contrast array of bright and dark features covers Pluto’s surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon’s surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice.
“These two objects have been together for billions of years, in the same orbit, but they are totally different,” said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado.
Charon is about 750 miles (1200 kilometers) across, about half the diameter of Pluto—making it the solar system’s largest moon relative to its planet. Its smaller size and lower surface contrast have made it harder for New Horizons to capture its surface features from afar, but the latest, closer images of Charon’s surface show intriguing fine details.
Newly revealed are brighter areas on Charon that members of the mission’s Geology, Geophysics and Imaging team (GGI) suspect might be impact craters. If so, the scientists would put them to good use. “If we see impact craters on Charon, it will help us see what’s hidden beneath the surface,” said GGI leader Jeff Moore of NASA’s Ames Research Center. “Large craters can excavate material from several miles down and reveal the composition of the interior.”
In short, said GGI deputy team leader John Spencer of SwRI, “Charon is now emerging as its own world. Its personality is beginning to really reveal itself.”
What color is Pluto? The answer, revealed in the first maps made from New Horizons data, turns out to be shades of reddish brown. Although this is reminiscent of Mars, the cause is almost certainly very different. On Mars the coloring agent is iron oxide, commonly known as rust. On the dwarf planet Pluto, the reddish color is likely caused by hydrocarbon molecules that are formed when cosmic rays and solar ultraviolet light interact with methane in Pluto’s atmosphere and on its surface.
BALTIMORE, Md. (NASA PR) — New color images from NASA’s New Horizons spacecraft show two very different faces of the mysterious dwarf planet, one with a series of intriguing spots along the equator that are evenly spaced. Each of the spots is about 300 miles in diameter, with a surface area that’s roughly the size of the state of Missouri.
FLAGSTAFF, Ariz. (NASA PR) — Yes, there is methane on Pluto, and, no, it doesn’t come from cows. The infrared spectrometer on NASA’s Pluto-bound New Horizons spacecraft has detected frozen methane on Pluto’s surface; Earth-based astronomers first observed the chemical compound on Pluto in 1976.
WASHINGTON, DC (NASA PR) — If you lived on one of Pluto’s moons, you might have a hard time determining when, or from which direction, the sun will rise each day. Comprehensive analysis of data from NASA’s Hubble Space Telescope shows that two of Pluto’s moons, Nix and Hydra, wobble unpredictably.
“Hubble has provided a new view of Pluto and its moons revealing a cosmic dance with a chaotic rhythm,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate in Washington. “When the New Horizons spacecraft flies through the Pluto system in July we’ll get a chance to see what these moons look like up close and personal.”
WASHINGTON (NASA PR) — NASA’s New Horizons spacecraft is three months from returning to humanity the first-ever close up images and scientific observations of distant Pluto and its system of large and small moons.
“Scientific literature is filled with papers on the characteristics of Pluto and its moons from ground based and Earth orbiting space observations, but we’ve never studied Pluto up close and personal,” said John Grunsfeld, astronaut, and associate administrator of the NASA Science Mission Directorate at the agency’s Headquarters in Washington. “In an unprecedented flyby this July, our knowledge of what the Pluto systems is really like will expand exponentially and I have no doubt there will be exciting discoveries.”