LAUREL, Md. — Nola Taylor Redd reports: With less than 24 hours to go before NASA’s New Horizons probe makes its close flyby of Pluto, scientists are already learning more about the dwarf planet than ever before, including the fact that it is bigger than previously thought.
New Horizons’ latest views of Pluto have shown the dwarf planet to be 1,473 miles (2,370 kilometers) across, making it the largest body in the icy Kuiper Belt at the edge of the solar system. The observations also confirmed the presence of a polar ice cap on Pluto, and measured three of the dwarf planet’s moons.
“Pluto is not disappointing,” said principal investigator Alan Stern, of the Southwest Research Institute in Boulder, Colorado, during a NASA briefing here today (July 13).
As New Horizons closes in, the spacecraft made the most precise measurements to date of Pluto’s size using methods similar to those employed by NASA’s Voyager spacecraft. The new diameter of the dwarf planet makes it larger than fellow Kuiper Belt denizen Eris, which is 1,445 miles (2,326 km) in diameter.
Previous estimates for the size of Pluto had put its radius at 1,430 miles (2,301 km). But Pluto now stands as the undisputed king of the Kuiper Belt.
“This settles the debate about the largest object in the Kuiper Belt,” Stern said. Read the rest of this entry »
After a Voyage of More than 3 Billion Miles, NASA’s New Horizons Spacecraft is Ready to Begin Exploring PlutoPosted: January 23, 2015
NASA’s New Horizons spacecraft recently began its long-awaited, historic encounter with Pluto. The spacecraft is entering the first of several approach phases that culminate July 14 with the first close-up flyby of the dwarf planet, 4.67 billion miles (7.5 billion kilometers) from Earth.
“We’ve completed the longest journey any spacecraft has flown from Earth to reach its primary target, and we are ready to begin exploring.”
— Alan Stern, New Horizons principal investigator from Southwest Research Institute in Boulder, Colorado
“NASA first mission to distant Pluto will also be humankind’s first close up view of this cold, unexplored world in our solar system,” said Jim Green, director of NASA’s Planetary Science Division at the agency’s Headquarters in Washington. “The New Horizons team worked very hard to prepare for this first phase, and they did it flawlessly.”
The fastest spacecraft when it was launched, New Horizons lifted off in January 2006. It awoke from its final hibernation period last month after a voyage of more than 3 billion miles, and will soon pass close to Pluto, inside the orbits of its five known moons.
“NASA first mission to distant Pluto will also be humankind’s first close up view of this cold, unexplored world in our solar system. The New Horizons team worked very hard to prepare for this first phase, and they did it flawlessly.”
— Jim Green, director of NASA’s Planetary Science Division
In preparation for the close encounter, the mission’s science, engineering and spacecraft operations teams configured the piano-sized probe for distant observations of the Pluto system that start Sunday, Jan. 25 with a long-range photo shoot.
The images captured by New Horizons’ telescopic 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 135 million miles (220 million kilometers) 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 Alan Stern, New Horizons principal investigator from Southwest Research Institute in Boulder, Colorado. Read the rest of this entry »