An international team of scientists, including researchers from NASA’s Ames Research Center in California’s Silicon Valley, analyzed New Horizons data from Pluto’s atmosphere and surface, using numerical simulations of Pluto’s climate to reveal that these ice caps are formed in a way that differs completely from on Earth.
Images from NASA’s New Horizons spacecraft depict bright and dark patches on Pluto’s surface for the first time, exposing the principal objective of the New Horizons close flyby in mid-July.
New Horizons’ telescopic Long-Range Reconnaissance Imager (LORRI) took the photos camera from a distance of 70 million miles (113 million kilometers) in early to mid-April.
The raw, unedited photos sent back to Earth are sharpened using a method known as image deconvolution. The data revealed that the dwarf planet has extensive surface marks, some bright and some dark, including a brilliant region near one pole that may be a polar cap, according to New Horizons scientists.
“As we approach the Pluto system we are starting to see intriguing features such as a bright region near Pluto’s visible pole, starting the great scientific adventure to understand this enigmatic celestial object,” says John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “As we get closer, the excitement is building in our quest to unravel the mysteries of Pluto using data from New Horizons.”
After traveling more than nine years through space, it’s stunning to see Pluto, literally a dot of light as seen from Earth, becoming a real place right before our eyes. These incredible images are the first in which we can begin to see detail on Pluto, and they are already showing us that Pluto has a complex surface.
Alan Stern
Pluto’s largest moon, Charon, is also visible in the photographs, revolving in its 6.4-day orbit. The camera’s exposure periods, which were set to a tenth of a second, were too short to identify Pluto’s four considerably smaller and fainter moons.
The cooling caused by the expansion of the air in upward motions causes atmospheric temperatures to drop with height on our planet. The chilly atmosphere cooled temperatures at the surface.
When a moist breeze reaches a mountain on Earth, its water vapor cools and condenses, generating clouds and, eventually, the snow observed on the summits. On Pluto, however, the opposite is true. Because the methane gas, which is more concentrated higher up, absorbs solar radiation, the dwarf planet’s atmosphere gets warmer as altitude increases.
The atmosphere is too thin to have an effect on surface temperatures, which remain constant. Unlike on Earth, where upward winds dominate, downhill winds dominate on Pluto.
Pluto has been a mystery since its discovery in 1930. It orbits our sun at a distance of more than 3 billion miles (nearly 5 billion kilometers), and scientists have struggled to learn anything about its surface.
The mission science team can now see clear differences in brightness throughout Pluto’s surface as it rotates according to the latest New Horizons photographs.
“After traveling more than nine years through space, it’s stunning to see Pluto, literally a dot of light as seen from Earth, becoming a real place right before our eyes,” said Alan Stern, New Horizons principal investigator at Southwest Research Institute in Boulder, Colorado. “These incredible images are the first in which we can begin to see detail on Pluto, and they are already showing us that Pluto has a complex surface.”
As New Horizons approaches its July encounter with Pluto, the photographs it returns will improve substantially.
“We can only imagine what surprises will be revealed when New Horizons passes approximately 7,800 miles (12,500 kilometers) above Pluto’s surface this summer,” said Hal Weaver, the mission’s project scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland.