Here’s a video showing the view of Pluto as the New Horizon probe flew past it:

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I missed this posting from New Horizons last week:

Scientists Study Nitrogen Provision for Pluto’s Atmosphere

The latest data from NASA’s New Horizons spacecraft reveal diverse features on Pluto’s surface and an atmosphere dominated by nitrogen gas. However, Pluto’s small mass allows hundreds of tons of atmospheric nitrogen to escape into space each hour.

So where does all this nitrogen come from? Kelsi Singer, a postdoctoral researcher at Southwest Research Institute, and her mentor Alan Stern, New Horizons principal investigator and SwRI associate vice president, outlined likely sources in a paper titled, “On the Provenance of Pluto’s Nitrogen.” The Astrophysical Journal Letters accepted the paper for publication on July 15, just a day after the spacecraft’s closest encounter with the icy dwarf planet.

“More nitrogen has to come from somewhere to resupply both the nitrogen ice that is moving around Pluto’s surface in seasonal cycles, and the nitrogen that is escaping off the top of the atmosphere as the result of heating by ultraviolet light from the Sun,” said Singer.

Singer and Stern looked at a number of different ways that nitrogen might be resupplied. They wondered if comets could deliver enough nitrogen to Pluto’s surface to resupply what is escaping its atmosphere. They also looked at whether craters made by the comets hitting the surface could excavate enough nitrogen – but that would require a very deep layer of nitrogen ice at the surface, which is not proven. The team also studied whether craters could expose more surface area, by punching through surface deposits that would likely be built up over time.

“We found that all of these effects, which are the major ones from cratering, do not seem to supply enough nitrogen to supply the escaping atmosphere over time,” continued Singer. “While it’s possible that the escape rate was not as high in the past as it is now, we think geologic activity is helping out by bringing nitrogen up from Pluto’s interior.”

And while the data weren’t in before this paper was written, the newest images of Pluto show land forms that suggest heat is rising beneath the surface, with troughs of dark matter either collecting, or bubbling up, between flat segments of crust, which could be related.

“Our pre-flyby prediction, made when we submitted the paper, is that it’s most likely that Pluto is actively resupplying nitrogen from its interior to its surface, possibly meaning the presence of ongoing geysers or cryovolcanism,” said Stern. “As data from New Horizons comes in, we will be very interested to see if this proves true.”

New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Ala. The Johns Hopkins University Applied Physics Laboratory in Laurel, Md., designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning.

Several new images from the New Horizons fly-by were released today during the press conference. Some of the images are shown below and many more are available in this New Horizons gallery.

New Horizons Team Finds Haze,
Flowing Ice on Pluto

Flowing ice and a surprising extended haze are among the newest discoveries from NASA’s New Horizons mission, which reveal distant Pluto to be an icy world of wonders.

Speeding away from Pluto just seven hours after its July 14 closest approach, the New Horizons spacecraft looked back and captured this spectacular image of Pluto’s atmosphere, backlit by the sun. The image reveals layers of haze that are several times higher than scientists predicted. Image Credit: NASA/JHUAPL/SWRI

“We knew that a mission to Pluto would bring some surprises, and now — 10 days after closest approach — we can say that our expectation has been more than surpassed,” said John Grunsfeld, NASA’s associate administrator for the Science Mission Directorate. “With flowing ices, exotic surface chemistry, mountain ranges, and vast haze, Pluto is showing a diversity of planetary geology that is truly thrilling.”

Just seven hours after closest approach, New Horizons aimed its Long Range Reconnaissance Imager (LORRI) back at Pluto, capturing sunlight streaming through the atmosphere and revealing hazes as high as 80 miles (130 kilometers) above Pluto’s surface. A preliminary analysis of the image shows two distinct layers of haze — one about 50 miles (80 kilometers) above the surface and the other at an altitude of about 30 miles (50 kilometers).

Four images from New Horizons’ Long Range Reconnaissance Imager (LORRI) were combined with color data from the Ralph instrument to create this global view of Pluto. (The lower right edge of Pluto in this view currently lacks high-resolution color coverage.) The images, taken when the spacecraft was 280,000 miles (450,000 kilometers) away, show features as small as 1.4 miles (2.2 kilometers), twice the resolution of the single-image view taken on July 13.

“My jaw was on the ground when I saw this first image of an alien atmosphere in the Kuiper Belt,” said Alan Stern, principal investigator for New Horizons at the Southwest Research Institute (SwRI) in Boulder, Colorado. “It reminds us that exploration brings us more than just incredible discoveries — it brings incredible beauty.”

Studying Pluto’s atmosphere provides clues as to what’s happening below.

“The hazes detected in this image are a key element in creating the complex hydrocarbon compounds that give Pluto’s surface its reddish hue,” said Michael Summers, New Horizons co-investigator at George Mason University in Fairfax, Virginia.

Models suggest the hazes form when ultraviolet sunlight breaks up methane gas particles — a simple hydrocarbon in Pluto’s atmosphere. The breakdown of methane triggers the buildup of more complex hydrocarbon gases, such as ethylene and acetylene, which also were discovered in Pluto’s atmosphere by New Horizons. As these hydrocarbons fall to the lower, colder parts of the atmosphere, they condense into ice particles that create the hazes. Ultraviolent sunlight chemically converts hazes into tholins, the dark hydrocarbons that color Pluto’s surface.

Scientists previously had calculated temperatures would be too warm for hazes to form at altitudes higher than 20 miles (30 kilometers) above Pluto’s surface.

“We’re going to need some new ideas to figure out what’s going on,” said Summers.

The New Horizons mission also found in LORRI images evidence of exotic ices flowing across Pluto’s surface and revealing signs of recent geologic activity, something scientists hoped to find but didn’t expect.

Annotated image of the northwestern region of Pluto’s Sputnik Planum, swirl-shaped patterns of light and dark suggest that a surface layer of exotic ices has flowed around obstacles and into depressions, much like glaciers on Earth.

The new images show fascinating details within the Texas-sized plain, informally named Sputnik Planum, which lies within the western half of Pluto’s heart-shaped feature, known as Tombaugh Regio. There, a sheet of ice clearly appears to have flowed — and may still be flowing — in a manner similar to glaciers on Earth.

“We’ve only seen surfaces like this on active worlds like Earth and Mars,” said mission co-investigator John Spencer of SwRI. “I’m really smiling.”

Additionally, new compositional data from New Horizons’ Ralph instrument indicate the center of Sputnik Planum is rich in nitrogen, carbon monoxide, and methane ices.

Pluto and Charon are shown in a composite of natural-color images from New Horizons. Images from the Long Range Reconnaissance Imager (LORRI) were combined with color data from the Ralph instrument to produce these views, which portray Pluto and Charon as an observer riding on the spacecraft would see them. The images were acquired on July 13 and 14, 2015

“At Pluto’s temperatures of minus-390 degrees Fahrenheit, these ices can flow like a glacier,” said Bill McKinnon, deputy leader of the New Horizons Geology, Geophysics and Imaging team at Washington University in St. Louis. “In the southernmost region of the heart, adjacent to the dark equatorial region, it appears that ancient, heavily-cratered terrain has been invaded by much newer icy deposits.”

View a simulated flyover using New Horizons’ close-approach images of Sputnik Planum and Pluto’s newly-discovered mountain range, informally named Hillary Montes, in the video here: go.nasa.gov/1MMEdTb

The New Horizons mission will continue to send data stored in its onboard recorders back to Earth through late 2016. The spacecraft currently is 7.6 million miles (12.2 million kilometers) beyond Pluto, healthy and flying deeper into the Kuiper Belt.

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA’s Science Mission Directorate. SwRI, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama.

For more information on the New Horizons mission, including fact sheets, schedules, video and images, visit: www.nasa.gov/newhorizons

The New Horizons team will hold a briefing today at 2:00 pm EDT: Complex World: New Horizons Pluto Science Update Set for July 24 – NASA.

The panel will include:

• Jim Green, director of Planetary Science at NASA Headquarters
• Alan Stern, New Horizons principal investigator at Southwest Research Institute (SwRI) in Boulder, Colorado
• Michael Summers, New Horizons co-investigator at George Mason University in Fairfax, Virginia
• William McKinnon, New Horizons co-investigator at Washington University in St. Louis
• Cathy Olkin, New Horizons deputy project scientist at SwRI

 

[ Update: Here is a video of the briefing:

]

More images from New Horizons of Pluto and its Moons were released today:

NASA’s New Horizons Finds Second Mountain Range in Pluto’s ‘Heart’

Click for larger image

A newly discovered mountain range lies near the southwestern margin of Pluto’s Tombaugh Regio (Tombaugh Region), situated between bright, icy plains and dark, heavily-cratered terrain. This image was acquired by New Horizons’ Long Range Reconnaissance Imager (LORRI) on July 14, 2015 from a distance of 48,000 miles (77,000 kilometers) and sent back to Earth on July 20. Features as small as a half-mile (1 kilometer) across are visible. Image Credit: NASA/JHUAPL/SWRI

Pluto’s icy mountains have company. NASA’s New Horizons mission has discovered a new, apparently less lofty mountain range on the lower-left edge of Pluto’s best known feature, the bright, heart-shaped region named Tombaugh Regio (Tombaugh Region).

These newly-discovered frozen peaks are estimated to be one-half mile to one mile (1-1.5 kilometers) high, about the same height as the United States’ Appalachian Mountains. The Norgay Montes (Norgay Mountains) discovered by New Horizons on July 15 more closely approximate the height of the taller Rocky Mountains.

The new range is just west of the region within Pluto’s heart called Sputnik Planum (Sputnik Plain). The peaks lie some 68 miles (110 kilometers) northwest of Norgay Montes.

This newest image further illustrates the remarkably well-defined topography along the western edge of Tombaugh Regio.

“There is a pronounced difference in texture between the younger, frozen plains to the east and the dark, heavily-cratered terrain to the west,” said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team (GGI) at NASA’s Ames Research Center in Moffett Field, California. “There’s a complex interaction going on between the bright and the dark materials that we’re still trying to understand.”

While Sputnik Planum is believed to be relatively young in geological terms – perhaps less than 100 million years old – the darker region probably dates back billions of years. Moore notes that the bright, sediment-like material appears to be filling in old craters (for example, the bright circular feature to the lower left of center).

This image was acquired by the Long Range Reconnaissance Imager (LORRI) on July 14 from a distance of 48,000 miles (77,000 kilometers) and sent back to Earth on July 20. Features as small as a half-mile (1 kilometer) across are visible. The names of features on Pluto have all been given on an informal basis by the New Horizons team.

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New Horizons ‘Captures’ Two of Pluto’s Smaller Moons

While Pluto’s largest moon, Charon, has grabbed most of the lunar spotlight, two of Pluto’s smaller and lesser-known satellites are starting to come into focus via new images from NASA’s New Horizons spacecraft.

Click for larger image

Nix and Hydra – the second and third moons to be discovered – are approximately the same size, but their similarity ends there.

New Horizons’ first color image of Nix, in which colors have been enhanced, reveals an intriguing region on the jelly bean-shaped satellite, which is estimated to be 26 miles (42 kilometers) long and 22 miles (36 kilometers) wide.

Although the overall surface color of Nix is neutral grey in the image, the newfound region has a distinct red tint. Hints of a bull’s-eye pattern lead scientists to speculate that the reddish region is a crater.

“Additional compositional data has already been taken of Nix, but is not yet downlinked. It will tell us why this region is redder than its surroundings,” said mission scientist Carly Howett, of the Southwest Research Institute, Boulder, Colorado. She added, “This observation is so tantalizing, I’m finding it hard to be patient for more Nix data to be downlinked.”

Meanwhile, the sharpest image yet received from New Horizons of Pluto’s satellite Hydra shows that its irregular shape resembles the state of Michigan. The new image was made by the Long Range Reconnaissance Imager (LORRI) on July 14, 2015 from a distance of 143,000 miles (231,000 kilometers), and shows features as small as 0.7 miles (1.2 kilometers) across. There appear to be at least two large craters, one of which is mostly in shadow. The upper portion looks darker than the rest of Hydra, suggesting a possible difference in surface composition. From this image, mission scientists have estimated that Hydra is 34 miles (55 kilometers) long and 25 miles (40 kilometers) wide.

“Before last week, Hydra was just a faint point of light, so it’s a surreal experience to see it become an actual place, as we see its shape and spot recognizable features on its surface for the first time,” said mission science collaborator Ted Stryk, of Roane State Community College in Tennessee.

Images of Pluto’s most recently discovered moons, Styx and Kerberos, are expected to be transmitted to Earth no later than mid-October.

Nix and Hydra were both discovered in 2005 using Hubble Space Telescope data by a research team led by New Horizons project scientist Hal Weaver, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland. New Horizons’ findings on the surface characteristics and other properties of Nix and Hydra will help scientists understand the origins and subsequent history of Pluto and its moons.