Pluto’s Wright Mons in Color
Scientists with NASA’s New Horizons mission have assembled this highest-resolution color view of one of two potential cryovolcanoes spotted on the surface of Pluto by the New Horizons spacecraft in July 2015.
At about 90 miles (150 kilometers) across and 2.5 miles (4 kilometers) high, this feature – informally named Wright Mons – is enormous. If it is in fact an ice volcano, as suspected, it would be the largest such feature discovered in the outer solar system.
Mission scientists are intrigued by the sparse distribution of red material in the image and wonder why it is not more widespread. Also perplexing is that there is only one identified impact crater on Wright Mons itself, telling scientists that the surface (as well as some of the crust underneath) was created relatively recently. This is turn may indicate that Wright Mons was volcanically active late in Pluto’s history.
This composite image includes pictures taken by the New Horizons spacecraft’s Long Range Reconnaissance Imager (LORRI) on July 14, 2015, from a range of about 30,000 miles (48,000 kilometers), showing features as small as 1,500 feet (450 meters) across. Sprinkled across the LORRI mosaic is enhanced color data from the Ralph/Multispectral Visible Imaging Camera (MVIC) gathered about 20 minutes after the LORRI snapshots were taken, from a range of 21,000 miles (34,000 kilometers) and at a resolution of about 2,100 feet (650 meters) per pixel. The entire scene is 140 miles (230 kilometers) across.
Last Updated: Jan. 14, 2016
Editor: Steve Fox
‘X’ Marks a Curious Corner on Pluto’s Icy Plains
Transmitted to Earth on Dec. 24, 2015, this image from the Long Range Reconnaissance Imager (LORRI) extends New Horizons’ highest-resolution swath of Pluto to the center of Sputnik Planum, the informally named plain that forms the left side of Pluto’s “heart.” Mission scientists believe the pattern of the cells stems from the slow thermal convection of the nitrogen-dominated ices. The darker patch at the center of the image is likely a dirty block of water ice “floating” in denser solid nitrogen, and which has been dragged to the edge of a convection cell. Also visible are thousands of pits in the surface, which scientists believe may form by sublimation. Image is about 45 miles (72 kilometers) wide.
Credits: NASA/JHUAPL/SwRI
“X” marks the spot of some intriguing surface activity in the latest picture of Pluto returned from NASA’s New Horizons spacecraft.
Transmitted to Earth on Dec. 24, this image from the Long Range Reconnaissance Imager (LORRI) extends New Horizons’ highest-resolution views of Pluto to the very center of Sputnik Planum, the informally named icy plain that forms the left side of Pluto’s “heart” feature.
“This part of Pluto is acting like a lava lamp, if you can imagine a lava lamp as wide as, and even deeper than, Hudson Bay.”
- William McKinnon, deputy lead of the New Horizons Geology Team
Sputnik Planum is at a lower elevation than most of the surrounding area by a couple of miles, but is not completely flat. Its surface is separated into cells or polygons 10 to 25 miles (16 to 40 kilometers) wide, and when viewed at low sun angles (with visible shadows), the cells are seen to have slightly raised centers and ridged margins, with about 100 yards (100 meters) of overall height variation.
Mission scientists believe the pattern of the cells stems from the slow thermal convection of the nitrogen-dominated ices that fill Sputnik Planum. A reservoir that’s likely several miles or kilometers deep in some places, the solid nitrogen is warmed at depth by Pluto’s modest internal heat, becomes buoyant and rises up in great blobs, and then cools off and sinks again to renew the cycle.
“This part of Pluto is acting like a lava lamp,” said William McKinnon, deputy lead of the New Horizons Geology, Geophysics and Imaging team, from Washington University in St. Louis, “if you can imagine a lava lamp as wide as, and even deeper than, Hudson Bay.”
Computer models by the New Horizons team show that these blobs of overturning solid nitrogen can slowly evolve and merge over millions of years. The ridged margins, which mark where cooled nitrogen ice sinks back down, can be pinched off and abandoned. The “X” feature is likely one of these—a former quadruple junction where four convection cells meet. Numerous, active triple junctions can be seen elsewhere in the LORRI mosaic.
NOTE: for best viewing, click on the mosaic and zoom in.
Last Updated: Jan. 11, 2016
Editor: Bill Keeter
el dispensador dice:
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mejor ocúpate en dejar tu propia huella.
ENERO 14, 2016.-
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