Article written by Matt Williams
Published on Universe Today
February 21, 2017
In 2006, during their 26th General Assembly, the International Astronomical Union (IAU) adopted a formal definition of the term “planet”. This was done in the hopes of dispelling ambiguity over which bodies should be designated as “planets”, an issue that had plagued astronomers ever since they discovered objects beyond the orbit of Neptune that were comparable in size to Pluto.
Needless to say, the definition they adopted resulted in fair degree of controversy from the astronomical community. For this reason, a team of planetary scientists – which includes famed “Pluto defender” Alan Stern – have come together to propose a new meaning for the term “planet”. Based on their geophysical definition, the term would apply to over 100 bodies in the Solar System, including the Moon itself.
Read the complete article at the Universe Today website: SAD ABOUT PLUTO? HOW ABOUT 110 PLANETS IN THE SOLAR SYSTEM INSTEAD?
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By Matt Williams
Matt Williams is the Curator of the Guide to Space for Universe Today, a regular contributor to HeroX, a science fiction author, and a Taekwon-Do instructor. He lives with his family on Vancouver Island in beautiful BC.
This work is licensed under a Creative Commons Attribution 4.0 International License
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.“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).
“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.
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.
“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: http://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: http://www.nasa.gov/newhorizons
|July 17, 2015
In the latest data from NASA’s New Horizons spacecraft, a new close-up image of Pluto reveals a vast, craterless plain that appears to be no more than 100 million years old, and is possibly still being shaped by geologic processes. This frozen region is north of Pluto’s icy mountains, in the center-left of the heart feature, informally named “Tombaugh Regio” (Tombaugh Region) after Clyde Tombaugh, who discovered Pluto in 1930.
“This terrain is not easy to explain,” said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team (GGI) at NASA’s Ames Research Center in Moffett Field, California. “The discovery of vast, craterless, very young plains on Pluto exceeds all pre-flyby expectations.”
This fascinating icy plains region — resembling frozen mud cracks on Earth — has been informally named “Sputnik Planum” (Sputnik Plain) after the Earth’s first artificial satellite. It has a broken surface of irregularly-shaped segments, roughly 12 miles (20 kilometers) across, bordered by what appear to be shallow troughs. Some of these troughs have darker material within them, while others are traced by clumps of hills that appear to rise above the surrounding terrain. Elsewhere, the surface appears to be etched by fields of small pits that may have formed by a process called sublimation, in which ice turns directly from solid to gas, just as dry ice does on Earth.
Scientists have two working theories as to how these segments were formed. The irregular shapes may be the result of the contraction of surface materials, similar to what happens when mud dries. Alternatively, they may be a product of convection, similar to wax rising in a lava lamp. On Pluto, convection would occur within a surface layer of frozen carbon monoxide, methane and nitrogen, driven by the scant warmth of Pluto’s interior.
Pluto’s icy plains also display dark streaks that are a few miles long. These streaks appear to be aligned in the same direction and may have been produced by winds blowing across the frozen surface.
The Tuesday “heart of the heart” image was taken when New Horizons was 48,000 miles (77,000 kilometers) from Pluto, and shows features as small as one-half mile (1 kilometer) across. Mission scientists will learn more about these mysterious terrains from higher-resolution and stereo images that New Horizons will pull from its digital recorders and send back to Earth during the next year.
The New Horizons Atmospheres team observed Pluto’s atmosphere as far as 1,000 miles (1,600 kilometers) above the surface, demonstrating that Pluto’s nitrogen-rich atmosphere is quite extended. This is the first observation of Pluto’s atmosphere at altitudes higher than 170 miles above the surface (270 kilometers).
The New Horizons Particles and Plasma team has discovered a region of cold, dense ionized gas tens of thousands of miles beyond Pluto — the planet’s atmosphere being stripped away by the solar wind and lost to space.
“This is just a first tantalizing look at Pluto’s plasma environment,” said New Horizons co-investigator Fran Bagenal, University of Colorado, Boulder.
“With the flyby in the rearview mirror, a decade-long journey to Pluto is over –but, the science payoff is only beginning,” said Jim Green, director of Planetary Science at NASA Headquarters in Washington. “Data from New Horizons will continue to fuel discovery for years to come.”
Alan Stern, New Horizons principal investigator from the Southwest Research Institute (SwRI), Boulder, Colorado, added, “We’ve only scratched the surface of our Pluto exploration, but it already seems clear to me that in the initial reconnaissance of the solar system, the best was saved for last.”
New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. 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 leads the mission, science team, payload operations and encounter science planning.
For more information on the New Horizons mission, including fact sheets, schedules, video and new images, visit http://www.nasa.gov/newhorizons and http://solarsystem.nasa.gov/planets/plutotoolkit.cfm
July 16, 2015
MEDIA ADVISORY M15-109
NASA will hold a media briefing at 1 p.m. EDT Friday, July 17, to reveal new images of Pluto and discuss new science findings from Tuesday’s historic flyby.
The briefing will be held in James E. Webb Auditorium at NASA Headquarters, located at 300 E St. SW in Washington. NASA Television and the agency’s website will carry the briefing live.
Participants in the briefing will be:
- Jim Green, director of Planetary Science at NASA Headquarters in Washington
- Alan Stern, New Horizons principal investigator at Southwest Research Institute (SwRI) in Boulder, Colorado
- Randy Gladstone, New Horizons co-investigator at SwRI in San Antonio
- Jeffrey Moore, New Horizons co-investigator at NASA’s Ames Research Center in Moffett Field, California
- Fran Bagenal, New Horizons co-investigator, University of Colorado, Boulder
Media may participate by phone. To join the briefing by phone, reporters must email their name, affiliation and telephone number to Karen Northon at karen.northon by noon Friday.
Media and the public also may ask questions during the briefing on Twitter using the hashtag #askNASA.
For NASA TV streaming video, scheduling and downlink information, visit:
For more information on the New Horizons mission, including fact sheets, schedules, video and images, visit: