[meteorite-list] New Horizons Color Images Reveal Two Distinct Faces of Pluto, Series of Spots that Fascinate

[Ron Baalke]

http://www.nasa.gov/feature/new-horizons-color-images-reveal-two-distinct-faces-of-pluto-series-of-spots-that-fascinate

New Horizons Color Images Reveal Two Distinct Faces of Pluto, Series of 
Spots that Fascinate
July 1, 2015

New color images from NASA's New Horizons spacecraft show two very different 
faces of the mysterious dwarf planet, one with a series of intriguing 
spots along the equator that are evenly spaced. Each of the spots is about 
300 miles in diameter, with a surface area that's roughly the size of 
the state of Missouri.

Scientists have yet to see anything quite like the dark spots; their presence 
has piqued the interest of the New Horizons science team, due to the remarkable 
consistency in their spacing and size. While the origin of the spots is 
a mystery for now, the answer may be revealed as the spacecraft continues 
its approach to the mysterious dwarf planet. "It's a real puzzle - we don't 
know what the spots are, and we can't wait to find out," said New Horizons 
principal investigator Alan Stern of the Southwest Research Institute, 
Boulder. "Also puzzling is the longstanding and dramatic difference in 
the colors and appearance of Pluto compared to its darker and grayer moon 
Charon."

New Horizons team members combined black-and-white images of Pluto and 
Charon from the spacecraft's Long-Range Reconnaissance Imager (LORRI) 
with lower-resolution color data from the Ralph instrument to produce 
these views. We see the planet and its largest moon in approximately true 
color, that is, the way they would appear if you were riding on the New 
Horizons spacecraft. About half of Pluto is imaged, which means features 
shown near the bottom of the dwarf planet are at approximately at the 
equatorial line.

New color images from NASA's New Horizons spacecraft show two very different 
faces of the mysterious dwarf planet, one with a series of intriguing 
spots along the equator that are evenly spaced.

More New Horizons News for Wednesday, July 1:

Instruments Prepare to Search for Clouds in Pluto’s Atmosphere

If Pluto has clouds, New Horizons can detect them. Both the high-resolution 
LORRI imager and the Ralph color imager will be used to look for clouds 
across the face of Pluto during its approach and departure from the planet. 
"We're looking for clouds in our images using a number of techniques," 
said science team postdoc Kelsi Singer of the Southwest Research Institute, 
"If we find clouds, their presence will allow us to track the speeds and 
directions of Pluto's winds."

New Horizons Team Says "Bravo!" To Earth-Based Pluto Observers

For more than two decades, planetary scientists have raced to get a spacecraft 
to Pluto against predictions that its atmosphere would disappear - literally 
freezing onto the surface - efore it could be explored. This week, planetary 
scientists using ground-based telescopes and NASA's SOFIA airborne observatory 
confirmed that "Pluto's atmosphere is alive and well, and has not frozen 
out on the surface," according to New Horizons deputy project scientist 
Leslie Young, Southwest Research Institute, Boulder. Added Young, "We're 
delighted!"

"The SOFIA observations will also be essential for linking ground-based 
studies to the results from the New Horizons Pluto encounter for decades 
to come", said Cathy Olkin, Southwest Research Institute, Boulder, co-investigator 
on NASA's New Horizons mission.


PEPSSI Instrument Tastes Pluto's Atmosphere

The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) 
instrument aboard New Horizons is sending back data daily, sampling the 
space environment near Pluto. PEPSSI is designed to detect ions (atoms 
that have lost or gained one or more electrons) that have escaped from 
Pluto's atmosphere. As they depart, these atoms become caught up in the 
solar wind, the stream of subatomic particles that emanates from the Sun. 
PEPSSI's job is to tell scientists about the composition of Pluto's escaping 
atmosphere and how quickly the atmosphere is escaping.

The location of New Horizons' Pluto Energetic Particle Spectrometer Science 
Investigation (PEPSSI) instrument is shown.

New Horizons is now less than 9.5 million miles (15 million kilometers) 
from the Pluto system. The spacecraft is healthy and all systems are operating 
normally.

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. The Southwest Research 
Institute, 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.

To view images from New Horizons and learn more about the mission visit: 

http://www.nasa.gov/newhorizons and http://pluto.jhuapl.edu

Follow the New Horizons mission on social media, and use the hashtag #PlutoFlyby 
to join the conversation. The mission's official NASA Twitter account 
is @NASANewHorizons. Live updates are available on Facebook at: 
https://www.facebook.com/new.horizons1

Last Updated: July 1, 2015
Editor: Lillian Gipson