New Horizons Crosses the Orbit of Neptune
 
August 25, 2014:  NASA's Pluto-bound New Horizons spacecraft has traversed
the orbit of Neptune. This is its last major crossing en route to becoming
the first probe to make a close encounter with distant Pluto on July 14,
2015.
 
The sophisticated piano-sized spacecraft, which launched in January 2006,
reached Neptune's orbit -- nearly 2.75 billion miles from Earth -- in a
record eight years and eight months. New Horizons' milestone matches
precisely the 25th anniversary of the historic encounter of NASA's Voyager
2 spacecraft with Neptune on Aug. 25, 1989.
 
http://tinyurl.com/koatvz6
 
NASA's Pluto-bound New Horizons spacecraft captured this view of the giant
planet Neptune and its large moon Triton on July 10, 2014, from a distance
of about 2.45 billion miles (3.96 billion kilometers) - more than 26 times
the distance between the Earth and sun. The 967-millisecond exposure was
taken with the New Horizons telescopic Long-Range Reconnaissance Imager
(LORRI). Image credit: NASA/Johns Hopkins University Applied Physics
Laboratory/Southwest Research Institute. More
 
"It's a cosmic coincidence that connects one of NASA's iconic past
outer solar system explorers, with our next outer solar system
explorer," said Jim Green, director of NASA's Planetary Science
Division, NASA Headquarters in Washington. "Exactly 25 years ago at
Neptune, Voyager 2 delivered our `first' look at an unexplored planet. Now
it will be New Horizons' turn to reveal the unexplored Pluto and its moons
in stunning detail next summer on its way into the vast outer reaches of
the solar system."
 
New Horizons now is about 2.48 billion miles from Neptune -- nearly 27
times the distance between the Earth and our sun -- as it crosses the giant
planet's orbit at 10:04 p.m. EDT Monday. Although the spacecraft will be
much farther from the planet than Voyager 2's closest approach, New
Horizons' telescopic camera was able to obtain several long-distance
"approach" shots of Neptune on July 10.
 
"NASA's Voyager 1 and 2 explored the entire middle zone of the solar
system where the giant planets orbit," said Alan Stern, New Horizons
principal investigator at the Southwest Research Institute in Boulder,
Colorado. "Now we stand on Voyager's broad shoulders to explore the
even more distant and mysterious Pluto system."
 
Several senior members of the New Horizons science team were young members
of Voyager's science team in 1989. Many remember how Voyager 2's approach
images of Neptune and its planet-sized moon Triton fueled anticipation of
the discoveries to come. They share a similar, growing excitement as New
Horizons begins its approach to Pluto.
 
http://tinyurl.com/exshu
 
Click to visit the New Horizons home page"The feeling 25 years ago was
that this was really cool, because we're going to see Neptune and Triton
up-close for the first time," said Ralph McNutt of the Johns Hopkins
University Applied Physics Laboratory (APL) in Laurel, Maryland, who leads
the New Horizons energetic-particle investigation and served on the Voyager
plasma-analysis team. "The same is happening for New Horizons. Even
this summer, when we're still a year out and our cameras can only spot
Pluto and its largest moon as dots, we know we're in for something
incredible ahead."
 
Voyager's visit to the Neptune system revealed previously unseen features
of Neptune itself, such as the Great Dark Spot, a massive storm similar to,
but not as long-lived, as Jupiter's Great Red Spot. Voyager also, for the
first time, captured clear images of the ice giant's ring system, too faint
to be clearly viewed from Earth. "There were surprises at Neptune and
there were surprises at Triton," said Ed Stone, Voyager's
long-standing project scientist from the California Institute of Technology
in Pasadena. "I'm sure that will continue at Pluto."
 
Many researchers feel the 1989 Neptune flyby -- Voyager's final planetary
encounter -- might have offered a preview of what's to come next summer.
Scientists suggest that Triton, with its icy surface, bright poles, varied
terrain and cryovolcanoes, is a Pluto-like object that Neptune pulled into
orbit. Scientists recently restored Voyager's footage of Triton and used it
to construct the best global color map of that strange moon yet -- further
whetting appetites for a Pluto close-up.
 
"There is a lot of speculation over whether Pluto will look like
Triton, and how well they'll match up," McNutt said. "That's the
great thing about first-time encounters like this -- we don't know exactly
what we'll see, but we know from decades of experience in first-time
exploration of new planets that we will be very surprised."
 
Similar to Voyager 1 and 2's historic observations, New Horizons also is on
a path toward potential discoveries in the Kuiper Belt, which is a
disc-shaped region of icy objects past the orbit of Neptune, and other
unexplored realms of the outer solar system and beyond.
 
"No country except the United States has the demonstrated capability
to explore so far away," said Stern. "The U.S. has led the
exploration of the planets and space to a degree no other nation has, and
continues to do so with New Horizons. We're incredibly proud that New
Horizons represents the nation again as NASA breaks records with its
newest, farthest and very capable planetary exploration spacecraft."
 
Credits:
Production editor: Dr. Tony Phillips | Credit: Science{at}NASA
 
More information:
 
Voyager 1 and 2 were launched 16 days apart in 1977, and one of the
spacecraft visited Jupiter, Saturn, Uranus and Neptune. Voyager 1 now is
the most distant human-made object, about 12 billion miles (19 billion
kilometers) away from the sun. In 2012, it became the first human-made
object to venture into interstellar space. Voyager 2, the longest
continuously operated spacecraft, is about 9 billion miles (15 billion
kilometers) away from our sun.
 
New Horizons is the first mission in NASA's New Frontiers program. APL
manages the mission for NASA's Science Mission Directorate at NASA
Headquarters. APL also built and operates the New Horizons spacecraft.
 
The Voyager spacecraft were built and continue to be operated by NASA's Jet
Propulsion Laboratory in Pasadena, California. The Voyager missions are
part of NASA's Heliophysics System Observatory, sponsored by the
Heliophysics Division of the Science Mission Directorate.
 
To view the Neptune images taken by New Horizons and learn more about the
mission, visit:
 
http://www.nasa.gov/newhorizons
 
For more information about the Voyager spacecraft, visit:
 
http://www.nasa.gov/voyager
 
 
Regards,
 
Roger

--- D'Bridge 3.99