Author Topic: NASA - Voyager 1 and 2 updates  (Read 75895 times)

Offline kevin-rf

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Re: NASA - Voyager 1 and 2 updates
« Reply #40 on: 04/24/2011 12:23 AM »
I still remember being in grade school during the jupiter encounter and feeling like the up and coming saturn would be a life time away!
If you're happy and you know it,
It's your med's!

Offline joek

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Re: NASA - Voyager 1 and 2 updates
« Reply #41 on: 04/24/2011 01:01 AM »
I remember being there doing image processing during Jupiter encounter and wondering if it would survive.  That was a heart-stopping life time.  :)

Offline joek

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Re: NASA - Voyager 1 and 2 updates
« Reply #42 on: 04/24/2011 04:43 AM »
p.s. And I'll take this opportunity to pontificate that robotic exploration can be just as exciting and fulfilling as HSF.  HSF may be more exciting to many, but for those who have experienced it, living vicariously through robotic probes can be just as fulfilling and exciting.

The deep dark unknowns are where we lived.  What was beyond Mars?  Was the asteroid belt a danger?  Could we make it to Jupiter and beyond?

The precursor Pioneer 10/11 made it past the belt, but both had problems at Jupiter encounter.  IIRC... We almost lost Pioneer 10 due to anomalous/corrupted command sequence, and Pioneer 11 never fully recovered one of it's imaging tubes (I think think blue).  They got hurt, and hurt bad.  We all felt the hurt, and it was palpable.

Jupiter rad environment is a b**ch and no one (including Van Allen) was really prepared for what we found.  One of the great understatements was a post-encounter presentation titled "It's Really Hot In There"  We went where no man had gone, or could go.  Yet we survived.  More precisely, the mechanical progeny of our blood, sweat, tears and hopes survived.

Voyager was much bigger, sophisticated (and expensive) than Pioneer--and there was a lot more that could go wrong.  Even with Pioneer paving the way, Voyager Jupiter encounter was still a white-knuckle hold-your-breath moment.  Run the gauntlet!  Go baby go!  Talk to us!  IMHO no launch compares.

That the Pioneer's lived for another 25-30 years, and the Voyagers still live after 30+ years to tell their tale is truly amazing.  Kudo's to everyone involved then and now.  I am proud to say I contributed in very small part to the Pioneer and Voyager missions--and am as proud as if I had contributed to any Apollo missions.

Online Robotbeat

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Re: NASA - Voyager 1 and 2 updates
« Reply #43 on: 04/25/2011 03:30 PM »
Thank you, joek. :)
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Offline jacqmans

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Re: NASA - Voyager 1 and 2 updates
« Reply #44 on: 04/29/2011 03:27 AM »
News release: 2011-128                                                                     April 28, 2011

Voyager Set to Enter Interstellar Space

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2011-128&cid=release_2011-128

More than 30 years after they left Earth, NASA's twin Voyager probes are now at the edge of the solar system. Not only that, they're still working. And with each passing day they are beaming back a message that, to scientists, is both unsettling and thrilling.

The message is, "Expect the unexpected."

"It's uncanny," says Ed Stone of the California Institute of Technology in Pasadena, Voyager Project Scientist since 1972. "Voyager 1 and 2 have a knack for making discoveries."

Today, April 28, 2011, NASA held a live briefing to reflect on what the Voyager mission has accomplished--and to preview what lies ahead as the probes prepare to enter the realm of interstellar space in our Milky Way galaxy.

The adventure began in the late 1970s when the probes took advantage of a rare alignment of outer planets for an unprecedented Grand Tour. Voyager 1 visited Jupiter and Saturn, while Voyager 2 flew past Jupiter, Saturn, Uranus and Neptune. (Voyager 2 is still the only probe to visit Uranus and Neptune.)

When pressed to name the top discoveries from those encounters, Stone pauses, not for lack of material, but rather an embarrassment of riches. "It's so hard to choose," he says.

Stone's partial list includes the discovery of volcanoes on Jupiter's moon Io; evidence for an ocean beneath the icy surface of Europa; hints of methane rain on Saturn's moon Titan; the crazily-tipped magnetic poles of Uranus and Neptune; icy geysers on Neptune's moon Triton; planetary winds that blow faster and faster with increasing distance from the sun.

"Each of these discoveries changed the way we thought of other worlds," says Stone.

In 1980, Voyager 1 used the gravity of Saturn to fling itself slingshot-style out of the plane of the solar system. In 1989, Voyager 2 got a similar assist from Neptune. Both probes set sail into the void.

Sailing into the void sounds like a quiet time, but the discoveries have continued.

Stone sets the stage by directing our attention to the kitchen sink. "Turn on the faucet," he instructs. "Where the water hits the sink, that's the sun, and the thin sheet of water flowing radially away from that point is the solar wind. Note how the sun 'blows a bubble' around itself."

There really is such a bubble, researchers call it the "heliosphere," and it is gargantuan. Made of solar plasma and magnetic fields, the heliosphere is about three times wider than the orbit of Pluto. Every planet, asteroid, spacecraft, and life form belonging to our solar system lies inside.

The Voyagers are trying to get out, but they're not there yet. To locate them, Stone peers back into the sink: "As the water [or solar wind] expands, it gets thinner and thinner, and it can't push as hard. Abruptly, a sluggish, turbulent ring forms. That outer ring is the heliosheath--and that is where the Voyagers are now."

The heliosheath is a very strange place, filled with a magnetic froth no spacecraft has ever encountered before, echoing with low-frequency radio bursts heard only in the outer reaches of the solar system, so far from home that the sun is a mere pinprick of light.

"In many ways, the heliosheath is not like our models predicted," says Stone.

In June 2010, Voyager 1 beamed back a startling number: zero. That's the outward velocity of the solar wind where the probe is now. No one thinks the solar wind has completely stopped; it may have just turned a corner. But which way? Voyager 1 is trying to figure that out through a series of "weather vane" maneuvers, in which the spacecraft turns itself in a different direction to track the local breeze. The old spacecraft still has some moves left, it seems.

No one knows exactly how many more miles the Voyagers must travel before they "pop free" into interstellar space. Most researchers believe, however, that the end is near. "The heliosheath is 3 to 4 billion miles in thickness," estimates Stone. "That means we'll be out within five years or so."

There is plenty of power for the rest of the journey. Both Voyagers are energized by the radioactive decay of a Plutonium 238 heat source. This should keep critical subsystems running through at least 2020.

After that, he says, "Voyager will become our silent ambassador to the stars."

Each probe is famously equipped with a Golden Record, literally, a gold-coated copper phonograph record. It contains 118 photographs of Earth; 90 minutes of the world's greatest music; an audio essay entitled Sounds of Earth (featuring everything from burbling mud pots to barking dogs to a roaring Saturn 5 liftoff); greetings in 55 human languages and one whale language; the brain waves of a young woman in love; and salutations from the secretary general of the United Nations. A team led by Carl Sagan assembled the record as a message to possible extraterrestrial civilizations that might encounter the spacecraft.

"A billion years from now, when everything on Earth we've ever made has crumbled into dust, when the continents have changed beyond recognition and our species is unimaginably altered or extinct, the Voyager record will speak for us," wrote Carl Sagan and Ann Druyan in an introduction to a CD version of the record.

Some people note that the chance of aliens finding the Golden Record is fantastically remote. The Voyager probes won't come within a few light years of another star for some 40,000 years. What are the odds of making contact under such circumstances?

On the other hand, what are the odds of a race of primates evolving to sentience, developing spaceflight, and sending the sound of barking dogs into the cosmos?
Expect the unexpected, indeed.

The Voyagers were built by NASA's Jet Propulsion Laboratory in Pasadena, Calif., which continues to operate both spacecraft. JPL is a division of the California Institute of Technology in Pasadena. The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate.

For more information about the Voyager spacecraft, visit: http://voyager.jpl.nasa.gov and http://www.nasa.gov/voyager .


Offline Moe Grills

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Re: NASA - Voyager 1 and 2 updates
« Reply #45 on: 04/30/2011 09:09 PM »
  They indicate that it could be five years before the Voyagers enter intersteller space.
That's cutting it pretty close I think, what with the diminishing power
output of the Voyagers, their weakening radio signal and decreasing signal-to-noise ratio. I hope they succeed.

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Re: NASA - Voyager 1 and 2 updates
« Reply #46 on: 04/30/2011 09:13 PM »
  They indicate that it could be five years before the Voyagers enter intersteller space.
That's cutting it pretty close I think, what with the diminishing power
output of the Voyagers

There should be sufficient power at least until 2020.

Offline jacqmans

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Re: NASA - Voyager 1 and 2 updates
« Reply #47 on: 06/09/2011 05:32 PM »
RELEASE: 11-174

NASA PROBES SUGGEST MAGNETIC BUBBLES RESIDE AT SOLAR SYSTEM EDGE

WASHINGTON -- Observations from NASA's Voyager spacecraft, humanity's
farthest deep space sentinels, suggest the edge of our solar system
may not be smooth, but filled with a turbulent sea of magnetic
bubbles.

While using a new computer model to analyze Voyager data, scientists
found the sun's distant magnetic field is made up of bubbles
approximately 100 million miles wide. The bubbles are created when
magnetic field lines reorganize. The new model suggests the field
lines are broken up into self-contained structures disconnected from
the solar magnetic field. The findings are described in the June 9
edition of the Astrophysical Journal.

Like Earth, our sun has a magnetic field with a north pole and a south
pole. The field lines are stretched outward by the solar wind or a
stream of charged particles emanating from the star that interacts
with material expelled from others in our corner of the Milky Way
galaxy.

The Voyager spacecraft, nearly 10 billion miles away from Earth, are
traveling in a boundary region. In that area, the solar wind and
magnetic field are affected by material expelled from other stars in
our corner of the Milky Way galaxy.

"The sun's magnetic field extends all the way to the edge of the solar
system," said astronomer Merav Opher of Boston University. "Because
the sun spins, its magnetic field becomes twisted and wrinkled, a bit
like a ballerina's skirt. Far, far away from the sun, where the
Voyagers are, the folds of the skirt bunch up."

Understanding the structure of the sun's magnetic field will allow
scientists to explain how galactic cosmic rays enter our solar system
and help define how the star interacts with the rest of the galaxy.

So far, much of the evidence for the existence of the bubbles
originates from an instrument aboard the spacecraft that measures
energetic particles. Investigators are studying more information and
hoping to find signatures of the bubbles in the Voyager magnetic
field data.

"We are still trying to wrap our minds around the implications of the
findings," said University of Maryland physicist Jim Drake, one of
Opher's colleagues.

Launched in 1977, the Voyager twin spacecraft have been on a 33-year
journey. They are en route to reach the edge of interstellar space.
NASA's Jet Propulsion Laboratory in Pasadena, Calif., built the
spacecraft and continues to operate them. The Voyager missions are a
part of the Heliophysics System Observatory, sponsored by the
Heliophysics Division of NASA's Science Mission Directorate in
Washington.

To view supporting images about the research, visit:


http://www.nasa.gov/sunearth   


Offline Cog_in_the_machine

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Re: NASA - Voyager 1 and 2 updates
« Reply #48 on: 06/09/2011 09:02 PM »
^^ Warning! Contains opinions. ^^ 

Offline Downix

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Re: NASA - Voyager 1 and 2 updates
« Reply #49 on: 06/10/2011 02:47 AM »
I am as old as these two, the first moments I was aware of space travel was from them, even before the Shuttle lifted off.  This warms my heart to see them both still going.

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Offline jacqmans

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Re: NASA - Voyager 1 and 2 updates
« Reply #50 on: 06/15/2011 05:35 PM »
June 15, 2011

Recalculating the Distance to Interstellar Space

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2011-182&cid=release_2011-182

Scientists analyzing recent data from NASA's Voyager and Cassini spacecraft have calculated that Voyager 1 could cross over into the frontier of interstellar space at any time and much earlier than previously thought. The findings are detailed in this week's issue of the journal Nature.

Data from Voyager's low-energy charged particle instrument, first reported in December 2010, have indicated that the outward speed of the charged particles streaming from the sun has slowed to zero. The stagnation of this solar wind has continued through at least February 2011, marking a thick, previously unpredicted "transition zone" at the edge of our solar system.

"There is one time we are going to cross that frontier, and this is the first sign it is upon us," said Tom Krimigis, prinicipal investigator for Voyager's low-energy charged particle instrument and Cassini's magnetospheric imaging instrument, based at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.

Krimigis and colleagues combined the new Voyager data with previously unpublished measurements from the ion and neutral camera on Cassini's magnetospheric imaging instrument. The Cassini instrument collects data on neutral atoms streaming into our solar system from the outside.

The analysis indicates that the boundary between interstellar space and the bubble of charged particles the sun blows around itself is likely between 10 and 14 billion miles (16 to 23 kilometers) from the sun, with a best estimate of approximately 11 billion miles (18 billion kilometers). Since Voyager 1 is already nearly 11 billion miles (18 billion kilometers) out, it could cross into interstellar space at any time.

"These calculations show we're getting close, but how close? That's what we don't know, but Voyager 1 speeds outward a billion miles every three years, so we may not have long to wait," said Ed Stone, Voyager project scientist, based at the California Institute of Technology in Pasadena.

Scientists intend to keep analyzing the Voyager 1 data, looking for confirmation. They will also be studying the Voyager 2 data, but Voyager 2 is not as close to the edge of the solar system as Voyager 1. Voyager 2 is about 9 billion miles (14 billion kilometers) away from the sun.

Launched in 1977, the Voyager twin spacecraft have been on a 33-year journey. They are humanity's farthest working deep space sentinels enroute to reach the edge of interstellar space. The Voyagers were built by NASA's Jet Propulsion Laboratory in Pasadena, Calif., which continues to operate both spacecraft. The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of NASA's Science Mission Directorate in Washington. JPL is managed for NASA by Caltech.

More information about Voyager is available at: http://www.nasa.gov/voyager and http://voyager.jpl.nasa.gov .


Offline racshot65

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Re: NASA - Voyager 1 and 2 updates
« Reply #51 on: 11/05/2011 09:06 PM »
Voyager 2 to Switch to Backup Thruster Set

http://www.nasa.gov/mission_pages/voyager/voyager20111105.html

Offline Kaputnik

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Re: NASA - Voyager 1 and 2 updates
« Reply #52 on: 11/06/2011 01:44 PM »
I didn't realise the thrusters got so much use. How long is the propellant expected to last? And do the roll manoeuvres consume much propellant?
Waiting for joy and raptor

Online ugordan

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Re: NASA - Voyager 1 and 2 updates
« Reply #53 on: 11/06/2011 01:51 PM »
Not pitch/yaw/roll *maneuvers* per se, but 3-axis stabilization requires maintaining specific pointing within a certain deadband.

Online Chris Bergin

Re: NASA - Voyager 1 and 2 updates
« Reply #54 on: 12/05/2011 04:35 PM »
RELEASE: 11-402

NASA'S VOYAGER HITS NEW REGION AT SOLAR SYSTEM EDGE

WASHINGTON -- NASA's Voyager 1 spacecraft has entered a new region
between our solar system and interstellar space. Data obtained from
Voyager over the last year reveal this new region to be a kind of
cosmic purgatory. In it, the wind of charged particles streaming out
from our sun has calmed, our solar system's magnetic field piles up
and higher energy particles from inside our solar system appear to be
leaking out into interstellar space.

"Voyager tells us now that we're in a stagnation region in the
outermost layer of the bubble around our solar system," said Ed
Stone, Voyager project scientist at the California Institute of
Technology in Pasadena. "Voyager is showing that what is outside is
pushing back. We shouldn't have long to wait to find out what the
space between stars is really like."

Although Voyager 1 is about 11 billion miles (18 billion kilometers)
from the sun, it is not yet in interstellar space. In the latest
data, the direction of the magnetic field lines has not changed,
indicating Voyager is still within the heliosphere, the bubble of
charged particles the sun blows around itself. The data do not reveal
exactly when Voyager 1 will make it past the edge of the solar
atmosphere into interstellar space, but suggest it will be in a few
months to a few years.

The latest findings, described today at the American Geophysical
Union's fall meeting in San Francisco, come from Voyager's Low Energy
Charged Particle instrument, Cosmic Ray Subsystem and Magnetometer.

Scientists previously reported the outward speed of the solar wind had
diminished to zero in April 2010, marking the start of the new
region. Mission managers rolled the spacecraft several times this
spring and summer to help scientists discern whether the solar wind
was blowing strongly in another direction. It was not. Voyager 1 is
plying the celestial seas in a region similar to Earth's doldrums,
where there is very little wind.

During this past year, Voyager's magnetometer also detected a doubling
in the intensity of the magnetic field in the stagnation region. Like
cars piling up at a clogged freeway off-ramp, the increased intensity
of the magnetic field shows that inward pressure from interstellar
space is compacting it.

Voyager has been measuring energetic particles that originate from
inside and outside our solar system. Until mid-2010, the intensity of
particles originating from inside our solar system had been holding
steady. But during the past year, the intensity of these energetic
particles has been declining, as though they are leaking out into
interstellar space. The particles are now half as abundant as they
were during the previous five years.

At the same time, Voyager has detected a 100-fold increase in the
intensity of high-energy electrons from elsewhere in the galaxy
diffusing into our solar system from outside, which is another
indication of the approaching boundary.

"We've been using the flow of energetic charged particles at Voyager 1
as a kind of wind sock to estimate the solar wind velocity," said Rob
Decker, a Voyager Low-Energy Charged Particle Instrument
co-investigator at the Johns Hopkins University Applied Physics
Laboratory in Laurel, Md. "We've found that the wind speeds are low
in this region and gust erratically. For the first time, the wind
even blows back at us. We are evidently traveling in completely new
territory. Scientists had suggested previously that there might be a
stagnation layer, but we weren't sure it existed until now."

Launched in 1977, Voyager 1 and 2 are in good health. Voyager 2 is 9
billion miles (15 billion kilometers) away from the sun.

The Voyager spacecraft were built by NASA's Jet Propulsion Laboratory
in Pasadena, Calif., which continues to operate both. JPL is a
division of the California Institute of Technology. The Voyager
missions are a part of the NASA Heliophysics System Observatory,
sponsored by the Heliophysics Division of the Science Mission
Directorate in Washington. For more information about the Voyager
spacecraft, visit:

http://www.nasa.gov/voyager


Online Robotbeat

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Re: NASA - Voyager 1 and 2 updates
« Reply #55 on: 12/05/2011 07:46 PM »
Awesome. Just about there to interstellar space.... Reminds me a little of Achilles and the Tortoise. :)
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

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Offline racshot65

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Re: NASA - Voyager 1 and 2 updates
« Reply #56 on: 01/18/2012 10:20 AM »
Voyager Instrument Cooling After Heater Turned off

http://www.jpl.nasa.gov/news/news.cfm?release=2012-017

Offline marshallsplace

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Re: NASA - Voyager 1 and 2 updates
« Reply #57 on: 01/18/2012 12:36 PM »
Voyager Instrument Cooling After Heater Turned off

http://www.jpl.nasa.gov/news/news.cfm?release=2012-017

"This heater shut-off is a step in the careful management of the diminishing electrical power so that the Voyager spacecraft can continue to collect and transmit data through 2025"

How amazing and "cool" are these spacecraft :)

Offline racshot65

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Re: NASA - Voyager 1 and 2 updates
« Reply #58 on: 06/15/2012 09:28 AM »
Data From NASA's Voyager 1 Point to Interstellar Future

http://www.jpl.nasa.gov/news/news.cfm?release=2012-177

Offline jacqmans

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Re: NASA - Voyager 1 and 2 updates
« Reply #59 on: 08/03/2012 10:23 PM »
 Aug. 3, 2012

Signs Changing Fast for Voyager at Solar System Edge

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2012-225&cid=release_2012-225

Two of three key signs of changes expected to occur at the boundary of interstellar space have changed faster than at any other time in the last seven years, according to new data from NASA's Voyager 1 spacecraft.

For the last seven years, Voyager 1 has been exploring the outer layer of the bubble of charged particles the sun blows around itself. In one day, on July 28, data from Voyager 1's cosmic ray instrument showed the level of high-energy cosmic rays originating from outside our solar system jumped by five percent. During the last half of that same day, the level of lower-energy particles originating from inside our solar system dropped by half. However, in three days, the levels had recovered to near their previous levels.

A third key sign is the direction of the magnetic field, and scientists are eagerly analyzing the data to see whether that has, indeed, changed direction. Scientists expect that all three of these signs will have changed when Voyager 1 has crossed into interstellar space. A preliminary analysis of the latest magnetic field data is expected to be available in the next month.

"These are thrilling times for the Voyager team as we try to understand the quickening pace of changes as Voyager 1 approaches the edge of interstellar space," said Edward Stone, the Voyager project scientist based at the California Institute of Technology, Pasadena, Calif. "We are certainly in a new region at the edge of the solar system where things are changing rapidly. But we are not yet able to say that Voyager 1 has entered interstellar space."

The levels of high-energy cosmic ray particles have been increasing for years, but more slowly than they are now. The last jump -- of five percent -- took one week in May. The levels of lower-energy particles from inside our solar system have been slowly decreasing for the last two years. Scientists expect that the lower-energy particles will drop close to zero when Voyager 1 finally crosses into interstellar space.

"The increase and the decrease are sharper than we've seen before, but that's also what we said about the May data," Stone said. "The data are changing in ways that we didn't expect, but Voyager has always surprised us with new discoveries."

Voyager 1, which launched on Sept. 5, 1977, is 11 billion miles (18 billion kilometers) from the sun. Voyager 2, which launched on Aug. 20, 1977, is close behind, at 9.3 billion miles (15 billion kilometers) from the sun.

"Our two veteran Voyager spacecraft are hale and healthy as they near the 35th anniversary of their launch," said Suzanne Dodd, Voyager project manager based at NASA's Jet Propulsion Laboratory, Pasadena. "We know they will cross into interstellar space. It's just a question of when."

The Voyager spacecraft were built by JPL, which continues to operate both. JPL is a division of the California Institute of Technology. The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in Washington.

For more information about the Voyager spacecraft, visit: http://www.nasa.gov/voyager .

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