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Rae Paoletta • Mar 03, 2022

The best space pictures from the Voyager 1 and 2 missions

Launched in 1977, NASA’s Voyager 1 and 2 missions provided an unprecedented glimpse into the outer solar system — a liminal space once left largely to the imagination. The spacecraft provided views of worlds we’d never seen before, and in some cases, haven’t seen much of since.

The Voyager probes were launched about two weeks apart and had different trajectories, like two tour guides at the same museum. Only Voyager 2 visited the ice giants — Uranus and Neptune — for example.

The Voyagers hold a unique position in the pantheon of space history because they’re still making it; even right now, Voyagers 1 and 2 are the only functioning spacecraft in interstellar space. Both hold a Golden Record that contains sights and sounds of Earth in case alien life were to find one of the spacecraft.

As the Voyager missions voyage on, it’s good to look back at how they captured our solar system before leaving it.

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Voyager: 15 incredible images of our solar system captured by the twin probes (gallery)

The twin probes have captured some remarkable images of our cosmic neighborhood.

NASA's twin probes Voyager 1 and Voyager 2 have captured some truly remarkable images of our solar system and are currently roaming through interstellar space. 

Despite its name Voyager 2 launched before Voyager 1 , when it lifted off from Cape Canaveral Space Launch Complex 41 aboard a Titan IIIE-Centaur on Aug. 20, 1977. Voyager 1 followed suit about two weeks later on Sept. 5. 

While Voyager 1 primarily focused on Jupiter and Saturn , Voyager 2 visited both gas giants and then ventured on to Uranus and Neptune . But the duo didn't stop there. Voyager 1 officially entered interstellar space on Aug. 25, 2012, while Voyager 2 entered on Nov. 5, 2018. The pair continue to journey through the cosmos and have enough power and fuel to keep scientific instruments running until at least 2025, according to NASA . 

Here we celebrate the achievements of both Voyager 1 and Voyager 2 with some incredible images captured by the pair. 

This image was taken when NASA's Voyager 1 spacecraft zoomed toward Jupiter in January and February 1979, capturing hundreds of images during its approach, including this close-up of swirling clouds around Jupiter's Great Red Spot . 

This image of the Earth and moon are in a single frame. Voyager was the first spacecraft to achieve this and captured the iconic image on Sept. 18, 1977, by Voyager 1 when it was 7.25 million miles from Earth. The moon is at the top of the picture and beyond the Earth as viewed by Voyager. 

Color composite by Voyager 2 showing Jupiter's faint ring system. Images captured in July 1979. 

A Voyager 1 image of Jupiter's moon Io showing the active plume of the volcano Loki. The heart-shaped feature southeast of Loki consists of fallout deposits from the active plume Pele. The images that make up this mosaic were taken from an average distance of approximately 340,000 miles (490,000 kilometers) from the moon. 

Layers of haze covering Saturn's moon Titan are seen in this image taken by Voyager 1 on Nov. 12, 1980, at a range of 13,700 miles (22,000 km). This false-color image shows the details of the haze that covers Titan. The upper level of the thick aerosol above the moon's limb appears orange. 

This view of Uranus was recorded by Voyager 2 on Jan. 25, 1986, as the spacecraft left the planet behind and set forth on the cruise to Neptune. Even at this extreme angle, Uranus retains the pale blue-green color seen by ground-based astronomers and recorded by Voyager during the historic encounter. 

This Voyager 2 high-resolution color image provides obvious evidence of vertical relief in Neptune's bright cloud streaks. These clouds were observed at a latitude of 29 degrees north near Neptune's east terminator, the "line" on a planet where daylight meets darkness. 

Global color mosaic of Triton , taken in 1989 by Voyager 2 during its flyby of the Neptune system. The color was synthesized by combining high-resolution images taken through orange, violet and ultraviolet filters; these images were displayed as red, green and blue images and combined to create this color version. 

Saturn and three of its moons, Tethys, Dione and Rhea, seen by a Voyager spacecraft on Aug. 4, 1982, from a distance of 13 million miles (21 million km). 

This narrow-angle color image of the Earth, dubbed the "Pale Blue Dot," is a part of the first ever 'portrait' of the solar system taken by Voyager 1. The spacecraft acquired a total of 60 frames for a mosaic of the solar system from a distance of more than 4 billion miles (6 billion km) from Earth and about 32 degrees above the ecliptic, which is the plane that contains most of the planets of the solar system. 

Voyager 1 took photos of Jupiter and two of its satellites (Io, left, and Europa ).

Enhanced color view of Saturn's ring system captured by Voyager 2 on Aug. 17, 1981, at a distance of 5.5 million miles (8.9 million km). The color variations between the rings possibly indicate variations in chemical composition from one part of Saturn's ring system to another.  

Close-up of the surface of Jupiter's moon Europa captured by Voyager 2 at a distance of 152,000 miles (246,000 km). 

Voyager 2 captured this image of Neptune's rings on Aug. 26, 1989, from a distance of 175,000 miles (280,000 km).  

A false-color image of Callisto captured on July 7, 1979, by Voyager 2 at a distance of about 677,000 miles (1.09 million km). Callisto is the second largest moon of Jupiter and is the most heavily cratered of the Galilean satellites. 

Daisy Dobrijevic joined Space.com in February 2022 having previously worked for our sister publication All About Space magazine as a staff writer. Before joining us, Daisy completed an editorial internship with the BBC Sky at Night Magazine and worked at the National Space Centre in Leicester, U.K., where she enjoyed communicating space science to the public. In 2021, Daisy completed a PhD in plant physiology and also holds a Master's in Environmental Science, she is currently based in Nottingham, U.K. Daisy is passionate about all things space, with a penchant for solar activity and space weather. She has a strong interest in astrotourism and loves nothing more than a good northern lights chase! 

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What If We Turned On Voyager 1’s Camera?

February 22, 2023

This is the famous pale blue dot image taken by Voyager 1 , showing our Earth as a tiny pixel, 6 billion kilometers away. This picture was taken before many of you were even born , but the elements and materials that made us are all contained in that tiny blue dot we call home. But this date is significant.

Just 34 minutes after this picture was taken, the cameras were switched off forever , leaving Voyager 1 completely blind. Since then, the spacecraft has become the furthest man-made object in space, now at a point 24 billion kilometers from Earth.

But why were the cameras turned off? And what would it take to turn them back on?

The Voyager space probes have broken so many records during their time in space. Not only are they the furthest objects in space , but they’ve also been operating for the longest amount of time, over 45 years.

It’s incredible to think that after all that time spent in the harsh environment of space, the computers and systems that were designed here on Earth in the 70’s are still functioning. Voyager is powered by a radioisotope thermoelectric generator (RTG). This is basically a nuclear battery that can last for a very long time. These are very common on spacecraft and it’s why Voyager has been able to run continuously for over 45 years.

Voyager 1 was filled with technology that was way ahead of its time, and a perfect example of that is the camera system.

Voyager 1 camera technology

Voyager 1 has two vidicon cameras onboard which are essentially very early television cameras using analog to digital technology. They had an effective resolution of 800 by 800 pixels and captured 8 bit images in grayscale.

One had a wide angle lens for capturing the planets in full detail as the probe passed close by. The other had a narrow angle lens which was zoomed in and could capture the smaller details of each planet it observed and of course, look back at our solar system as it grew smaller and smaller on the horizon. As always, fitting stuff onto a spacecraft is a complex process, as everything has to be made as small and as light as possible. These cameras didn´t produce the sharpest images and they were only black and white.

However, before the light reached these cameras, it went through an optics system that allowed it to form colored images.

This was a filter wheel that contained violet, blue, green and orange filters. Voyager would take multiple images of its subject using each of its filters. As light passed through the filter, it would only allow light from that color to pass through, the other colors would be absorbed.

The images were still taken in grayscale, but each image would have areas with different amounts of brightness, where the light was more sensitive to a certain color. Once these images were sent to Earth, they were saturated with their respective filter color and combined to form a full color image.

This is essentially how the human eye works, since our eyes have three color sensing cones: red, green and blue, which are combined to give us vision with a range of colors. But with Voyager, the real magic happens inside the vidicon tube.

Voyager´s Vidcon Tube

After the light passes through the lens and filter wheel, it enters into the vidicon tube. The first thing the photons hit is a see-through faceplate, made from a layer of tin-oxide, which has a photoconductive target plate just behind it. When the photons hit the target plate, free electrons are created.

The higher the intensity of light on a given point, the more free electrons are created. These free electrons are then attracted to the faceplate, leaving behind gaps on the target plate. After this, a cathode at the back of the tube fires electrons towards the target plate to scan the image.

These electrons reach the target plate and fill in the gaps, creating an electric current. This signal contains the image data and can now be transmitted back to Earth.

Sending pictures back to Earth

We’ve seen how Voyager’s cameras convert the light into a signal, but what happens after that? This wasn´t an ordinary film camera where each picture could be processed here on Earth. Each image that Voyager captured would take up around 5 million bits of information – or just over half a megabyte.

This doesn’t sound like a lot by today’s standards, but when your spacecraft is billions of kilometers away, sending that data back is extremely difficult. Back in the day when Voyager 1 was much closer, it had a maximum data rate of around 115,000 bits per second. At this rate, it would take about 43 seconds to send an entire image back to Earth.

Now, the data rate is only around 160 bits per second, meaning it would take over 8 hours just to transmit one image. On top of that, Voyager 1 is now 23 billion kilometers away, so that signal would actually take 21 hours to reach us.

Since the camera can produce an image much faster than it can transmit the data, the signal from the vidicon camera is stored onto magnetic tape. This is basically an early analog harddrive. This data builds up over time and can be transmitted whenever Voyager 1 has a good line of communication with Earth. But why hasn’t Voyager’s camera been turned on in over 30 years?

Turning on the camera

To answer this, we need to look at where Voyager 1 was when it took its last picture. The famous pale blue dot image was taken from a point in space 6 billion kilometers from Earth. At this point, the spacecraft was so far away, that everything appeared as a tiny dot.

The spacecraft was also heading on a path that would eventually make it the first spacecraft to leave the solar system and reach interstellar space. So in order to know when this happened, the team wanted to prioritize the instruments that would detect interstellar plasma, a sign that Voyager 1 had left our solar system.

But Voyager 1 was already 13 years old at this point and it still had decades to go before reaching interstellar space. So, in order to still be talking with the spacecraft at that point, the engineers needed to extend its lifetime drastically.

Voyager´s power source

Like many spacecraft, Voyager 1 is powered by an RTG, which takes the heat from a radioactive material and turns it into electricity. Every year, the power output decays by about 4 Watts – and now, Voyager 1 is only producing 57% of its initial power output.

The camera system alone uses just over 40 watts of power. And so to buy the spacecraft more time, the team began shutting down various instruments onboard Voyager to reduce its power consumption.

To save memory, the team also removed the software onboard Voyager, which was responsible for operating the camera. The computers and software here on Earth that were used to analyze the images don’t even exist anymore.

And due to the cameras and their heaters being exposed to the harsh conditions of outer space for several decades , it’s likely that they wouldn’t be able to function any more. But assuming the cameras were still in good condition, what would they see if they were turned back on?

Many think that Voyager 1 is so far from the sun that it will be in complete darkness, but this is not true. Despite now being 23 billion kilometers away, the light from the sun is still 16 times brighter than the Moonlight here on Earth, so it’s definitely enough to read a book.

However, there just isn’t anything interesting or big enough around Voyager to capture on camera. If Voyager took an image today, it would be dark – but you’d still see the sun and some planets as tiny faint pixels. Perhaps the most incredible thing is that despite traveling 23 billion kilometers, the star constellations in our sky would look exactly the same.

If Voyager wanted a different perspective of our galaxy, it would need to travel thousands of light years just to see a slight shift in the stars. Voyager 1 will eventually achieve this, millions of years after we are gone and long after we have lost contact with the space probe.

Ewan Cunningham

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Trump target of assassination attempt; says he was shot in ear at rally

BUTLER, Pa. — Former President Donald Trump was injured Saturday in an assassination attempt when a gunman opened fire at his campaign rally, killing one spectator and bloodying Trump’s ear.

The shooter, who appeared to take an elevated position on a rooftop outside the venue, is dead. Another two spectators were critically injured. Trump’s campaign said he was safe. 

FBI Special Agent Kevin Rojek said during a midnight press conference that law enforcement is not prepared to identify the suspected shooter yet. Rojek said investigators have not yet identified a motive.

In a harrowing and chaotic scene, Trump was about six minutes into his remarks in western Pennsylvania when pops of gunfire rang out. The Republican presidential contender grabbed his right ear and then got to the floor, where he was immediately swarmed by Secret Service agents who piled on top of him to protect him.

The agents then helped Trump to his feet, surrounded him, and rushed him off stage and to a waiting vehicle. Trump — with blood on the side of his head and his ear — repeatedly pumped his fist in the air and waved as the crowd cheered.

Trump said in a post on Truth Social about 2½ hours later that a bullet “pierced the upper part of my right ear.”

“I knew immediately that something was wrong in that I heard a whizzing sound, shots, and immediately felt the bullet ripping through the skin,” Trump wrote. “Much bleeding took place, so I realized then what was happening.”

Trump thanked law enforcement in his online statement and extended condolences to the families of the people killed and injured.

“It is incredible that such an act can take place in our Country,” he wrote.

The shots were fired from outside the Secret Service security perimeter for the rally, according to three senior U.S. law enforcement officials.

Reporters saw smoke and heard what they initially thought were fireworks before everyone ducked and law enforcement encircled Trump.

Screams rang out from the audience as the scene unfolded.

Pennsylvania Gov. Josh Shapiro said in a statement shortly after 11 p.m. that Trump “has now left the Butler area.”

Follow live updates on the Trump rally shooting

A doctor attending the event told NBC News that he saw a man suffer a gunshot wound to the head and helped carry him from the site of the rally. Speaking in a parking lot near the event, a mother and her son who were attending the rally told NBC News that they saw people in the crowd who were injured and carried away. And in the hours after the shooting, Rep. Ronny Jackson, R-Texas, said in an interview on Fox News that his nephew was grazed on his neck by a bullet at the rally.

People remained at the scene for 10 to 15 minutes after Trump was taken away, after which they were told it was an active crime scene and all attendees were escorted out.

Trump spokesperson Steven Cheung said Trump “thanks law enforcement and first responders for their quick action during this heinous act.”

“He is fine and is being checked out at a local medical facility,” Cheung said. “More details will follow.”

Trump senior advisers and leaders of the Republican National Committee released a statement later Saturday night saying that the former president “looks forward to joining you all in Milwaukee as we proceed with our convention to nominate him to serve as the 47th President of the United States.”

The Republican National Convention, where Trump is set to officially become the GOP presidential nominee, is set to begin on Monday.

FBI leads investigation

The FBI is leading the investigation into the shooting, according to a statement from the bureau. Agents are working alongside U.S. Secret Service, as well as state and local law enforcement.

Federal investigators have tentatively identified the suspected shooter, who was a male from Pennsylvania, according to five senior U.S. law enforcement officials briefed on the matter.

Law enforcement is working to verify the suspect’s identity using his DNA because the suspect did not have identification on him during the shooting, officials said at the late Saturday press conference in Butler.

In the aftermath of the shooting, the FBI deployed investigative agents, bomb technicians, and evidence response personnel. Intelligence analysts are also working to identify the shooter.

Officials also asked that witnesses to the shooting contact the FBI.

There is no sign that the attack has any link to a foreign actor, a U.S. official said.

House Speaker Mike Johnson, R-La., said in a statement on X that he has been briefed by law enforcement. He condemned the attack as a “horrific act of political violence at a peaceful campaign rally,” saying it “has no place in this country and should be unanimously and forcefully condemned.”

Johnson said in a later post that the House would conduct a “full investigation of the tragic events today.”

House Oversight Committee Chair James Comer, R-Ky., said in a statement on X that he was “calling on Secret Service Director Kimberly Cheatle to appear for a hearing.”

In a letter to Cheatle, Comer requested that she voluntarily appear at a committee hearing on July 22.

Biden, political world react

President Joe Biden spoke with Trump later on Saturday, according to a White House official. He also spoke with Shapiro and Butler Mayor Bob Dandoy. 

In remarks delivered from Delaware, Biden called the attack “sick” and thanked law enforcement in remarks delivered on camera.

“There’s no place in America for this kind of violence. It’s sick. It’s sick,” Biden said. “It’s one of the reasons why we have to unite this country. We cannot allow for this to be happening.”

“Everybody must condemn it,” Biden added.

Asked by a reporter whether he believed that the attack on Trump was an assassination attempt, Biden responded that he didn't "know enough" to say at the time.

"I have an opinion, but I don't have any facts," he said, adding that he wanted to gather all of the facts first.

Biden also said in a statement that he is praying for Trump. He said he has been briefed on the shooting.

"I’m grateful to hear that he’s safe and doing well. I’m praying for him and his family and for all those who were at the rally, as we await further information," Biden's statement said. "Jill and I are grateful to the Secret Service for getting him to safety. There’s no place for this kind of violence in America. We must unite as one nation to condemn it."

Biden learned about the attack when he was coming out of church services, according to a person familiar with the timeline of events. He wanted to address the nation as soon as he was fully briefed, the source added.

Vice President Kamala Harris has also been briefed, she said in a statement.

She said she her husband, Doug Emhoff, "are relieved that he is not seriously injured. We are praying for him, his family, and all those who have been injured and impacted by this senseless shooting."

She added that "violence such as this has no place in our nation," urging everyone to "condemn this abhorrent act."

In the minutes after the incident unfolded, politicians began posting on social media that they were praying for Trump, including three vice presidential contenders, Sen. JD Vance , R-Ohio, Sen. Marco Rubio , R-Fla., and North Dakota Gov. Doug Burgum .

Donald Trump Jr., one of the president's children, wrote on X that his father will "never stop fighting to Save America." His message was accompanied by a photo of his father pumping his fist with blood on his face.

Democratic leaders also released statements expressing horror.

"I am horrified by what happened at the Trump rally in Pennsylvania and relieved that former President Trump is safe," Senate Majority Leader Chuck Schumer, D-N.Y., said o n X . "Political violence has no place in our country."

Shapiro, Pennsylvania's Democratic governor, condemned the attack on X, as well.

"Violence targeted at any political party or political leader is absolutely unacceptable," Shapiro said . "It has no place in Pennsylvania or the United States."

Shapiro added that he has been briefed on the situation and that state police were on the scene, working with federal and local partners.

Independent presidential candidate Robert F. Kennedy Jr. urged Americans to pray for Trump.

“Now is the time for every American who loves our country to step back from the division, renounce all violence, and unite in prayer for President Trump and his family,” Kennedy said .  

Former Rep. Gabby Giffords, D-Ariz., who was shot in 2011, released a statement condemning political violence.

“Political violence is terrifying. I know,” she said. “I’m holding former president Trump, and all those affected by today’s indefensible act of violence in my heart. Political violence is un-American and is never acceptable — never.”

House Majority Leader Steve Scalise, R-La., who was shot and injured in 2017 when a gunman opened fire on Republicans during a baseball practice, condemned "incendiary rhetoric" ahead of the attack about a second Trump term being a threat to the country.

"That incendiary rhetoric needs to stop, because all it takes is one person who’s just unhinged to hear that and go act on it, and think that that’s their signal to go take somebody out," Scalise said during a Fox News interview.

Trump’s campaign is in a “complete communications lockdown,” according to a message sent to staff members by James Blair, the political director for the Trump campaign and the Republican National Committee.

"Everything is OK,” Blair wrote. “We have no details to share at this time but will follow up soon with more information.”

A Biden campaign official told NBC News that the campaign is also "pausing all outbound communications and working to pull down our television ads as quickly as possible.”

This is a breaking news story and will continue to be updated.

Dasha Burns and Jake Traylor are reporting from Butler, Pa.; Megan Lebowitz from Washington, D.C.; and Chloe Atkins, Tom Winter and Jonathan Dienst from New York City.

Dasha Burns is a correspondent for NBC News.

Jake Traylor is a 2024 NBC News campaign embed.

Megan Lebowitz is a politics reporter for NBC News.

Chloe Atkins reports for the NBC News Investigative Unit, based in New York. She frequently covers crime and courts, as well as the intersection of reproductive health, politics and policy.

Tom Winter is a New York-based correspondent covering crime, courts, terrorism and financial fraud on the East Coast for the NBC News Investigative Unit.

Jonathan Dienst is chief justice contributor for NBC News and chief investigative reporter for WNBC-TV in New York.

• The Contents
• The Making of
• Where Are They Now
• Frequently Asked Questions
• Q & A with Ed Stone

golden record

Where are they now.

• frequently asked questions
• Q&A with Ed Stone

Did You Know?

The Voyager mission was officially approved in May 1972. Through the dedicated efforts of many skilled personnel for over three decades, the Voyagers have returned knowledge about the outer planets that had not existed in all of the preceding history of astronomy and planetary science. The Voyager spacecrafts are still performing like champs.

It must come as no surprise that there are many remarkable, "gee-whiz" facts associated with the various aspects of the Voyager mission. These tidbits have been summarized below in appropriate categories. Several may seem difficult to believe, but they are all true and accurate.

Overall Mission

The total cost of the Voyager mission from May 1972 through the Neptune encounter (including launch vehicles, radioactive power source (RTGs), and DSN tracking support) is 865 million dollars. At first, this may sound very expensive, but the fantastic returns are a bargain when we place the costs in the proper perspective. It is important to realize that:

• on a per-capita basis, this is only 8 cents per U.S. resident per year, or roughly half the cost of one candy bar each year since project inception. the entire cost of Voyager is a fraction of the daily interest on the U.S. national debt.
• A total of 11,000 workyears was devoted to the Voyager project through the Neptune encounter. This is equivalent to one-third the amount of effort estimated to complete the great pyramid at Giza to King Cheops.

A total of five trillion bits of scientific data had been returned to Earth by both Voyager spacecraft at the completion of the Neptune encounter. This represents enough bits to fill more than seven thousand music CDs.

The sensitivity of our deep-space tracking antennas located around the world is truly amazing. The antennas must capture Voyager information from a signal so weak that the power striking the antenna is only 10 exponent -16 watts (1 part in 10 quadrillion). A modern-day electronic digital watch operates at a power level 20 billion times greater than this feeble level.

Voyager Spacecraft

Each Voyager spacecraft comprises 65,000 individual parts. Many of these parts have a large number of "equivalent" smaller parts such as transistors. One computer memory alone contains over one million equivalent electronic parts, with each spacecraft containing some five million equivalent parts. Since a color TV set contains about 2500 equivalent parts, each Voyager has the equivalent electronic circuit complexity of some 2000 color TV sets.

Like the HAL computer aboard the ship Discovery from the famous science fiction story 2001: A Space Odyssey, each Voyager is equipped with computer programming for autonomous fault protection. The Voyager system is one of the most sophisticated ever designed for a deep-space probe. There are seven top-level fault protection routines, each capable of covering a multitude of possible failures. The spacecraft can place itself in a safe state in a matter of only seconds or minutes, an ability that is critical for its survival when round-trip communication times for Earth stretch to several hours as the spacecraft journeys to the remote outer solar system.

Both Voyagers were specifically designed and protected to withstand the large radiation dosage during the Jupiter swing-by. This was accomplished by selecting radiation-hardened parts and by shielding very sensitive parts. An unprotected human passenger riding aboard Voyager 1 during its Jupiter encounter would have received a radiation dose equal to one thousand times the lethal level.

The Voyager spacecraft can point its scientific instruments on the scan platform to an accuracy of better than one-tenth of a degree. This is comparable to bowling strike-after-strike ad infinitum, assuming that you must hit within one inch of the strike pocket every time. Such precision is necessary to properly center the narrow-angle picture whose square field-of-view would be equivalent to the width of a bowling pin.

To avoid smearing in Voyager's television pictures, spacecraft angular rates must be extremely small to hold the cameras as steady as possible during the exposure time. Each spacecraft is so steady that angular rates are typically 15 times slower than the motion of a clock's hour hand. But even this was not steady enough at Neptune, where light levels are 900 times fainter than those on Earth. Spacecraft engineers devised ways to make Voyager 30 times steadier than the hour hand on a clock.

The electronics and heaters aboard each nearly one-ton Voyager spacecraft can operate on only 400 watts of power, or roughly one-fourth that used by an average residential home in the western United States.

A set of small thrusters provides Voyager with the capability for attitude control and trajectory correction. Each of these tiny assemblies has a thrust of only three ounces. In the absence of friction, on a level road, it would take nearly six hours to accelerate a large car up to a speed of 48 km/h (30 mph) using one of the thrusters.

The Voyager scan platform can be moved about two axes of rotation. A thumb-sized motor in the gear train drive assembly (which turns 9000 revolutions for each single revolution of the scan platform) will have rotated five million revolutions from launch through the Neptune encounter. This is equivalent to the number of automobile crankshaft revolutions during a trip of 2725 km (1700 mi), about the distance from Boston,MA to Dallas,TX.

The Voyager gyroscopes can detect spacecraft angular motion as little as one ten-thousandth of a degree. The Sun's apparent motion in our sky moves over 40 times that amount in just one second.

The tape recorder aboard each Voyager has been designed to record and playback a great deal of scientific data. The tape head should not begin to wear out until the tape has been moved back and forth through a distance comparable to that across the United States. Imagine playing a two-hour video cassette on your home VCR once a day for the next 33 years, without a failure.

The Voyager magnetometers are mounted on a frail, spindly, fiberglass boom that was unfurled from a two-foot-long can shortly after the spacecraft left Earth. After the boom telescoped and rotated out of the cannister to an extension of nearly 13 meters (43 feet), the orientations of the magnetometer sensors were controlled to an accuracy better than two degrees.

Each Voyager used the enormous gravity field of Jupiter to be hurled on to Saturn, experiencing a Sun-relative speed increase of roughly 35,700 mph. As total energy within the solar system must be conserved, Jupiter was initially slowed in its solar orbit---but by only one foot per trillion years. Additional gravity-assist swing-bys of Saturn and Uranus were necessary for Voyager 2 to complete its Grand Tour flight to Neptune, reducing the trip time by nearly twenty years when compared to the unassisted Earth-to-Neptune route.

The Voyager delivery accuracy at Neptune of 100 km (62 mi), divided by the trip distance or arc length traveled of 7,128,603,456 km (4,429,508,700 mi), is equivalent to the feat of sinking a 3630 km (2260 mi) golf putt, assuming that the golfer can make a few illegal fine adjustments while the ball is rolling across this incredibly long green.

Voyager's fuel efficiency (in terms of mpg) is quite impressive. Even though most of the launch vehicle's 700 ton weight is due to rocket fuel, Voyager 2's great travel distance of 7.1 billion km (4.4 billion mi) from launch to Neptune resultsed in a fuel economy of about 13,000 km per liter (30,000 mi per gallon). As Voyager 2 streaked by Neptune and coasts out of the solar system, this fuel economy just got better and better!

The resolution of the Voyager narrow-angle television cameras is sharp enough to read a newspaper headline at a distance of 1 km (0.62 mi).

Pele, the largest of the volcanoes seen on Jupiter's moon Io, is throwing sulfur and sulfur-dioxide products to heights 30 times that of Mount Everest, and the fallout zone covers an area the size of France. The eruption of Mount St. Helens was but a tiny hiccup in comparison (admittedly, Io's surface-level gravity is some six times weaker than that of Earth).

The smooth water-ice surface of Jupiter's moon Europa may hide an ocean beneath, but some scientists believe any past oceans have turned to slush or ice. In 2010: Odyssey Two, Arthur C. Clarke wraps his story around the possibility of life developing within the oceans of Europa.

The rings of Saturn appeared to the Voyagers as a dazzling necklace of 10,000 strands. Trillions of ice particles and car-sized bergs race along each of the million-kilometer-long tracks, with the traffic flow orchestrated by the combined gravitational tugs of Saturn, a retinue of moons and moonlets, and even nearby ring particles. The rings of Saturn are so thin in proportion to their 171,000 km (106,000 mi) width that, if a full-scale model were to be built with the thickness of a phonograph record the model would have to measure four miles from its inner edge to its outer rim. An intricate tapestry of ring-particle patterns is created by many complex dynamic interactions that have spawned new theories of wave and particle motion.

Saturn's largest moon Titan was seen as a strange world with its dense atmosphere and variety of hydrocarbons that slowly fall upon seas of ethane and methane. To some scientists, Titan, with its principally nitrogen atmosphere, seemed like a small Earth whose evolution had long ago been halted by the arrival of its ice age, perhaps deep-freezing a few organic relics beneath its present surface.

The rings of Uranus are so dark that Voyager's challenge of taking their picture was comparable to the task of photographing a pile of charcoal briquettes at the foot of a Christmas tree, illuminated only by a 1 watt bulb at the top of the tree, using ASA-64 film. And Neptune light levels will be less than half those at Uranus.

Through the ages, astronomers have argued without agreeing on where the solar system ends. One opinion is that the boundary is where the Sun’s gravity no longer dominates – a point beyond the planets and beyond the Oort Cloud. This boundary is roughly about halfway to the nearest star, Proxima Centauri. Traveling at speeds of over 35,000 miles per hour, it will take the Voyagers nearly 40,000 years, and they will have traveled a distance of about two light years to reach this rather indistinct boundary.

But there is a more definitive and unambiguous frontier, which the Voyagers will approach and pass through. This is the heliopause, which is the boundary area between the solar and the interstellar wind. When Voyager 1 crosses the solar wind termination shock, it will have entered into the heliosheath, the turbulent region leading up to the heliopause. When the Voyagers cross the heliopause, hopefully while the spacecraft are still able to send science data to Earth, they will be in interstellar space even though they will still be a very long way from the “edge of the solar system”. Once Voyager is in interstellar space, it will be immersed in matter that came from explosions of nearby stars. So, in a sense, one could consider the heliopause as the final frontier.

Barring any serious spacecraft subsystem failures, the Voyagers may survive until the early twenty-first century (~ 2025), when diminishing power and hydrazine levels will prevent further operation. Were it not for these dwindling consumables and the possibility of losing lock on the faint Sun, our tracking antennas could continue to "talk" with the Voyagers for another century or two!