Celestially Star-Struck

These are the little spacecraft that could.  They just keep on going.  They are nuclear-powered, true.  Not all that imposing in size; about that of a sub-compact.  But they've been extraordinarily busy in outer space.  NASA's Voyager 1 and Voyager 2 left Earth's atmosphere in 1977.  They were in a great hurry to inform science about the solar system and the outer atmosphere and stars around us.


Voyager 1 has been in travelling mode for thirty-five years.  And it is on the cusp of leaving our Solar System to enter an entirely new celestial realm and to send back data on magnetic fields and cosmic rays.  Can you imagine?  Not quite.  Astrophysicists have an idea, but even their imaginations may fall short of the trip and what those two vehicles have witnessed.

"We're anxious to get outside and find what's out there", said Ed Stone, a scientist, now 76 years of age who has worked on the space enterprise since its inception in 1977.  No one then involved in the project had any idea how long those little spacecraft would last.  They are the longest-operating spacecraft in human history.


And they are billions of kilometres from Earth.  Voyager 1 was launched toward Jupiter and Saturn.  Its current whereabouts are somewhere on the fringes of the solar system, enveloped in a huge plasma bubble.  Hot and turbulent.  A steam of charged particles from the sun make it so.  It is not an atmosphere conducive to mankind's preservation.  But the spacecraft are prevailing.

Voyager 1 is more than 17-billion kilometres' distant from the sun.  Its twin, Voyager 2, sails along behind at 14.5-billion kilometres from the sun.  Neither is reputed to have grown beards in their dotage, nor will they have picked up much dust, zipping through the stratosphere, given the friction that they have been subjected to.

Each of these spacecraft contains 68 kilobytes of computer memory.  A modest iPod at 8-gigabytes has one hundred thousand times more power.  They each also have eight-track tape recorders whereas the spacecraft of the present use digital memory systems.  These little mechanical dinosaurs seem to have no intention of failing at their mission.

Saturn

The Voyager 1 and 2 Saturn encounters occurred nine months apart, in November 1980 and August 1981. Voyager 1 is leaving the solar system. Voyager 2 completed its encounter with Uranus in January 1986 and with Neptune in August 1989, and is now also en route out of the solar system.
The Voyagers were busy in their tours of Jupiter and Saturn, sending back photos of Jupiter's big red spot and |Saturn's gleaming rings.  They beamed back erupting volcanoes on Jupiter's moon Io; icy surfaces of Europa, another moon on Jupiter and methane rain on Saturn's moon Titan.  Having done all that, Voyager 2 journeyed on to Uranus and Neptune; indefatigable.

Images Voyager Took

The Voyager 1 and 2 spacecraft explored Jupiter, Saturn, Uranus and Neptune before starting their journey toward interstellar space. Here you'll find some of those iconic images, including "The Pale Blue Dot" - famously described by Carl Sagan - and what are still the only up-close images of Uranus and Neptune.  › view images

Voyager 2 represents the only spacecraft to fly by Uranus and Neptune; Voyager 2 catapulted itself toward the edge of the solar system using Saturn as a gravitational slingshot.  "Time after time, Voyager revealed unexpected - kind of counterintuitive - results, which means we have a lot to learn", said Dr. Stone, Voyager's chief scientist, professor of physics at the California Institute of Technology.