By Rebekah Williams
Spacecraft launched in 1977 is first human-made object to leave Solar System
On Thursday, Sept. 12, NASA officially announced that the spacecraft Voyager 1 is the first man-made object to leave our solar system.
Launched in 1977, the same year that Star Wars was first released, both Voyager 1 and Voyager 2 are both still traveling throughout outer space, transmitting signals back to Earth.
Both spacecrafts visited Saturn and Jupiter, sending home never-before-seen pictures of the giant, gassy planets.
From there, however, their journeys parted ways.
While Voyager 2 took a circuitous path to visit Uranus and Neptune, Voyager 1 harnessed energy from Saturn to propel itself past Pluto. Together, the two have discovered 23 previously unknown moons.
Each craft carried phonographs from the 1970s containing recordings of human music and greetings in 56 languages along with natural earthen sounds.
Voyager 1 is the size of a small car, travels at a speed of 38,000 miles per hour and has thus far covered over 11.7 billion miles.
Until 1990, it sent pictures home to Earth, but has since stopped in order to conserve energy, and because there is not much to see.
Interestingly enough, NASA’s announcement on Sept. 12 came more than a year after the spacecraft actually left the Solar System. Due to a lack of a “leaving your solar system. Please come back soon!” sign, it was difficult to determine where exactly Voyager 1 was located.
However, NASA scientists have been noticing clues for a few months now. For one, charged particles from the sun seemed to suddenly vanish. For another, there seemed to be a spike in galactic cosmic rays.
The tell-tale sign, according to many scientists, would be the spacecraft recording a change in the direction of the magnetic field.
While waiting for this final determining clue, a chance solar eruption occurred.
Voyager 1 detected the eruption, and its plasma wave instrument reflected that the plasma surrounding the spacecraft is 40 times denser than it was when known to be within the heliosphere, the outer bounds of our solar system.
NASA has taken this as the final bit of evidence they needed. They have officially declared their calculations that Voyager 1 left the solar system on Aug. 25, 2012.
Many scientists are still wary of this declaration. Lennard Fisk, a space science professor at the University of Michigan and former NASA associate administrator, said, “It is premature to judge.”
Scientists like Fisk are still waiting for a change in the direction of the magnetic field before they will jump to any conclusions.
Despite these objections, NASA seems to have its mind made up. Dr. Edward C. Stone, NASA’s top Voyager expert, has been working on the project since 1972.
He reported, “This is historic stuff, a bit like the first exploration of Earth, and we had to look at the data very, very carefully.”
Voyager 2 is also expected to eventually exit the solar system. Both Voyager 1 and 2 will continue to coast past other stars, being acted upon by gravity. Voyager 1 is expected to keep sending data back to Earth until about the year 2025.
In roughly 40,000 years, long after its ability to contact Earth is lost, Voyager 1 is expected to reach the star AC+79388 in the constellation of Camelopardalis.
NASA’s Suzanne Dodd, the mission project manager, has called Voyager 1 “the little spacecraft that could.”