Happy Belated Birthday, Voyager 1
Monday, September 10th, 2012
by AJ Plunkett
September 5th marked the 35th anniversary of the launch of the space probe Voyager 1. Now, with each passing day it gets closer to its final mission, which, according to NASA, is to “break on through to the other side,” into interstellar space. (Cue The Doors.)
In early August, NASA reported that two-of-three key changes (that scientists expect to signal the spacecraft’s travel beyond the solar system’s heliopause) have changed faster than at any other time in the last seven years.
Them Cosmic Rays
Scientists are studying changes both in high-energy cosmic rays (originating from outside our solar system), and changes in the level of low-energy particles (from inside our solar system). They’re also looking at changes in the direction of the magnetic field.
According to data received from Voyager on July 26, high-energy cosmic rays jumped by five percent and low-energy particles fifty percent. However, three days later, the levels had returned to where they were previously. So, scientists are now “eagerly analyzing” the magnetic field readings.
Because similar readings were recorded in May, NASA researchers are trying not to get too excited.
“The increase and the decrease are sharper than we’ve seen before, but that’s also what we said about the May date,” said Edward Stone, a Voyager project scientist at the California Institute of Technology in Pasadena, California. “The data are changing in ways we didn’t expect, but Voyager has always surprised us with new discoveries.”
The Never-Ending Mission?
The twin spacecraft were designed to explore Jupiter, Saturn, Uranus, and Neptune during their original mission, which was expected to last only five years.
Eventually, the spacecraft were sent further along to check out Pluto and other bodies, until finally the decision was made to send them toward interstellar space to see how far they could go.
Two Paths to Go By
Voyager 1 launched on Sept. 5, 1977, and its sensors show that it is about 18 billion kilometers from the sun. And its companion spacecraft, Voyager 2, which launched on Aug. 20, 1977, is only 3 billion kilometers or so behind its twin.
Despite their long journey, the spacecraft are “in great shape,” said NASA’s project manager Suzanne Dodd. The Voyager project team anticipates that whenever the pair reach interstellar space, they will continue to transmit data back to Earth through 2020 and perhaps even longer.
Where will they end up? At this rate, who knows? But, we can say this: “Happy Belated Birthday, Voyager — wherever you are.”
AJ Plunkett is a freelance writer in Virginia with experience in covering defense and aerospace industries as well as the military. AJ blogs via Contently.com.