New evidence from NASA suggests Voyager-1, launched in 1977, may lastly be leaving the solar system — something no spacecraft has ever accomplished.
For a lot more than a month, the space environment about Voyager-1 has been changing. The small spacecraft is becoming hit by rising numbers of high-energy particles, suggesting it’s in a region outside the sun’s influence where there are a lot more cosmic rays.
Our sun sends out particles known as solar wind that continue far past the most distant planets. It also has an huge magnetic field. Astronomers generally define our solar system as the region exactly where the solar wind and magnetic field extend.
NASA has been estimating for years that Voyager-1 will reach the edge of the solar system about 2014. It is 17.9 billion kilometres from Earth, just over 120 times the distance from the Earth to the sun.
Data from NASA’s Goddard Space Flight Center show that for most of the past year, Voyager-1 was becoming hit an average of 1.7 times a second by high-energy particles such as protons. About the beginning of May, that rate started climbing steadily. It is about two particles per second now.
The implication is that much more cosmic rays are hitting the spacecraft due to the fact there’s less solar influence to deflect them, “in which case Voyager-1 has reached the magnetopause boundary (i.e. where the magnetic field ends) and thus the boundary of the Solar System,” astronomer Nick Suntzeff of Texas A&M University wrote in an e mail.
This alone is not final proof the actual nature and place of the edge of the solar system are still unknown. But some astronomers are suggesting the boost in particles, which NASA calls an indicator of cosmic ray activity, strongly recommend that the craft is moving outside the region of our sun’s influence.
“The protective influence of the sun is going to be less” as Voyager-1 nears the edge, stated York University’s Paul Delaney. And that will enable higher numbers of protons and electrons to hit the ship. “Anything you see above that (prior) rate has got to be an influence from outside the solar system.”
Ottawa astronomer Robert Fick mentioned the changing surroundings of Voyager-1 are probably significant, but they aren’t enough to prove that the craft has reached the edge of the solar system rather yet.
Suntzeff adds that the 35-year mission is unlike something we see in research today.
When NASA’s early Pioneer and Voyager probes had been launched in the 1970s, he stated, “it seemed natural to develop one thing that would take decades or even centuries to continue its journey. We saw hope in that.
“Jump forward to today exactly where tech-minded young individuals expect that two years of work can lead to a billion dollars if you are lucky, and corporation valuations depend on quarterly earning projections.
“Thinking so far into the future, such as building a satellite to ultimately probe the ISM (inter-stellar medium) or go to the nearest star is not something in our culture. We have lost a sense of wonder in the future.
That makes it so interesting is this… if there is indeed another planet/star on the edge of the solar system, sending comets to the Sun, then how can it maintain an orbit around the Sun if the Sun’s magnetic field ends before the Oort cloud?