The vast, dark region, where no object from the world had ever entered before, was touched for the very first time by Voyager 1 in August 2012. The NASA spacecraft has been zooming faraway from our planet since its launch in September 1977, and even after four decades since its launch, it continues to form remarkable discoveries and send data back home from billions of kilometers away!
Throughout its journey, the Voyager has revealed many secrets of the vast universe. And now, adding another feather to its hat, the guided missile has detected a faint plasma hum within the region.
In a politician statement released by Cornell University, Stella Koch Ocker, one among the authors of the study, explains: “It’s very faint and monotone, because it’s within the narrow frequency bandwidth. We’re detecting the faint, persistent hum of interstellar gas.”
‘Hum’ within the vast empty space
This breakthrough discovery was made by the Plasma Wave System instrument onboard the probe, which is employed to live the electron density. Surprisingly, the space probe’s instruments are still functioning to slowly relay back data from quite 14 billion miles away.
The spacecraft heard such interstellar sound for the primary time just three months after exiting the heliosphere and entering the dark region , while the second sound or ‘whistle’ was recorded six months later. The latter was found to be louder, with a better pitch as compared to the previous sound. From this, the team suspected that the interstellar space could also be getting thicker at a faster rate.
As per NASA, the interstellar space consists of turbulent waves which might be originating from several sources, just like the rotation of our galaxy.
“As these waves reverberate through space, they vibrate the electrons around them, which ring out at characteristic frequencies counting on how crammed together they’re. The upper the pitch of that ringing, the upper the electron density,” a NASA statement explains.
This produces the ‘hum’ which scientists have named as a plasma wave emission. The team studying the info derived from Voyager 1 has heard several such sounds at irregular intervals since the spacecraft’s entry into region.
Through this discovery, scientists will now be ready to conduct the very first measurements of the density of fabric in region, which can effectively open a replacement pathway for the exploration of the structure of the very nearby interstellar space .
The results of this study could also prove crucial in helping us expand our understanding about the form of the heliosphere, how stars form, how the interstellar space interacts with the solar radiation, and even our own location within the galaxy.
The unique Voyager 1 mission was launched by NASA to review the outer system , and planets like Jupiter and Saturn on its way. The spacecraft’s 44-year-long journey has been considered a serious milestone in space exploration.