Space travel: “Voyager 1” hears a plasma hum

The signal is very weak and monotonous, “because it occurs in a narrow frequency band,” according to the astrophysicist’s report Stella’s hut Auker From Cornell University. She and her colleagues talk about the buzz of interstellar gas in one a studyWhich has just been published in Nature Astronomy.

Twin tentacles Voyager 1 The “Voyager 2” took off from Earth in the summer of 1977 and has lived their name (“The Traveler”) ever since. Voyager 1 flew over Jupiter in 1979, then Saturn a year later and left the solar system in August 2012. Since then, it has been flying in the interstellar space, the interstellar region.

“Like gentle and calm rain”

Since then, one of the tools has noticed the probe (Plasma wave system(The matter out there, the interstellar medium.) It is mainly hydrogen, and it is part of it in ionized form as plasma. Gauges have frequently shown disturbances in plasma waves, caused by an outbreak of activity in the sun. Between these outbreaks, there is clearly even a “plasma lull”.

“The interstellar medium is like a gentle or calm rain,” explains the astronomer and lead author of the study. James Awtar. Like lightning in a thunderstorm on Earth, Voyager 1 records the consequences of a solar storm, after which the gauges display the “gentle rain” of the signals again.

Stella Koch Ocker believes there are more of these rest phases in interstellar gas than previously thought. In the future, this could facilitate determining the local distribution of the plasma – regardless of what the sun does.