Somewhere beyond the edge of our solar system, nearly 14 billion kilometers from Earth, a NASA space probe heard an unexpected and persistent hum. And this buzz is now helping researchers understand the matter of the deep cosmos.
The space probe that made the discovery is an ancient, Voyager 1. It took off into space in 1977 and is now the most traveled man-made space object ever. It is therefore currently located nearly 23 billion kilometers from Earth. More than 150 times the distance of our planet from the sun. His mission was to study the planets in our solar system on the way out, but in 2012 he flew out of that solar system and since then has flown deep into the cosmos and – miraculously – still contributes to research.
The latter measure was taken from data by scientists at Cornell University in the United States. Previously, something was sometimes measured so far away, but it was possible thanks to the sun’s flares. These deliver a shock wave through space, which Voyager could absorb. This meant that something could already be said about the density of space. Now they have found a constant vibration, going back to 2017, and they could see that the density is varying.
So that tells us something about the matter that the solar system actually goes through. Not everyone will consider this, but our solar system is moving through space at about 720,000 kilometers per hour. What exactly is he going through? And is the density of this material about the same or is it variable? And is it everywhere or only in certain regions?
The chances of a space probe being able to take measurements this far are low. It takes a long time to get there. Voyager took off in 1977 and left the solar system in 2012. Then it flew for another 9 years. So I hope it will last a while and thanks to this elder we will soon learn more about the vibrations and variations in the deep cosmos.
In this audio you can hear astronomer Floris van der Tak (RUG and SRON). Find out more here: As NASA’s Voyager 1 studies interstellar space, its density measurements are making waves.