> Prior research has shown that, at the edges of the solar system, there is a point at which the solar wind slows to a speed at which sound can travel—it is called the termination shock. Prior research has also shown that there exists a point where the solar wind becomes incapable of pushing back against pressure exerted by interstellar space—it is called the heliopause. Both of the Voyager space probes have pushed through this boundary and into interstellar space. And as they did so, they sent back sensor data.

> By analyzing data from three sources, the researchers noted a sudden change in pressure exerted by the solar wind in 2014, and used the relatively short time scale of the event to study the shape of the heliopause and termination shock. When modeled, the researchers found that huge ripples were formed in the boundary areas. They also found major shifts in the distance to the heliopause, suggesting that its shape was not uniform and that it was continually changing for unknown reasons.

> The researchers hope to learn more about the boundary of the solar system using data sent back to Earth from a new probe set to launch in 2025—it will be capable of sending back measurements of neutral atom emissions with higher precision.