The point where the solar wind becomes slower than the speed of sound is called the termination shock ; the solar wind continues to slow as it passes through the heliosheath leading to a boundary called the heliopause , where the interstellar medium and solar wind pressures balance .
The point where the solar wind slows down is the termination shock ; the point where the interstellar medium and solar wind pressures balance is called the heliopause ; the point where the interstellar medium , traveling in the opposite direction , slows down as it collides with the heliosphere is the bow shock .