The edge of our solar system is a region called the heliopause. The heliopause is the boundary where the solar wind, a stream of charged particles emanating from the Sun, slows down and merges with the interstellar medium, the gas and dust between stars. It marks the transition from the influence of the Sun to the influence of the broader interstellar space.
Determining the location of the heliopause and studying what lies beyond it is a scientific endeavor that involves data analysis from various spacecraft and instruments. Currently, the Voyager 1 and Voyager 2 spacecraft, launched in 1977, are the farthest human-made objects from Earth and have provided valuable information about the heliopause and the interstellar space.
Voyager 1 crossed the heliopause in 2012, becoming the first human-made spacecraft to enter interstellar space. Voyager 2 followed suit in 2018. These spacecraft continue to operate and send back data about the conditions they encounter as they travel through interstellar space.
By analyzing the data received from the Voyager spacecraft, scientists can gather information about the density, temperature, and magnetic field of the interstellar medium. They study changes in the particles and radiation surrounding the spacecraft to understand the characteristics of the heliopause and its boundary.
In addition to the Voyager spacecraft, other missions and instruments, such as the Interstellar Boundary Explorer (IBEX) and the upcoming European Space Agency's Solar Orbiter, contribute to our understanding of the heliopause and the region beyond it.
While we have gained insights into the heliopause and interstellar space, our knowledge is still limited. Continued research and the development of new missions and technologies will help us expand our understanding of the edge of our solar system and the vast expanse of interstellar space.