Today in History: September 12, Voyager 1 Leaves the Solar System

Introduction

On September 12, 1990, Voyager 1 became the first spacecraft to leave our solar system and enter interstellar space. Launched in 1977, Voyager 1 was part of a pair of NASA probes sent to explore the outer planets. Both spacecraft journeyed through the asteroid belt and past Jupiter, Saturn, Uranus, and Neptune, capturing stunning images and providing valuable data. But Voyager 1 went further, its trajectory leading it beyond the influence of the Sun and into the vast expanse of interstellar space.

Exiting the Solar System

Voyager 1's journey out of the solar system was a gradual one. As it traveled farther from the Sun, the Sun's gravitational pull weakened, allowing the spacecraft to accelerate. The spacecraft's instruments detected changes in the intensity and direction of the Sun's magnetic field, providing evidence that it was moving into a new region of space.

Finally, in August 2012, Voyager 1 crossed the heliopause, the boundary between the solar wind and the interstellar medium. The spacecraft had officially left the solar system and entered interstellar space.

Exploration of Interstellar Space

Since entering interstellar space, Voyager 1 has continued to send back valuable data about the environment beyond our solar system. The spacecraft's instruments have detected cosmic rays, energetic particles that originate from outside the solar system. Voyager 1 has also measured the density and temperature of the interstellar medium, providing insights into the composition and evolution of our galaxy.

Voyager 1's mission is expected to continue until 2025, when its power supply is projected to run out. By then, the spacecraft will be over 11 billion miles from Earth, providing us with a unique vantage point from which to study the universe.

Conclusion

The Voyager 1 mission is a testament to the human spirit of exploration. The spacecraft's journey beyond the solar system has provided us with invaluable insights into our place in the universe and whetted our appetite for exploring the vastness of space. As Voyager 1 continues its voyage through interstellar space, it serves as a reminder of the boundless possibilities that lie beyond our reach.