What is Interstellar Space?

10 Cool Facts About Interstellar Space

1. Voyager 1 was the first human-made object to leave our solar system. This spacecraft entered interstellar space in 2012, and Voyager 2 followed in 2018.

2. Interstellar space isn’t totally empty. Even though it looks like nothing is there, it actually contains tiny particles of gas, dust, and radiation spread out over vast distances.

3. It’s unbelievably cold. The temperature in interstellar space is about -455°F (-270°C)—only a few degrees above absolute zero, the coldest temperature possible.

4. New stars are born in interstellar space. Clouds of gas and dust slowly come together over millions of years, eventually forming new stars and planets.

5. There’s a lot of radiation out there. Without the Sun’s protection, interstellar space has dangerous high-energy particles called cosmic rays, which could be harmful to astronauts.

6. Mysterious space objects sometimes pass through our solar system. ‘Oumuamua, a strange rock-like object from another star system, flew past Earth in 2017.

7. Spacecraft signals take a long time to reach Earth. Messages from Voyager 1 take over 22 hours to reach us, even though they travel at the speed of light.

8. The Sun is moving through interstellar space. Our entire solar system is flying through the galaxy at about 500,000 miles per hour, creating a sort of shockwave in space.

9. Interstellar dust might have helped create life. Tiny particles in space contain complex molecules, including some that might have helped form life on Earth billions of years ago.

10. We’ve barely explored interstellar space. The Milky Way galaxy is 100,000 light-years wide, and we’ve only just begun to explore beyond our tiny solar system.