Is all of our universe… lit? Can you be hurtling through space and accidentally fly head first into a planet because oops you didn’t have your headlights on?
In: Physics
Really good question because it requires multiple answers.
1) There’s a **LOT** of space in space. So it’s not likely to hit something except over really long periods of time (Billions of years).
[Astrophysicist Dr. Becky – Likelihood of Stars to Collide](https://youtu.be/_dZUNAZI2eg)
2) There is actually a lot of rogue planets, asteroids, dust, and other materials out there that are very dark and so would be hard to detect with our current technology until you crash into them.
[PBS Spacetime Dark Matter](https://youtu.be/z3rgl-_a5C0)
3) Technically, the vacuum of space is most likely the coldest thing in the universe at a chilly 2.73 K. So any real object made of atoms is warmer than that and so glows some light. This light can be infrared light that you might be familiar with from those glowing red heaters. You and I can’t see that light, but your skin can feel it as warmth and we have scientific sensors that can see it.
[Scishow Space Coolest Place in Outer Space](https://youtu.be/E5VTmc-QM6Q)
[PBS Spacetime Cosmic Microwave Background](https://youtu.be/3tCMd1ytvWg)
4) If you had a really bright headlight in front of your spacecraft, even if you were moving really fast up to high percentages of the speed of light (like 99%). The light you emit would still head away from you at the speed of light and so would illuminate objects ahead of you. Though you may not be able to correct your course in time to stop the crash.
[VSauce Would headlights work at the speed of light?](https://youtu.be/ACUuFg9Y9dY)
[PBS Spacetime Speed of Light](https://youtu.be/msVuCEs8Ydo)
Edit: Added video links
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