Why Astronauts left a reflector on the Moon! (ft. MinutePhysics) - Smarter Every Day 73 | Summary and Q&A

TL;DR

Astronauts left retro-reflectors on the moon to conduct experiments, allowing scientists to measure the distance to the moon and test principles of general relativity.

Key Insights

• 👾 Retro-reflectors left on the moon by Apollo astronauts continue to provide valuable data for scientific experiments.
• 🙂 Corner reflectors use the reflection of mirrors to manipulate light and enhance accuracy in measurements.
• 👾 Retro-reflectors are not limited to optics and have applications in radar systems.
• 🥮 The distance to the moon can be calculated by measuring the time it takes for light to travel to the moon and back.
• 👾 Retro-reflectors play a significant role in the study of the moon's rotation, orbit, and tectonic plate movement on Earth.
• 👻 They also allow scientists to test fundamental principles of physics, such as general relativity.
• 💥 Corner reflectors on Earth are used for radar navigation, preventing collisions by reflecting radar signals.

Transcript

Hey it's me Destin. Welcome back to Smarter Every Day. So did you know that in the 60s and 70s when the astronauts went to the moon in the Saturn 5 rocket, they actually left experiments on the surface of the moon? In fact there's one that's still there today and it's still operating. We're still getting data out of it. But before I explain that, I... Read More

Questions & Answers

Q: How do retro-reflectors on the moon allow scientists to measure the distance to the moon?

By timing how long it takes for light to travel to the moon and back, scientists can calculate the distance within centimeters.

Q: What other experiments are conducted using retro-reflectors on the moon?

Retro-reflectors are used to understand the moon's rotation and orbit, monitor tectonic plate movement on Earth, and test principles of general relativity.

Q: How are corner reflectors used in radar systems?

Corner reflectors made of metal are used as passive lighthouses to guide radar systems by reflecting the radar signal, allowing for safe navigation under bridges.

Q: Did the Apollo astronauts leave their waste on the moon?

It is likely that the astronauts left their waste on the moon, as there would be no need to bring it back to Earth.

Summary & Key Takeaways

• NASA left retro-reflectors on the moon's surface, which still provide valuable data to scientists today.

• Corner reflectors use multiple mirrors to reflect light back to its source, allowing for accurate measurements and observations.

• Retro-reflectors have applications beyond optics, such as radar systems used to navigate under bridges.