Tag Archives: space

Einstein’s Special Theory of Relativity


As you move faster, time slows down for you. Even though that’s true when you’re riding in a car, the slowdown is so teeny-tiny that it’s not worth measuring. But, if you were to travel to another galaxy at almost the speed of light, time would slow down—for you—to the point where you would age more slowly than your pals back on Earth.

When you got back from your trip, your friends would be old and wrinkly but you’d be ready to graduate from high school.

Back to the beginning of The Western Civ User’s Guide to Time & Space

Man-made moons

Okay, remember back when we talked about how Galileo thought that we could use the moons of Jupiter as a clock, and their location would help us find our location on Earth? Or how about when Nevil Maskelyne figured we could use the positions of the stars and planets to find out where we are—if we know what time it is?

Maskelyne put in a ton of night-time hours charting the courses of the stars and planets. How much easier it would have been if the heavenly bodies just told him where they are. Well, guess what? Right now, as you sit there eating your frooty kibble, there are over 19,000 moons—man-made satellites—orbiting the Earth that we shot up into space. Every last one of ‘em sends back a constant signal telling us where exactly it is, and the time.

satellite

https://www.space.com/24839-satellites.html
https://www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-a-satellite-58.html
https://www.noaa.gov/satellites
This site shows you where every satellite is right now—https://maps.esri.com/rc/sat2/index.html
Quickie overview of satellites for kids with a charming young lady and a puppet constructed 10 minutes before showtime—https://www.youtube.com/watch?v=03pZdYVacaM

Postcards!

postcard.shot

I got postcards! They have my weird hand-lettering and a lovely astrolabe on the front. The back tells how to find The Western Civ User’s Guide on the internet. I’ll be sending these out to promote my blog and this history I’m writing. The plan is to eventually turn it into a printed book.

If you’d like me to send you a postcard, shoot me an email at john@johnmanders.com.

I do appreciate you guys who read my posts. Thanks for spreading the word.

By the way, these were printed at Best Printing in Oil City, Pennsylvania. Nice job, Licia!

Back to the beginning of The Western Civ User’s Guide to Time & Space

Time & space

Yes, yes, I know—my phone has been ringing off the hook with people calling to complain that this history of Western Civilization seems to be a history of telling time. Maybe you have a point. Maybe I have been concentrating too much on how the ancients reckoned time.

This history is about ideas. I want to tell how Western Civilization was shaped by innovation and invention. Look, would it make you all happier if I added a second topic? I admit, so far (even though we’ve only gotten as far as the Sumerians and Egyptians) I *have* been a little obsessed with timekeeping. How about if I start talking about how we’ve measured space?

What if we discovered that there’s a connection between time and space?

For instance: how far can you walk in an hour? If you keep up a steady pace, you’ll cover 3 miles. A long time ago, this unit of measurement was called a league. Most people traveled by walking. They knew that in an hour they could be somewhere 3 miles away. They were using time to measure distance.