This Is A Light-Nanosecond!

less than 1m read

·Nov 10, 2024

I trimmed my beard yesterday, so I'm feeling a bit like a baby today. But look at the trimmings! Specifically this one that is 2.4 fortnits worth of beard growth. How do I know? Well, because of this tool I made. This about 5 years ago to free people from the tyranny of standard units. It measures in weird units like beard fortnits, the typical length of beard grows every 2 weeks.

It's also got light pico seconds, how far light travels in a trillionth of a second. If you didn't get one 5 years ago but you're subscribed much later this year, three boxes from now you'll get one in a special Legacy box we're making. The entire ruler is exactly one light nond long. This is how far light travels in a vacuum in 1 nond.

Everything I see from this distance, I'm seeing as it was a billionth of a second ago. It's a reminder that you live in the past because light has a finite speed. You do not see things as they are; you see the universe only as it was. Also, you're going nowhere if you fall asleep tonight in the same bed you woke up in this morning. Your average velocity for the day will be zero.

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