Matthew Gifford

My son observing the solar eclipse on August 21, 2017

Weekend notes: 10/25/17

Stellar observations

While I was trying to finish this post Sunday night, I couldn’t shake the feeling that writing this stuff is pointless. It doesn’t have any direct benefit on my life or career. Few people read it. Even fewer seem to find value in it.

Monday, while I was doing my lunchtime reading, I stumbled on a post that changed my mind. I’ll keep plugging away at this, trying to express whatever it is I need to express, trying to get better at it. I pulled this post out of the trash, cleaned it up, and put it out there for you. It’s not much. But I hope it’s worthy of your time.


Did you know that the world record for folding paper in half is 13 times? And if people could figure out how to fold it 103 times, it would be thicker than the width of the universe? Almost unbelievable.

Equally mind-boggling is the revolution that’s happening, I think largely unnoticed by non-nerds, in astrophysics. Since September 2015, scientists have detected gravitational waves caused by massive collisions in the universe on five separate occasions.

To really get how crazy this is, you have to understand the extremely large and small distances that this involves. Currently, there are three gravitational-wave-measuring instruments, called interferometers, in operation. Each L-shaped interferometer uses lasers traveling down vacuum tunnels to measure the slight movement of mirrors caused by passing gravitational waves. But these aren’t instruments sitting in a room. The arms of the two American instruments, called LIGO, are each 2 kilometers long. Each arm of the newer European instrument, called Virgo, is 3 kilometers.

By The Virgo collaboration (The Virgo collaboration) [CC0], via Wikimedia Commons

And what are these enormous observatories measuring? Distortions in space caused by huge collisions tens or hundreds of millions of light years away. Distortions that are less than a thousandth of the width of a proton.

It doesn’t even seem possible.

Why is this a such a big deal? First, it proves that the gravitational waves predicted by Einstein’s theory of general relativity exist. It also creates the possibility of a whole new era of astrophysics, where once-undetectable aspects of the universe are now visible to us.

It’s very exciting.


Did you know that the International Space Station is visible most nights regardless of your location? You just have to know when and where to look.


By Frankee 67 (Own work) [GFDL or CC BY-SA 3.0], via Wikimedia Commons

This is a great stellated dodecahedron. It’s pretty much my favorite polyhedron. Expect to see it somewhere on my arm in the future.


October 25, 2017

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