How fast is the ISS?

We’ve done International Space Station posts before. Many of them.
There are even photos.

But it’s been a while and so I have grasped the opportunity presented to me by xkcd.com to answer the question: How fast is 8km/s anyway?

8km/s is the speed that the ISS goes – indeed, has to go – in order to continue orbiting the earth. However, because of the unfamiliar units, people find it difficult to visualise exactly how quick it is, especially when shown the serene footage of earth taken by Chris Hadfield and others.

8km/s is equal to 28,800kph or just under 18,000mph. Yes. Go whoosh whoosh.

It’s 10 times faster than a rifle bullet.
Travelling at 8km/s, you could get from Cape Town to Joburg in 2 minutes and 38 seconds. If you wanted to.
Or Cape Town to London in 20 minutes. Pop over for a pint of real beer and some annoying accents.

But the best way of visualising it comes from the what-if crew, with the help of the Proclaimers:

To get a better sense of the pace at which you’re traveling, let’s use the beat of a song to mark the passage of time. Suppose you started playing the 1988 song by The Proclaimers, I’m Gonna Be (500 Miles). That song is about 131.9 beats per minute, so imagine that with every beat of the song, you move forward more than three kilometres.

It would take you about two lines of the chorus to cross the English Channel between London and Paris.

The song’s length leads to an odd coincidence. The interval between the start and the end of I’m Gonna Be is 3 minutes and 30 seconds, and the ISS is moving is 7.66 km/s.
This means that if an astronaut on the ISS listens to I’m Gonna Be, in the time between the first beat of the song and the final lines, they will have traveled just about exactly 1,000 miles.

And that being the case, they’d have every excuse to fall down at my door.

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