January 2, 2026
Another year, another seven billion kilometres
We humans place a lot of importance on the time it takes for Earth to revolve around the sun. It takes one year, and we wind up in more or less the same place — relative to the sun — each time. A time for celebration!
But since the sun itself is orbiting around the centre of the galaxy, Earth moves along with it. With the sun moving at 220 kilometres per second, and Earth along for the ride, we end up seven billion kilometres away from where we were a year ago.
That seems like a lot, but in the vast emptiness of space, it’s hardly anything — just 0.0007 light-years per year. To put that into perspective, the nearest stars, in the Alpha Centauri system, are over four light-years away.
Which brings me to a pet peeve — why is so much science fiction based on conflict, even outright war, between beings from different parts of the galaxy? The time and expense would be unimaginable if it weren’t for the fertile imaginations of science fiction writers.
To get an idea of the vastness of space, think of the stars as specks of sand. If the sun was speck lying at your feet, you would have to travel to the other side of the world to find the closest other speck.
I just finished slogging through an epic novel where an entire “league” of planets orbiting various stars was at war with two sets of alien beings from other planets. What a colossal waste of resources.
I think the reason we can imagine it is because so many wars here on Earth have wasted millions of lives and billions of dollars. So why not scale up to the stars?