The great thing about a brand new year is that if you didn’t like how the old one went, you can start all over and make this one better.
At least when you’re talking about Earth years, though there’s also something called the galactic year, and that one just keeps going and going and going.
We all know that a year marks the length of time it takes our planet to make it all the way around the Sun, during which the Earth revolves on its axis a little over 365 times.
But while the Earth does all that rotating and revolving, the Sun is moving too, at something like 500,000 miles an hour.
And it’s orbiting the black hole at the center of our galaxy, the Milky Way.
When it makes it all the way around that orbit, it’s called a galactic year.
And while moving a half a million miles an hour in space is pretty fast, the orbit is really, really big.
So the Sun’s galactic year lasts between 220 and 230 million Earth years.
That’s such a long time that the Sun isn’t even 21 galactic years old yet, and the universe itself is only maybe 60.
All of human history, everything we’ve ever done, has happened in just one of the Sun’s trip around that black hole.
It’s a scale that’s hard to even wrap our heads around, even if we could stick around long enough to see one of these orbits end and another begin.
But that doesn’t mean we can’t celebrate!
Back in 2016 a group of astronomers suggested a a way to mark the Sun’s movement around the galaxy by ticking off one section of the trip about every 1.74 Earth years.
They call it Galactic Tick Day.
Today in 1959 – or some say 1958 – Johnny Cash played a concert for the inmates at San Quentin Prison.
In the crowd was a young prisoner named Merle Haggard, who said seeing the Man In Black in person inspired him to turn his life around and pursue a career in music.
And if you know even a little bit about country music, you know what he went on to do after he got out.
How long is a galactic year? (Live Science)
On This Day: Johnny Cash Performed for an Imprisoned Merle Haggard at San Quentin (American Songwriter)
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Photo: NASA/JPL-Caltech
