Good question - How fast are you moving through the universe right now?

Marshall Brain

Chances are that you are sitting in a chair right now, so it seems like you are stationary. But in fact you are moving through the universe at a tremendous speed at this very moment. Let's take a look at where all that motion is coming from.

The first thing to consider is the earth's rotation. The earth is 24,900 miles in circumference at the equator, or 40,000 kilometers. The earth takes 24 hours to make one rotation. So:

24,900 / 24 = 1,037 MPH or 1,666 KPH

As you move toward the poles that number decreases. At the north pole the speed is zero and you are simply rotating in place at one rotation every 24 hours. So let's assume you are sitting somewhere in South Florida moving at about 1,000 miles per hour or 1,610 KPH.

The Earth is also making one orbit around the sun every year. That sounds like a long time, but the orbit is huge. The Earth is roughly 93 million miles (150 million km) away from the sun, giving its orbit a circumference of 584 million miles (942 million km). That works out to 66,666 MPH or 107,000 KPH.

If you are on the side of the planet where the planet's rotation is moving in the same direction as the orbital direction, these two speeds add together. If you are on the opposite side, they subtract. We are trying to calculate a maximum speed, so we will be adding.

Our solar system itself is also moving in an orbit around the galactic core. The solar system is something like 25,000 light years away from the center of the galaxy, and the galaxy makes one rotation every 250 million years or so. That gives the solar system a speed of something like 420,000 MPH or 675,000 KPH.

And then the galaxy itself is moving. According to this page:

the Milky Way and Andromeda galaxy are approaching each other with a speed of about 130 km/s, however the collision of these two galaxies will not occur for about 5 billion years (AstroFile). Another result I found was that our galaxy and neighbors are moving at 600 km/s in the direction of the constellation Hydra (Scientific American). Finally, I found that the Milky Way moves through space within the cluster of galaxies it is a member of, and this cluster in turn moves through space towards yet another larger cluster of galaxies off in the direction of the constellation Virgo. This speed is approximately 300 km/s (Ask the Space Scientist).

So there is speculation that the galaxy is moving through the universe at a speed of 1,000 km/s, which means 3,600,000 KPH or 2,237,000 MPH.

Adding it all up, you get:

1000 + 66,666 + 420,000 + 2,237,000 = 2,724,666 MPH


1,610 + 107,000 + 675,000 + 3,600,000 = 4,383,610 KPH

In other words, you are hurling through space at 2.7 million MPH (4.4 million KPH) even though it feels like you are sitting still.

More info: These links may also help: - What does it mean when they say the universe is expanding? - The scale of our universe - Good question - How big are the cells in your body? - Good question - how big is the universe? - If there are millions of stars in the universe, why is it so dark? - How the Drake Equation Works - calculating the number of advanced civilizations in our galaxy - how big is the universe? - How to get home if you are lost in the universe - Where did our universe come from? - Does the universe expand forever, or contract and expand in an infinite series of big bangs? - How the James Webb Space Telescope Will Work - the most important number in the universe - How the Multiverse Works - How Gamma Ray Bursts Work - the biggest explosions in the universe - How Can We See Galaxies 47 Billion Light Years Away When the Universe is Only 13 Billion Years Old? - What is the universe expanding into? - How did the universe begin? - How the universe works - 96% of the universe is missing - A tour of the universe courtesy of the Hubble telescope

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