# What Really Happens in a Second

As the 25th leap second approaches (If you haven’t heard the news), there’s been a myriad of tweets and Facebook statuses joking about how to spend that extra moment when the clocks hit 11:59:60 UT. What many people don’t realize though is that a lot can happen in a second.

Let’s start with the basics. The SI definition of a second is 9,192,631,770 periods of the radiation produced by a particular transition in a cesium-133 atom. In the same second, this radiation (or any other form of light in a vacuum) would travel 299,792,458 meters, or approximately 7 times around the earth.

Speaking of light, our sun consumes around 500 billion kilograms of hydrogen every second to produce around 10^27 joules of energy. Although we receive only about a billionth of the total energy (10^18 joules), it’s still enough energy to power all of humanity for a year.

The amazing rate of natural events isn’t only in outer space. The earth experiences over 100 lightning strikes every second, amounting to more than 8.5 million strikes every day. The Amazon river discharges 175,000 cubic meters of water per second into the Atlantic, enough to fill seventy 10-lane Olympic swimming pools.

Finally, let’s not forget human accomplishments. I could not have written this post without help from Google, which is performing over 30000 searches every second. Sequoia, the IBM BlueGene supercomputer at Lawrence Livemore National Lab, can perform over 16 quadrillion operations (that’s 1.6 * 10^15!). However, even with these super computers, we can only simulate simple biological systems (ie: basic protein folding) for a few microseconds, much smaller than the actual time scale of cellular events. Each of the tens of trillions of cells in our body, for example, have proteins capable of replicating 50 nucleotides of DNA every second.

The things cited here barely scratch the surface of all the events happening every second of every day. It’s truly wonderful to appreciate everything that is going on around us without our knowing. I hope you enjoy the extra second and have a little new perspective whenever someone says “Seize the moment”.

****A word of caution to readers: Most of the values in this article, other than the exact definitions like the second or the speed of light, are meant to be order of magnitude approximations. You are likely to find different values if you use different sources.

### One Comment

1. Schrödinger says:

Not to mention things happening outside our solar system. Like the number of stars that are born per day : around 400 million. That means 4800 star births per second! :O