## A Piece of Paper as Thick as the Universe

###### By Anupum Pant

Linear growth is only what we can visualize well. Estimating things that grow exponentially, is something not many of us can do properly.

Here’s what happens when you fold a piece of paper. A paper of thickness 1/10 of a millimetre doubles its thickness. On the second fold it is 4 times the initial thickness and so on. It doesn’t really seem like it would grow a lot after, say, 10 folds, right?

After 10 folds, the paper which was about the thickness of your hair, turns into something that is as thick as your hand.

Without any calculation, how thick do you think would it become if you could fold it 103 times?  (I know, no one has ever folded a paper more than 12 times)

Think about this for a second: How many times do you think would you have to fold a paper to make it 1 kilometre thick? The answer is 23. Yes, it takes just 13 more folds to go from the thickness of a hand to a whole kilometre.

Turns out, if you manage to somehow fold a paper 30 times, it would become 100 km tall. The paper would now reach the space.

For the sake of imagining how exponential growth works, a paper folded 103 times would be about 93 Billion light years thick – which is also the estimated size of the observable universe.

Watch the video below to see one other great example of how exponential growth can mess with you.

## World’s Largest Building Has a Climate of Its Own

###### By Anupum Pant

A place where planes like the Boeing 747, 767, 777 and 787 are built, has to be huge. But this Boeing factory in Everett, Washington, home to 30,000 workers (working in 3 shifts), is so huge that the inside of the building has a climate of its own. It is the largest building on Earth. If you get a chance, you must not drop a chance to take the 90-minute tour of this factory (it costs \$15 per adult). Here are a few things to note about it…

The size: The volume of this factory is 472 million cubic feet or 13.3 million cubic meters. That is enough to fit the whole Disney land and still be left with a 12 acre place to park the vehicles. In other words, it could fit 800 standard sized hockey rinks. Or it could fit in 75 football fields. Or it can hold about 12 empire state buildings! You get an idea how huge it is, right?

Largest Digital Mural: Being huge comes with its own side effects – another world record. The doors, like the building, are huge too. The factory has 6 doors, where each of them is 82 feet in height and 300-350 feet in width! You could bring in an NFL field (as in, fit the length of it) in through one of these. But what is more interesting about these doors is that they are covered with a 100,000 square feet of digital graphic. This is the largest digital mural in the world – printed by SuperGraphics, Seattle. It took the workers 27 days to install the digital mural.

Small City: Had this place been slightly larger, it could have had enough space to fit in a country – The Vatican city. Still, it isn’t small. The building is like a small city with it’s own fire department, security force, fully equipped medical clinic, electrical substations and water treatment plant. To move around in this little city, the employees use 1,300 bicycles.

Its own Climate? Now, since it is like a small city, it has to have its own climate, right? Yes. When the building was first built, clouds got formed inside and some say it even rained inside (mostly, not true). But rainbows have definitely been seen inside.
The temperature inside the building is controlled by those 1 million bulbs that are used in there. During winters, the bulbs bring warmth and during summers the doors are opened and air circulating fans are switched on to let the fresh Everett breeze come in.

Bonus fact: The network of 26 overhead cranes have about a total of 39 miles of ceiling rails inside the factory!

## A Natural Explosion That Knocked 80 Million Trees

###### By Anupum Pant

In the year 1908 (June 30), a remote part of Siberia experienced something really mysterious and really huge. It was an explosion that took place at about 5-10 km altitude in the air which was estimated to be as powerful as 1000 (or 185 according to NASA) Hiroshima bombs!

No one could ever figure out what really caused it. However, scientists were pretty sure that it was either a huge meteorite of about 100 feet (some say 1000 m) in diameter which crashed into the earth’s atmosphere and disintegrated, or it just bounced off the earth’s atmosphere like a huge skipping stone. Besides the scientific theories, there are a number of other “UFO and alien” stories that have been associated with this event. This was called the Tunguska event.

The sheer size: The explosion was utterly gigantic. So big, that it is still considered to be the most powerful natural explosion in the known history. The shock-waves from the explosion knocked people off their feet, and these people were 40 miles away from where the explosion happened. It wasn’t just people, 80 million trees over an area of 2,150 square kilometres were knocked down in a radial pattern (with trunks pointing away from the epicentre). 80 million! Wow!

It caused a mini earthquake and a NatGeo article says that the lake Checko could have been created due to this impact.

Eyewitness’ account:

Suddenly in the north sky… the sky was split in two, and high above the forest the whole northern part of the sky appeared covered with fire… At that moment there was a bang in the sky and a mighty crash… The crash was followed by a noise like stones falling from the sky, or of guns firing. The earth trembled.
[NASA website]

Had this taken place above a metro city, the city would have been completely levelled by the event. But that is highly unlikely because cities take up a very small fraction of area on the earth’s surface. Moreover, very rarely do such events happen.

What is very likely is that such an event could happen over the part which covers 70% of the earth’s surface – the ocean. Such an event could create a huge Tsunami causing a lot of destruction on land.