The shape of Earth

OK, hold on because I’m telling you two big secrets:

1. Earth is not flat. It’s like a ball slightly squashed from the top. Technically its shape can be approximated as an oblate spheroid, but we can consider it a sphere.
2. It is not hollow either. Jules Verne’s Journey to the Center of the Earth is a work of invention, there is no prehistoric world waiting for us deep inside Earth.

Curiosity pills: distances in the Solar System.

If you imagine to shrink the Earth to the size of a golf ball (4.3 centimeters diameter), and the rest of sizes and…

A matter of generations

My son was born in 2013. I was born in 1978. My dad was born in 1947 and my grandfather in 1912. My father’s grandma — my great grandmother — was born in 1893 (I did not know my great grandfather, he went to America when my great grand mother was pregnant with my grandmother, became a lumberjack in California, fell in love with a nurse, and never came back. OK, this is another story).

110 years and 5 generations passed between my great grandmother’s and my son’s birth. It may seem a long time: in 1893 Italy was still…

Everyone who writes on Medium is concerned by his own views statistics, but compulsively looking at them will not change their numbers.

Here is the story of my obsession

The story so far

I discovered Medium a couple of years ago. It was a rich source of useful information for my articles and stories, and I begun reading something on it almost everyday. Soon afterwards I jumped over the bar and started writing my contents too.

I wrote a few articles about my thoughts about the books I read, and made them freely available, sharing them on my Facebook profile; they are written in…

Coronavirus. Everybody is talking about it, everybody is familiar with words like pandemic, social distancing, etc.

But what is a virus? how small is it? Lets’ figure out.

Starting from the cell

The human body — and also the bodies of the other living beings — are made of cells. A huge amount of cells.

Scientists estimated an average human body is made of around 3x10¹³,
30 trillions, that is: 30 000 000 000 000
By the way, this means there are more cells in your body than stars in the Milky Way.

Cell are the basic building blocks of living things and in…

Avogadro’s number did not come from Avogadro

In 1811, the Italian chemist and physicist Amedeo Avogadro stated his famous law:

Equal volumes of gas, in the same temperature and pressure conditions, contain the same number of molecules.

But how many molecules?

The short answer is: a lot.

The long answer is: well, quite a lot.

Open your high school astronomy textbook: probably there is a picture of the Solar System showing the planets aligned and close together like the beads in a string (Pluto we miss you!).

That is for sure a nice picture, useful for showing all the planets, but a misleading one too. Planets are very, very, very far apart one to each other, and the Solar System is essentially, well, empty space.

One thing difficult to grasp when thinking of the Universe is how HUGE it is, and also in our Solar System, nothing more than our backyard, astronomically speaking, distances are…

— Strana la valigia che hai.
— Tappeto.
— Serve a portarci i tappeti?
— È fatta con un tappeto.

(Mary Poppins)

Ho sentito parlare di Luca Quarin per la prima volta circa un anno fa, a una presentazione del suo libro, Il Battito Oscuro del Mondo. Ci ero andato più perché invitato da degli amici che per reale interesse, ma rimasi subito colpito dal modo di parlare di Luca, dal suo spaziare attraverso argomenti diversi, da tutto quello che sapeva e che voleva raccontare, dalla maniera in cui lo faceva. Comprai il libro, incuriosito, e andai a cena con…