One Is the Loneliest Number

Or Is It?

I had to do a bit of a long drive today and while I was tootling along in the car, I heard the old Three Dog Night song written by Harry Nilsson called “One is the Loneliest Number”. And as is my usual case, that set me to thinking about all kinds of things, including…  the number 1.

Mathematically, 1 is an interesting entity.  First, it stands for a single thing.  Sometimes we refer to it as “unity”.  It’s the first non-zero whole number, and if you multiply any other number by 1, you get that number.  You get an “identity”.  So 1 x 1 = 1, 1 x 50 = 50, and so on. It’s an odd number, meaning it can’t be divided evenly by 2. There’s lots to know mathematically about 1, which you can read here.

1 (one) gets a lot of play in cultural references — like in the song I mentioned above.  Who hasn’t heard of Neo being “the one” (in The Matrix), or calling someone your “one and only” in a romantic setting?

In binary code, 1 is one of two pieces in a base-2 system of counting (the other being zero).  The binary system is used by all computers, which is where you often see the term “ones and zeros”.

This image of the spiral galaxy NGC 2841 began as data--a series of ones and zeros transmitted back to Earth from Hubble Space Telescope. Courtesy STScI.

In astronomy these days, all the digital imagery and data you see streaming from various instruments is in the form of “ones and zeros” which get encoded into the pictures and graphs we see.  Astronomers use fairly complex computer programs to decode the images, apply algorithms to remove errors and data dropouts, and colorize, sharpen, mask, or other imaging processes to help them understand what they see in their images and data.

Astronomy brings me to an interesting element: hydrogen. Yes, it’s also part of what we study in chemistry when we learn the elements. In fact, hydrogen is the chemical element with the atomic number 1. But, when you start to study the universe in astronomy, you very quickly run into hydrogen, which means you quickly learn about it as a chemical element.

The most abundant isotope of hydrogen (think of “isotope” as “form”) has one proton in its nucleus and no neutrons.  Hydrogen, element number 1, is the most abundant chemical element in the universe. An astounding 75 percent of the normal matter in the universe (not including dark matter) is hydrogen, and 90 percent of the atoms in the universe are hydrogen. When you look at stars, or nebulae, or the planet Jupiter for that matter, you’re seeing LOTS of hydrogen.  In clouds of interstellar gas and dust where stars are born, for example, the hydrogen is in the form of a gas — H_2. It’s in what’s known as the “molecular state”, where atoms of hydrogen bond to form molecules of the gas. Hydrogen also exists as free atoms, and also in an energized (think: heated) and magnetized state called a plasma.

Molecular structures of the 21 proteinogenic amino acids (click to enlarge). Courtesy Dan Cojocari under a Creative Commons Atribution-Share Alike 3.0 license.

As befits an element whose number is 1, hydrogen was the first element created in the Big Bang. Within moments of that creation, heavier isotopes of hydrogen came about (like deuterium) and then forms of helium and lithium. But hydrogen was number 1 in the beginning.  And, judging by its abundance throughout the cosmos, it’s still number 1. It’s what you need to form stars (from those gas clouds), it is an essential component of many chemical compounds like water (H₂O), or amino acids (see the image to the right).

YOU are largely made of water, and thus your body has a great deal of Element Number 1 in it. All life on this planet dabbles in water, evolved in water, and uses water to survive. There are billions and billions of life forms on Earth, and they all depend in some way on water, which is mostly hydrogen.

That hydrogen link gives us a common bond with the rest of the cosmos — the single atomic and elemental link that stretches back across more than 13.7 billion years to when the first atomic particles of hydrogen came into being and began the dance of cosmic evolution.

So, in a sense, while 1 may be the loneliest number, because of hydrogen, we are all one with the universe in a very elemental and scientific way.