Astronomy is about BIG things!

By Tom Kando

Nowadays, cosmology and quantum physics are moving into unfathomably mysterious directions.

The Higgs Boson, which is supposed to be the means by which things in the universe obtain mass, is said to maybe have been observed for the first time recently - at CERN’s large Hadron Collider in Geneva. And scientists there, together with the “OPERA” team in Italy, are said to have detected faster-than-light (muon) neutrinos - maybe.


Of course, quantum theory has long said things which are difficult to comprehend for the lay person. There is Heisenberg’s uncertainty principle, Schrodinger’s “cat” thought experiment, which describes a paradox whereby a cat in a box is both dead AND alive, as long as it remains unobserved. Nowadays, people speak of parallel universes and multiverses, of which ours is only one. One hears statements such as “if anything CAN happen, it DOES” (in some universe or another, presumably).

I don’t know anything about such things. But I have always found the universe fascinating - the one universe which we know, the one in which we live. Its sheer size always astounds me. Here are some facts which may impress you, or at least interest you:

First of all, do you have any idea how far a light-year is? Well, light travels 299,793 kilometers per second. (Let’s say 300,000). Or if you prefer miles: 186,282 miles per second. There are 31 and a half million seconds in a year (31,536,000). So a light-year is 5,874,589,252,000 miles. Nearly 6 trillion miles. Six followed by 12 zeros. If you were a ray of light you would have to travel around the earth 250 million times in order to cover the distance of one light year.

The known Universe is 93 billion light-years in diameter. That’s 54 x 10 to the 22nd power. Or 5,400,000,000,000,000,000,000,000 miles. What’s the word for such a number? After quadrillion comes quintillion, then sextillion, then heptillion?

The sun is 80,000 miles in diameter, i.e. ten times the earth. Its mass is over 300,000 times that of the earth.

Here are the solar planets, listed in order of distance from the sun: Mercury, Venus, Earth (remember, Third Rock from the sun, the TV show?) Mars, Saturn, Uranus, Jupiter, Neptune and poor Pluto, recently demoted from planet to.... what? Asteroid? “Body”? Rock? No wonder nobody loves poor Pluto, it’s almost three billion miles away from us!

But even though Pluto is the most distant (former) planet, it is practically our next door neighbor, compared to stars.

Stars are very, very far. The closest stars are Proxima Centauri, Serius and Alpha Centauri. They are 4  to 5 light years away, which is 24 to 30 trillion miles! It is unlikely that humans will ever be able to physically travel to any star.

But compared to galaxies, even these distances seem small. Our own galaxy, the Milky Way, is 100,000 light-years across. Captains Kirk and Picard may be shooting across the galaxy in hyperwarp, but only on television.

And what about beyond our galaxy? There, the distances become even more unimaginable. We have a “neighbor” galaxy called Magellan. And you know how close this neighbor of ours is? Hundred and sixty thousand light-years!

You think that the sun is pretty big? Actually, it is a smallish fourth-class star. They even call it a ‘dwarf.’

Some stars are incomprehensibly large. They are called red giants. For example Antares and Betelgeuse. Betelgeuse is so large that if its center were the sun, its outer surface would reach Jupiter, which is five hundred million miles from the sun. This star measures a billion miles across, which is 125,000 times the earth! Just to complete one orbit around Betelgeuse with, say, something like our space shuttle would take our astronauts 172 years. Getting to Betelgeuse, which is nearly five hundred light-years away, would take till the end of time.

Here is a miniaturized version of some of the above: If the earth were a sand pebble on a beach in California (say one millimeter), the moon would be one inch away from our “pebble” and it would be half a millimeter in diameter. The sun would be the size of a peanut, and it would be about 20 yards away from the sand “pebble”. Pluto, the most distant (former) planet would be a third of a mile away. One light-year would be about five hundred miles from the beach in California: about where Salt Lake City is. The closest star - Proxima Centauri or Serius - would be like Chicago from our beach. Our galaxy, The Milky Way, would be fifty million miles across, or 250 times the distance earth-moon. Magellan, our “neighbor” galaxy, would be 80 million miles away.

Now put all of this on the surface of an inflating balloon (because we live in an expanding Universe). The distances between every galactic object increases at an accelerating rate so that all these figures will soon be doubled. Wow!leave comment here