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Astronomy: Back to quasars!

Astronomy: Back to quasars!

IMAGINE, light from the distant quasars proceeded for its travels towards our galaxy some eight billion years ago, or more. Yet the biggest telescopes, both optical and radio, have been observing them. The light is yet so remote that it is still not visible to the naked eye! These telescopes, those marvels of collective human ingenuity can see much farther, though. Like a chasing cop sees an escaping fugitive long way away, in a dark, dingy alley!

Imagine again that a cluster of thousands of galaxies located in the constellation Virgo (one of the zodiacs), lying at 50,000 light years (l.y) is rushing away from the Milky Way at the speed of 750 miles each second! The Corona Borealis (the Crown of the South) at the distance of 950 million (l.y.) is fleeing at 13,400 m.p.s. from us. A super cluster in Bootes (Herdsman), at an incredible distance of 1.7 l.y is chasing dunno what, at 24,400 m.p.s.

All of these galaxies, and millions more of them are lying stealthily in the background of one constellation or the other. ‘Galaxies by the million’ sounds like a joke! That too tucked behind a zodiac, a single constellation, yet it is as true as God made apples.

These are just a few of the crazy examples to show you how absolutely important is your knowledge of the map of the skies; Besides other things. I can go on and on, for I have had little else to do in life ! But as I always say, you ought to know the basics. Your school and college level physics and chemistry will help you reach for the stars. It will launch you into astronomy, whether boys or girls.

Imagine that a galactic object like quasar is racing away from its source at 80 per cent the speed of light. Our own group of galaxies move much more sedately — no faster than one per cent the speed of light.

But anyone watching us from a quasar — imagine! — will watch us racing much faster than that. That is because s/he will be seeing us that far back in time. Say, 10 or 11, or even 12 billion years back! Forget for a while whether the Solar System had come into being or not. Now, this seems to prove that quasars had long ‘overtaken’ our space in the universe a while before our galaxy was even ‘conceived’!

Is the universe round, so that having gone so far away in their journeys they have now ‘reached the bend’ and are now turning back on themselves.

We ought to be able to substantiate the very raison d’etre of quasars. Why they are what they are, after all? What role do these stupendous bodies tend to play in the cosmic scheme of things? But first the reason, or the cause of their existence.

It seems that when the universe came into being, some 15 billion years ago, and the accumulated matter split up into huge pieces, each bigger than a big galaxy, some of it ‘refused’ to further split and convert into galaxies. The conditions — intense heat reaching billions of degrees Kelvin, and other factors — disallowed the pristine manufacturing of atoms, the earliest atoms inside the super-heated quasars.

Thus the bodies remained in their original form later to be christened as quasars, or quasi-stellar Radio sources. Here the question is: why did quasars not develop into proper galaxies with the passage of time, after the universe cooled a bit allowing appropriate atoms to come into being?

The answer is: you never know they may have. After all we are watching them as they ‘were’, not as they ‘are’. Their light has barely reached us telling the story as it was and not as it is. The ‘is’ will be revealed a bit later — a few billion years from now!

Instead of closing our discussion on complex things in astronomy, at this stage, a whole ‘Pandora’s Box’ is revealed! For better understanding we ought to know a myriad terminology employed in astronomy and astro-physics. Without that we do not hope to get very far. Just imagine that someone asks you: what is the albedo of this body or that, or what is one parsec, or that what is Olber’s paradox etc? What chance do you stand before such questions?

I will place a whole lot of such questions, and their answers for you to know and remember. Most of the terminology employed in astronomy/cosmology. You will be required not only to keep a cutting of the article, but also keep those answers ready for future use. This will be of great help.

The Q/A session will be dealt with in alphabetical order, to serve you in good stead. Commencing next issue! I am yearning for the time when my young friends overtake me in astronomical knowledge. Good bye and God Bless.

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