Wednesday, November 02, 2005

Who invented the telescope ?

If you said Galileo, the answer is wrong !

It is believed that the telescope was invented in 1608 by Hans Lipperhey.

Most books mislead us into thinking that Galileo invented the telescope; he did not. But he was the first to point it towards and sky and use it for observing the heavenly bodies.

He improved the power of the telescope and was able to observe many remarkable things in the Solar System including the four large moons of Jupiter ( which we now call Galilean Moons). He observed the irregular features on our Moon; observed that Venus also had phases just like our Moon. He was also one of the first Europeans to observe Sun spots. He also obsereved the Milky Way and noticed that it had billions of stars. He published his observations in a short treatise called Sidereus Nuncius ( Starry Messenger).

His observations helped him in strengthening his belief about a Heliocentric Model ( all planets go around the Sun) as opposed to the current belief at that time, the Geo-centric Model ( all planets go around the Earth). Then began Galileo's trouble with the Catholic Church. He was forced to say that he was mistaken about the Heliocentric model in order to escape death. His famous last words which he murmured during the trial loosely translated were 'and yet it moves'. He was placed under house arrest for many years. He became completely blind after that, yet, he continued to teach and write till his death!

It was not until 1992 that the Catholic Church finally accepted the Heliocentric model !
This was 350 years after the death of Galileo !

Nicholas Copernicus is considered by many as the the Father of Modern Astronomy because of his Heliocentric Model theory, which paved the way for a revolution.

Thursday, October 27, 2005

The far side of the moon...

Did you know that we're always looking at the same hemisphere of the Moon from Earth ?

The Moon rotates synchronously with Earth and so we can only see one side of it from Earth; which means that we can never see what is on the other side of the moon from earth ! The side that we see is called the Near Side of the moon while the other side is called Far Side of the moon. The only people who have seen the far side are the astronomers who landed on the moon. Also, this is not to be confused with the Dark Side of the moon - this is the shadow region on the near side of the moon; in plain language it means the dark parts on the near side on which there is no sunlight falling.

And here is another strange fact; the Moon is moving away from Earth each year ! This causes the Earth to slow down its rotation; so in a few million years, a day will be longer than 24 hrs ! And eventually, the Moon-Earth will be in synchronous locked rotation; which means that not only will we see only a part of the Moon (like now) but the Moon will be fixed in the Sky over a spot! The moon will not be visible from the other parts of the Earth !! This is like having a geo-stationary satellite !! The Moon will seem to be fixed in space above the Earth.

Such a phenomenon is observed in nature; the planet, Pluto and its moon Charon are such a locked -system !

Wednesday, October 26, 2005

Astronomy Vs Astrology

Contrary to popular belief; Astronomy and Astrology are different !! Whenever I tell anyone that I am majoring in Astronomy and Astrophysics; one of the most common queries is about horoscopes and forecast. It always amuses me when educated people make this mistake !

Astronomy is the 'Science of stars' while Astrology is not even considered science. What quality qualtifies science and acceptance ? Well, this is something subject to many debates and controversies; an easy way to explain would be saying that science is based on facts and principles. For example,we can predict the position of any planet in the solar system with great accuracy. But we cannot gurantee the affect of the postion of Saturn on you today. That is because Astrology is based on probability and statistics. All the predictions are made by intelligent guesses. Astrology uses the concept of solar system and planets. Other than that, they are quite different.

My mom is studying Astrology and we have long discussions about the differences between the two. Its very fascinating. I think human nature would like to believe predictions about the future however vague they seem. I am not trying to say that Astrology is nonsense ( I read my horoscope everyday - I just don't believe in it ). So according to me, Astrology is just good time pass ; not something that we can take seriously.

Astronomy on the other hand is one of my greatest passions ! This blog is about this topic after all :-)