Watching Jupiter and Venus

Photo credit: NASA and JPL. Image from Wikimedia Commons. 

This image is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. 


Some of the readers of this blog have been telling me that it is difficult to see Mercury. In Bengaluru, the Sun will rise at about 6:40 AM tomorrow. I have set the alarm to wake me up to see mercury at 6 AM. But it is not always easy for me to get up that early!

I have found a good solution to the problem. Tomorrow, the Sun will set in the West, at about 6:30 PM, in Bengaluru. After seven PM, I will be able to see two bright planets in the west. I saw them today. The brighter one is Venus, and it will be lower in the sky than the other. The other one will be Jupiter.

I am excited about these planets. More than four hundred years ago, in the year 1610, the Astronomer Galileo started observing these two planets with a home-made telescope. He saw that all of Venus was not uniformly lit. It has phases, like the moon, showing different parts of the planet covered in light at different times. Was it because Venus was spherical and Sunlight covered different parts of it as it moved around the Sun? This was a dangerous thing to talk about in those days. Most people did not believe that planets were going around in rough circles while Sun stayed at the centre.

The fact that there were three small objects going round Jupiter also supported the idea that Sun could be the center of our solar system. Galileo could see only three of these objects, moons of Jupiter. These ideas made people realize that the earth was not flat. It was also spherical. Then astronomers found out that the path of each planet round the Sun was an ellipse, a stretched-out circle.

People then started exploring the earth with long voyages by ship, trying to go round the earth. Life on earth changed in a big way, when those  explorers discovered a new continent, America!

Do planets affect the life of people on earth? Well, Venus and Jupiter did! Not in the way astrologers think, but Venus and Jupiter did make us think correctly about our own earth and about the Sun and other planets!

In India, people call Jupiter Guru, the teacher! Yes, Jupiter did teach us something valuable!

Srinivasan Ramani    

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