July 22 promises a solar eclipse that will be visible in many regions in India. The moon will hide the main disc of the sun and only the outer portions will be visible. A truly amazing sight.
Celestial drama : School kids watch a solar eclipse.
Remember the scene from Prisoners of the Sun where Tintin is tied up, ready to be burned alive? Tintin knew that the Moon was going to hide the Sun that day, and he told the Inca chief there would be an angry sign from the Sun if they killed him. Then the Sun became dark, the Incas were terrified and Tintin was set free. Tintin was saved by what we call an eclipse. To be precise, an eclipse of the Sun, as Thomson and Thompson might have added.
As the Moon goes around the Earth, sometimes it comes exactly between the Earth and the Sun, and throws a shadow that may reach the Earth. A person standing at the shadowed portion on the Earth will not be able to see the Sun because the Moon would block the view. Depending on where the person is standing, the Sun might appear to be either totally blocked, or partially blocked. One calls it a total or a partial solar eclipse.
One such solar eclipse is going to take place on July 22, and some parts of India will be among the shadowed region on Earth that day. If the sky is not otherwise covered by monsoon clouds, people watching from certain places (like Mumbai, Indore, Varanasi, Patna and so on) will see a spectacular sight. As the Moon will hide the main disc of the Sun, the outer portions of the Sun will become visible. A solar eclipse offers the only chance when this ‘corona’ (which means crown) can be seen. Along with the dazzling corona, some planets like Venus and Mars will also be seen because the sky will momentarily become dark.
People from other places in India will see a partially blocked Sun. It will last for a few minutes though, since the Moon is moving, and the Earth is also rotating.
Fifteen days after the solar eclipse, when the Moon reaches the opposite side, another eclipse will take place. This time the Earth will throw its shadow on the Moon, and the Moon will appear dark for some time on the night of August 6.
There was a lunar eclipse on July 8 (that lunar eclipses occur only on full moon nights, and solar eclipses, on new moon days), but it was not visible from India. This means that by the time the Moon entered the Earth’s shadow, India had moved to the daylight side.
This instance of three eclipses occurring within a month might strike you odd, but if you think about it, it would not appear so any more. For one thing, lunar eclipses are quite common, because the Earth throws a big shadow, bigger than that thrown by the Moon, because the Earth is bigger than the Moon. This increases the chance of the Earth’s shadow falling on the Moon. One must take some precautions in viewing eclipses though. Lunar eclipses can be watched without any special gear, but for solar eclipses one should use filters to protect the eyes.
Food for thought
• Why don’t we see eclipses on every full and new moon?
The Moon’s orbit is slightly bent relative to the orbit of the Earth around the Sun. Most often, the Moon is slightly above or below the plane of the Earth’s orbit, and so its shadow does not reach the Earth, or the Earth’s shadow does not fall on it.
• Why does the Moon look dark red during a lunar eclipse?
Although most of the sunlight is blocked by the Earth, some light does reach the Moon after being scattered through the Earth’s atmosphere that makes it look red.
• Why don’t planets like Venus eclipse the Sun?
Venus does come between Earth and the Sun at times, but its size is too small to block the Sun completely. It is a coincidence that the Moon and the Sun appear to have the same size from the Earth, although their sizes are very different in reality. This coincidence makes the solar eclipse a wonderful spectacle.
Get your Nickgoggles
Nick, the kids’ channel invites all kids to join in and witness the Solar Eclipse! Since it is not safe to view the eclipse with your naked eye; Nick gives its viewers really funky and cool “Nickgoggles” with a special safe filter to look directly at the ‘diamond ring’ that the sun and moon form.
To get your hands on the goggles all you have to do is log on towww.nickindia.com or SMS Solar
From history
Eclipses offer scientists a chance to do some special experiments that cannot be done otherwise. And since the eclipses can be seen from a limited region on the Earth, scientists often organise expeditions to various places in order to watch eclipses.
One such important expedition came to India in 1868 to witness a total solar eclipse on August 18. Pierre Jules César Janssen came from France to Guntur to observe the eclipse, and the then Madras Observatory sent a few astronomers to places like Machilipatnam and Belgaum. They all hoped to study the spectrum of sunlight at the time of the eclipse. Scientists had at that time established that one could identify substances with the spectra of their light. During the eclipse, astronomers discovered a bright yellow line in the spectrum that no one had seen earlier. They later found it to be the signature of a new type of gas, which they named ‘helium’, from the Greek word ‘helios’ for the Sun, because they had first found it in the Sun.
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