Wednesday, July 22, 2009

July 22 Eclipse

Dear Sage, This morning while on our way to school, I told you guys “Hey, there will be an eclipse today: An eclipse is when the Sun gets slowly eaten by a giant dragon in the sky. But because it is so hot the dragon eventually spits it out after few minutes of trying to swallow it.” You guys were unimpressed and told me “We know what an eclipse is. We studied it in school.”

Smart ass.

Usually, nothing comes between the rays of the sun and the Earth (Just like Brooke Shields and her Calvin Klein Jeans.) But in regular intervals, the moon crosses the path in the sky in front of the sun. The shadow it casts on the Earth is the one we view as an eclipse. Depending on where you view this event, the moon’s shadow may totally blot out the sun from the sky (total eclipse) or you may just see a part of the sun darkened by the moon’s shadow (partial eclipse)

I have yet to witness a Total Eclipse. But it really is a cool event. It’s like the night descending in the middle of the day and staying briefly for a visit, then slowly yielding the heavens again to the light of day. During that brief interval, the chickens roost and the stars become visible.

During one total eclipse that happened in the early part of the 20th century, a prominent astronomer was able to observe that the position of the stars near the sun appear to be different during a total eclipse.

This simple observation proved the accuracy of General Relativity. The erstwhile crazy theory that a massive object (like the sun) can actually bend space finally gained acceptance among the world’s astrophysicists. A massive object like the sun can distort the “Flat” surface of space. In doing so, the lights from the stars that pass by its vicinity are "bent" because they have to travel a curved path instead of going straight to Earth. Which explains why the stars near the sun in a Total Eclipse appear to have changed position.

Remember at the basement of SM mega mall? There is this huge, black, circular funnel where we let coins spin around it until it reaches the center where it eventually drops out of sight? like in the youtube video below...

It is a good illustration of General Relativity. It actually represents a very massive, very dense singularity. The density of a singularity is so… huge (when you grow up, you will chastise me for this understatement) that it does not just bend light when it passes by its vicinity, it actually sucks it into the hole and does not let it escape. That's why a singularity is also know by another name, "Black Hole."

I bet they have yet to teach you that in 4th grade, huh? Huh?

1 comment:

tin-tin said...

didn't see the eclipse. nasa office na kasi ako

Letters to my kids about their childhood adventures

To Sage, Sabe, Sade & 3Stan

To Sage, Sabe, Sade & 3Stan