Thursday, May 28, 2009

The Stars at Night

By Yusuf M. Adamu PhD
Excerpts from my forthcoming book Conversation with the Earth


The first thing that fascinates Khadijah and Ahmad in their first night in the village is the night sky. The moon is gone but the night was well dotted with some tiny lamps, many of them that the two children could not count. “Uncle, I have never seen so many stars like this,” said Ahmad
“What are stars?” Khadijah asked before Ali could respond
“You are very impatient” Ahmad said
“Do not worry Ahmad, Khadijah look up,” said Ali
They all looked up at the sky. Uncle Ali began explanation, “Stars are like our Sun, and they are lamps in the sky. There are many of them up there no one knows how many they are”
“If they are like the Sun why are they not as big and as bright?”
“They are not as bright because they are very far away” Uncle Ali replied
“How far away are they?” Asked Ahmad with more curiosity
“Yes, we want to know,” said Khadijah
Uncle Ali sighs and said, “Well, the Sun is about One Hundred and Fifty Million Kilometers from the earth”
“One hundred and fifty million kilometers?” Ahmad asked in astonishment
“Yes, and it is the closest star to the earth”
“But what is a million?” Khadijah ask
“One million is one thousand times one thousand” replied Ahmad confidently.
“That means the Sun is One Thousand time One Thousand time One hundred and fifty kilometers away from the earth,” Khadijah said
“That’s right.” Replied Uncle Ali wondering how to explain to these children how far stars really are.
As he expects, Khadijah asked the question “But uncle if the Sun is the closest Star how far are the twinkling stars we that are out there?”
This is a question he expects and he finds it very difficult to explain in such a way that Khadijah will comprehend, although he is hopeful that Ahmad might grasp something. In any case, he has to try and he began “apart from the Sun, the nearest star from the earth is very far and far away, it is 66,666 times farther away than the Sun” Khadijah looked confused “I don’t understand this” she confessed. Uncle Ali could understand why she is confused, but he is not sure if Ahmad has understood him and waited to hear his response.

“Uncle, you are right, Stars are very far and far away. My question now is that why do some look white, some blue some yellow?”
Uncle Ali was surprised with the question but he reasoned that they are outside in the night watching the stars. He smiled and said “the colours of the stars is simply telling us how far and how hot they are, the yellow stars like the Sun are not as far as the rest and are not as hot. The blue stars are farther and hotter than the yellow while the white stars are hotter and farther than all the rest. I hope you understand Ahmad”
“Yes uncle, thank you, we have learnt so much tonight. It is getting cold, I think we should go in” Ahmad suggested.
“Yes, we learnt a lot, but uncle you still did not answer my question, how far are the stars?”
“You Khadijah, you are too stubborn. You are too small to understand. When you grow up, you will understand. But for now just take it that the stars are very far and far away, that is why they look tiny”
“OK, but where do the stars go in the day?” Asked Khadijah
“They hide” Ahmad replied
“Is that true uncle?” Khadijah asked again
“No, they are there in the sky. We don’t see them because the Sun is brighter.” Said Uncle Ali as he draws Khadijah and Ahmad and lead them into the house.