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Author Question: What is Tunguska? A) the site of an asteroid impact that occurred in Siberia in 1908 B) a ... (Read 69 times)

Yi-Chen

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on: Jul 27, 2018
What is Tunguska?
 
  A) the site of an asteroid impact that occurred in Siberia in 1908
  B) a postulated binary companion to the Sun thought to be responsible for mass extinctions
  C) a long period comet that struck Jupiter in 1994
  D) the Gulf of Mexico basin that is the crater of the asteroid impact that caused the mass extinction of the dinosaurs 65 million years ago
  E) a newly discovered moon of Pluto

Question 2

Suppose you discovered a star made purely of hydrogen and helium. How old do you think it would be? Explain.
 
  What will be an ideal response?


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ngr69

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Reply #1 on: Jul 27, 2018
Answer to Question 1

A

Answer to Question 2

A star made of only hydrogen and helium would have to be among the first generation of stars ever born, arising out of the primordial mix of elements that came from the Big Bang. The oldest stars we know about are over 12-15 billion years old and star made of only helium and hydrogen would have to be at least this old. Note that no such star has ever been discovered.


Yi-Chen

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Reply 2 on: Jul 27, 2018
Thanks for the timely response, appreciate it

miss_1456@hotmail.com

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Reply 3 on: Yesterday
YES! Correct, THANKS for helping me on my review

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