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Home Q & A Board Science-Related Homework Help Physics Astronomy
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Groanier Groanier
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6 years ago
The fact that the properties of the Universe are close to the dividing line between open and closed Universes refers to the _______________ problem.
 
  Fill in the blank(s) with correct word

Question 2

Why do sunspots occur darker than the rest of the Sun's surface?
 
  What will be an ideal response?

Question 3

The Universe is _______________ because it looks the same in any direction you observe it.
 
  Fill in the blank(s) with correct word

Question 4

What causes auroras and where are they most prominent on Earth?
 
  What will be an ideal response?

Question 5

The cosmic microwave background radiation comes from the time when neutral hydrogen atoms formed in the process of _______________.
 
  Fill in the blank(s) with correct word
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wrote...
#1
6 years ago
Answer to q. 1

flatness

Answer to q. 2

Sunspots are cooler than the photosphere with a temperature of about 4200 K. The photosphere has a temperature of about 5800 K. Because the total amount of energy radiated by a surface depends on its temperature raised to the fourth power, sunspots look dark in comparison.

Answer to q. 3

isotropic

Answer to q. 4

Coronal mass ejections erupt from Sun's surface, particles are blown off by solar wind, hitting Earth's magnetic field and exciting the particles in the Earth's atmosphere, creating an amazing light display.

We see the emission lines from gases in Earth's upper atmosphere that are excited to glow by a complicated interaction with the solar wind and Earth's magnetic field.

Answer to q. 5

recombination
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