Trish Jibben

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STARS
JAXA/SAO/NASA/NAOJ

• Trish Jibben
• Smithsonian Astrophysical Observatory
• Cambridge,MA

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What are Stars?
Astronomy Picture of the Day (February 21, 2007)
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What are Stars?

• Balls of gas burning billions of miles away

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What is the closest star?
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What is the closest star?
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Sun!
SOHO (NASA)
EIT (NASA)
MDI (NASA)
EIT (NASA)
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People

Middle Age
Born
Grow

What are Stars?
Old
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Stars change as they get older Just like people
Stars
But they change Slowly

Middle Age
Born
MDI (NASA)
Grow
HST (NASA)

What are Stars?
Old
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Stars are different sizes
White Dwarf
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Stars are Hot!

• The color of a star tells you how hot they are.

Hot
Cool
Hottest stars can get to be 90,000 degrees
fahrenheit!
Cool stars are about 5,000 degrees Fahrenheit
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Astronomy Picture of the Day July 20, 2006
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Some stars are close together
HST (NASA)
HST (NASA)
Some stars that look close are really far apart
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Some are VERY close!
HST (NASA)
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Stars are moving!
Stars Rotate
Stars move through space but it takes a long Time
to see them move
XRT (JAXA/SAO/NASA/NAOJ)
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Why do stars look like dots?
Close up the statue of liberty looks big!
If you move away from it. It begins to look
smaller
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Hellicopter
Airplane
Stars look like small dots because they are very,
very, VERY far away.
Space Station
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The sun is brightest star in the sky -because we
are close.
Because we are so close to the sun the light is
really bright and fills the whole sky up with
light! Daylight!
SOHO (NASA)
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Questions

• What would the sun look like if it were far away?
• What would stars look like if they were close?

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• Because the sun is so close we have to use
  special telescope to see it.
• Because other stars are so far away we have to
  use telescopes to see them too!