"An astronomer measures the angle to a star relative to the Big Dipper constellation at two times in the year, exactly six months apart. In each case the angle is 65 degrees."
It asks me to determine the baseline length in AU and the distance to the star in AU.
You see I've worked with this before where it's asked me to determine an unknown distance using an angle and the length of the side. I've reviewed the book several times but I'm unable to find any explanation on how to determine this. Would anyone be willing to shed some light? Thanks.
It asks me to determine the baseline length in AU and the distance to the star in AU.
You see I've worked with this before where it's asked me to determine an unknown distance using an angle and the length of the side. I've reviewed the book several times but I'm unable to find any explanation on how to determine this. Would anyone be willing to shed some light? Thanks.
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The baseline length is how far the Earth moves in six months. That is 2 AU.
But since the two lines from Earth to the star are parallel, the star is very far away. Mathematically, it's infinitely far away. In practical terms, the closest it could be depends on the accuracy of the measurements. It could be 1000 light years.
But since the two lines from Earth to the star are parallel, the star is very far away. Mathematically, it's infinitely far away. In practical terms, the closest it could be depends on the accuracy of the measurements. It could be 1000 light years.
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Big Dipper asterism is within Ursa Major constellation. Big Dipper is sperad over 20º to 30º; so which point of it you are measuring from and say 'Yes, this is 65º' ?
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This is a question about finding the distance to a star based on its parallax.
You have a baseline across a 6 month period of twice the earth's orbital radius, or 2 AU.
The distance to the star is far far away, as you have stated no angular difference between the two measurements.
This is just a trigonometry and triangle problem. Does that help without any more work?
You have a baseline across a 6 month period of twice the earth's orbital radius, or 2 AU.
The distance to the star is far far away, as you have stated no angular difference between the two measurements.
This is just a trigonometry and triangle problem. Does that help without any more work?
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