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You measure the parallax angle for a star to be 0.1 arcseconds. What is the distance to this star?

Answer 1

Lydia Allen

10 parsecs =32.8 light years = 2.06 X 10^6 AU.

Distance is calculated using the formula d = 1/(radian parallax angle) AU.

Here, the distance is 1 parsec for a parallax angle of 1 second.

Therefore, 10 parsecs = 10 X 206364.8 AU for 0.1 second.

62900 AU is almost equal to one light year (ly).

#= 2062648/62900= 32.79 ly.

In this instance, the precision for the angular measurement will be up to 0.001 seconds. The answer is provided for this precision. This is significant when converting from one unit to another. For example, if the angular measurement is 3-sd.100 seconds, the answer is 32.8 ly.

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Answer 2

Leah Abbate

The distance to the star can be calculated using the formula: distance (in parsecs) = 1 / parallax angle (in arcseconds).

So, if the parallax angle is 0.1 arcseconds, the distance to the star would be 1 / 0.1 = 10 parsecs.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.