Solve Parallax Equation: Find Distance to Star in km & ly

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The discussion focuses on solving the parallax equation to determine the distance to a star using the formula D=(d/2)/tan(theta/2). Given d as 300 million kilometers and theta as 5*10^-5 degrees, the calculated distance is approximately 343,774,677,078.41 km. The conversion to light years was initially estimated at 27 light years, but it was suggested that this conversion needs to be recalculated for accuracy. Participants confirm that D and d must have the same units, and the correct approach to the conversion is emphasized. The conversation highlights the importance of careful calculations in astronomical distance measurements.
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please can somebody help me with this parallax equation:

D=distance to star
theta=angle
using the rule D=(d/2)/tan(theta/2)
when d = 300*10tothe6
and theta = 5*10tothe-5

what is the distance to the star in km and light years?
 
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What's the problem?

(d is in what units?)
 
d is in km and theta is in degrees.
This is as close as i can get:
for this answer i get a result of:

343774677078406.6587981892079753

So, is this answer the number of km?

what is this answer in exponential form? ie: 34 * 10tothepower13?

1 light year is 9.467*10tothepower12, so in light years i think the distance will be:
27 light years

Please let me know if i am right
 
D and d have the same units. Your value for D in km is correct, but you messed up the conversion to light years. Do it over, more carefully.
 

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