Distance to stars from my house using the parallax technique?

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Using the parallax technique to measure the distance to stars from home is highly challenging due to the required precision. A star at 1 parsec shows a parallax of 1 arcsecond, and most stars are much farther away, resulting in significantly smaller parallaxes. Measuring over a month would yield even smaller angles, around 1/50 of an arcsecond, which is beyond typical amateur capabilities. The Earth's atmosphere further complicates accurate measurements, limiting resolution to about 0.5 arcseconds. Overall, achieving reliable parallax measurements from home is impractical without specialized equipment.
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Is it possible to find the distance to stars from my house using the parallax technique? If I can how close does a star have to be to be measured in a month instead of six months?
 
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Stratosphere said:
Is it possible to find the distance to stars from my house using the parallax technique? If I can how close does a star have to be to be measured in a month instead of six months?

If I didn't know any better I'd say you were trying to do this yourself.

A star at a distance of 1 pc displays a parallax of 1 arcsecond. There are no stars closer than 1pc, so even the nearest are going to display a parallax siginificantly smaller than 1 arcsecond. And these are annual parallax numbers. If you want to try the measurements in only a month, you can expect much smaller parallaxes, on the order of 1/50 of an arcsecond for typical stars.

So, unless you have that kind of resolving power, I'd say it's out of the question.
 


So would I be able to measure things that would require a longer amount of time?
 


Stratosphere said:
So would I be able to measure things that would require a longer amount of time?

Probably not. Like I said annual parallaxes are going to be less than one arc second. Significantly less, but it's probably even optimistic to hope to get some in the neighborhood of 1/10 of an arcsecond. Annually. Also, given the fact that even under the best of seeing conditions the Earth's atmosphere limits resolution to about .5 arcseconds, it seems a daunting task indeed.

Getting down to .5 arcseconds isn't actually that hard, and only requires a ~8-10 inch diameter telescope. But taking precise enough measurements to detect the parallax, owing to the damned atmosphere, would be near impossible for an amateur (I think).
 


You can do the math with simple trigonometry. The diameter of the Earth's orbit around the sun is approximately 186 million miles [a very convenient number - 1000 light seconds]. That forms the base of the parallax triangle you have to work with. One light year works out to around 6 trillion miles - a pretty large number compared to the diameter of Earth's orbit. You need a very accurate [and expensive] devise to reliably measure such small angles.
 


OK, these answers are better than mine. Which was going to be 'Depends on how wide your house is'.
 
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