Finding Distance to Sirius Using Parallax Method

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    Method Parallax
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Discussion Overview

The discussion centers on the methodology for determining the distance to the star Sirius using the parallax method, specifically focusing on how measurements are obtained with Earth-based telescopes. Participants explore the concepts of angles, distances, and the practical steps involved in the measurement process.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant inquires about the initial steps to obtain the parallax angle and distance data for Sirius, expressing confusion about how these measurements are made.
  • Another participant suggests that measuring angles between stars is possible, prompting further questions about the nature of such measurements.
  • A participant clarifies that the observer can be considered the third point in the triangle formed by the Earth’s position at different times of the year and the star Sirius.
  • Discussion includes the concept of using the Earth’s orbit as a baseline for measuring angles, with one participant explaining how to visualize this using a hand gesture to demonstrate parallax.
  • Reference is made to historical instruments like the octant, though there is uncertainty about which modern methods are currently used in astronomy.

Areas of Agreement / Disagreement

Participants express varying levels of understanding regarding the measurement process, with some clarifying concepts while others remain confused. There is no consensus on the specific methods used today, and multiple viewpoints on the measurement techniques are presented.

Contextual Notes

Limitations include a lack of detailed explanation on the specific instruments and techniques currently employed in parallax measurements, as well as assumptions about the observer's perspective and the geometry involved.

Who May Find This Useful

This discussion may be of interest to individuals studying astronomy, particularly those curious about measurement techniques and the practical application of parallax in determining stellar distances.

yukkuy
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how will you find the distance to the star sirius using parallax method using eath based telescpoes?

i know the distances and angle in association with the equation...but i don't get how u accuatly get those data. The very first step in achieving those data.

like for eg ...the distance is 2.63 parsecs and the parallax angle is 0.38 arcseconds...how did they actually get those data ?
i know if you find one of those data ...it will help the forumlar :)
just don't understand how they got them :)
 
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Look at the sky - can you measure an angle between any two stars (or other objects)?
 
Borek said:
Look at the sky - can you measure an angle between any two stars (or other objects)?

to be honest i don't really understood that
but ... measuring the angle between any two stars would be ...0? cause u can't have a angle unless there's 3 points ?
 
You are third point.
 
sooo...The point is at say june ...then the second point will be at around december (earth revolve ...180*)
...so that forms the baseline of my triangle, and with sirius makes the 3 . but how do i measure those angles with telescopes?
 
It really isn't that difficult. See for example

http://en.wikipedia.org/wiki/Octant_(instrument )

Bear in mind this is an outdated instrument, designed hundreds of years ago.

There are many ways, to be honest, I have no idea which one is used routinely in todays astronomy. Probably more than one though.
 
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I didn't follow the link above so I apologize if this is a repeat. What they do is using that base line technique as described above, they watch/measure how the star moves laterally with respect to the backround sky from each respective point in space ( measure once in June and once again in December). Using a little trigonometry you can obtain the inside angle by creating a right triangle and doubling the quantity. This can be demonstrated rather easily. If you extend your hand out directly in front of your face while holdinh your hand in a fist with your thumb up, alternate closing one eye at a time and your thumb will appear to shift positions even though your hand hasn't moved. Hope that helps.

Joe
 

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