Asked by: Marilou Triñanes
science space and astronomy

How do they determine the distance of a star?

Last Updated: 5th June, 2020

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Astronomers estimate the distance of nearby objects in space by using a method called stellar parallax, or trigonometric parallax. Simply put, they measure a star's apparent movement against the background of more distant stars as Earth revolves around the sun.

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Similarly, you may ask, how is the distance to a star determined?

Astronomers can measure a star's position once, and then again 6 months later and calculate the apparent change in position. The star's apparent motion is called stellar parallax. The distance d is measured in parsecs and the parallax angle p is measured in arcseconds.

Likewise, what is the most accurate way to determine the distance to a nearby galaxy? 1 Answer. Oscar L. It's called "parallax". Basically you look at how much the star appears to move in the sky as a result of the earth actually moving on its orbit aroun the sun; the more the star seems to move the closer it is.

how is Parallax used to measure the distance to stars?

To measure large distances, such as the distance of a planet or a star from Earth, astronomers use the principle of parallax. Here, the term parallax is the semi-angle of inclination between two sight-lines to the star, as observed when Earth is on opposite sides of the Sun in its orbit.

How did we measure the distance to the sun?

When astronomers measure the parallax of an object and know the separation between the two positions from which it is observed, they can calculate the distance to the object. To calculate the distance to a star, astronomers observe it from different places along Earth's orbit around the Sun.

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