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Is it true or false astronomers have calculated the parallax angles of millions of stars?
Wiki User
∙ 10y ago
The answer is: yes, just about, maybe.
Astronomers had catalogued over 2 million stars with parallax values.
However many of the values are estimates and some of the angles are very small.
Wiki User
∙ 10y ago
Wiki User
∙ 11y agoImagine this:
There's a tree on the other side of the river. You'd like to know how far it is from you,
but there's no way to stretch a measuring tape across the river. What do you do ?
Try this:
-- Mark two points on the ground, 100 feet apart, both on the same side of the river,
where you are. Call them points 'A' and 'B'.
-- Stand at Point-'A'. Measure the angle between Point-"B" and the distant tree.
Write it down, then walk along your side of the river, over to Point-'B'.
-- Stand at Point-'B'. Measure the angle between Point-'A' and the distant tree.
Write it down.
-- You have a triangle, formed by the tree, Point-'A', and Point-'B'. You know the
length of Side-AB, and you know the angles from each end of it to the tree.
With only a little bit of trigonometry, you can calculate the distance to the tree.
===============================
Now, over to "parallax".
-- The distant star is the tree. You can;t stretch a measuring tape to it from Earth.
So you use two points that you can reach, and measure the angles from each point.
-- The two points are the places where the Earth is, on opposite sides of its orbit
around the sun, 6 months apart.
The distance between the points is roughly 186 million miles.
When we go from one point to the other, the angle toward the star changes slightly.
The amount that direction changes in 6 months is that star's parallax.
If we measure the direction toward the star from each point, we can calculate
the distance to the star.
Wiki User
∙ 13y agoNo, only up to about 1600 light-years or so. Beyond that, the parallax angle becomes too small to measure with any reasonable degree of precision. This is with current technology; we can easily imagine that in the future, with improved technology, this range can be extended.
Wiki User
∙ 12y agoNo, the parallax would be too small to measure. With current technology, a parallax can be used up to a distance of about 1600 light-years - the farther away the start that is measured, the more inaccurate is the distance calculation.
Wiki User
∙ 15y agoNo it only works out to a certain distance.
Beyond this you move in to the field of red shifting measurement.
Wiki User
∙ 14y agodescribe the parallax method of determining distance to stars
Wiki User
∙ 10y agoTrue, just about.
They have done it for about 2.5 million stars.
Wiki User
∙ 11y agoNo.
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Why do we measure the movement of stars?
Parallax is the apparent change in position of an object when you look at it from different angles. Astronomers often us parallax to measure distances to nearby stars. This method can be used to determine stars' distances up to 400 light-years from Earth.
What is the effect of distance from an object on parallax angles?
The parallax should get smaller and harder to notice although in astronomy there are techniques used to find the parallax of stars by using the Earth's position around the sun to find the distance of the stars.
Why can smaller parallax angles be measured by telescopes in Earth orbit?
Earth's atmosphere does not limit a telescope's resolving power.
How can be the distance between the sun and the earth measured?
To measure the distance from the earth to the sun, or to any star for that matter astronomers use a form of trigonometry called Parallax (see related Link). Simply put, think of measuring a known distance (the larger the better) and measure the angles to the sun at the same time at each end of that baseline. Using the Angle-Side-Angle formula, (See related link #2) the lengths of the other two sides can be calculated
How did aristotles' inability to detect parallax lead him to propose a geocentric model of the solar system?
He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect.He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect =) Hope it helped. I had the same question
Why do we measure the movement of stars?
Parallax is the apparent change in position of an object when you look at it from different angles. Astronomers often us parallax to measure distances to nearby stars. This method can be used to determine stars' distances up to 400 light-years from Earth.
Why were early astronomers unable to detect stellar parallax?
Pressumably, they didn't have the high-precision devices required to measure those angles. You must consider that we are talking about extremely small angles - even the closest star has a parallax of less than one arc-second (1/3600 of a degree).
Which stars have the largest parallax angles-?
the stars nearest Earth
Why can't astronomer measure the parallax of a star that is a million lights away?
The farther the object, the smaller its parallax. In this case, the parallax is about 1/300,000 of an arc-second (and an arc-second is 1/3600 of a degree) - way too small to measure. Perhaps you will eventually find a way to measure smaller parallax angles.
What is the effect of distance from an object on parallax angles?
The parallax should get smaller and harder to notice although in astronomy there are techniques used to find the parallax of stars by using the Earth's position around the sun to find the distance of the stars.
Why can smaller parallax angles be measured by telescopes in Earth orbit?
Earth's atmosphere does not limit a telescope's resolving power.
Why were ancient people unable to detect stellar parallax?
they couldn't measure small angles
How can be the distance between the sun and the earth measured?
To measure the distance from the earth to the sun, or to any star for that matter astronomers use a form of trigonometry called Parallax (see related Link). Simply put, think of measuring a known distance (the larger the better) and measure the angles to the sun at the same time at each end of that baseline. Using the Angle-Side-Angle formula, (See related link #2) the lengths of the other two sides can be calculated
Do all-stars have measurable parallax angles?
No, only the closer ones have a parallax that is large enough to be measured. The first star to have its parallax measured was 61 Cygni, measured by Bessel in 1838 and found to be at a distance of 10.3 light years, later corrected to 11.4. The closest star Proxima Centauri has a parallax of only about 0.7 seconds of arc. Before then the absence of parallax for the stars was considered an important part of the case that the Earth cannot be revolving round the Sun.
How did aristotles' inability to detect parallax lead him to propose a geocentric model of the solar system?
He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect.He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect =) Hope it helped. I had the same question
How did the Aristotle's inability to detect parallax lead him to propose a geocentric model of the solar system?
He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect.He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect =) Hope it helped. I had the same question
How did Aristotle inability to detect parallax lead him to propose a geocentric model of the solar system?
He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect.He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect =) Hope it helped. I had the same question
