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For close-by stars, parallax can be used to gauge distances. But for the most remote stars observable, the distance is too great to use parallax. Those distances are determined using a variety of methods, depending on the type of star, the approximate distance scale, and other circumstances. Such methods would require a much greater theoretical understanding of the stars themselves as well as the structure of the cosmos at large scales.
What else can I help you with?
Edwin Hubble demonstrated that distant galaxies existed by measuring which type of stars?
Edwin Hubble used Cepheid variable stars to measure the distances to galaxies. These stars have a relationship between their luminosity and pulsation period, allowing astronomers to calculate their distance based on their observed brightness.
Why does the Cepheid distance method fail us beyond about 20 Mpc?
I don't know for sure how far this method actually works, but at large distances, it may be difficult to make out individual stars, and even more to identify them as belonging to a certain class of stars.
Do galaxies at very large distances look distorted?
Yes, galaxies at very large distances can appear distorted due to gravitational lensing effects caused by the bending of light by massive objects. This distortion can elongate or warp the images of distant galaxies, altering their perceived shapes.
When scientists look at very distant galaxies through powerful telescopes they see the galaxies as they were millions or billions of year ago. Why is this?
The vast distances involved means that the light we see left those galaxies a long time ago.
Why do scientists study distant galaxies to learn about galaxies?
Scientists study distant galaxies to understand the formation, evolution, and properties of galaxies over time. By observing galaxies that are far away, they can explore the universe at different epochs and gain insights into how galaxies have changed and evolved since the early universe. Studying distant galaxies also helps scientists refine theories about the laws of physics and the nature of the universe as a whole.
Edwin Hubble demonstrated that distant galaxies existed by measuring which type of stars?
Edwin Hubble used Cepheid variable stars to measure the distances to galaxies. These stars have a relationship between their luminosity and pulsation period, allowing astronomers to calculate their distance based on their observed brightness.
What is the most accurate way to determine the distance to a very distant irregular galaxy?
Cepheid variables
Where is the distant galaxy?
There are distant galaxies all around us - in all directions, and at varying distances.
Why was Henrietta Swan Leavitt's study of these stars important in the area of astronomy?
Henrietta Leavitt studied Cepheid variables, a certain type of variable star with brightness that varies in a very regular cycle. By studying Cepheid variables in the Magellanic clouds, she discovered a simple relationship between the brightness of a Cepheid variable star and the length of time the cycle takes to repeat itself. To do this she used the fact that all such variables in the clouds are at the same distance from us, approximately. This allowed her to calculate the absolute magnitude of the star just by measuring the time period of the variation in brightness. The importance of this technique is that Cepheid variables can be found in more distant galaxies, and this provides a yardstick for finding out how far away they are. All you have to do is find a Cepheid variable in a galaxy and measure its variation period, then you know its absolute magnitude. You already know its apparent magnitude so it becomes possible to calculate how far away it is. This is one of the methods that astronomers used in the early 20th century to reveal the unexpectedly huge distances of other galaxies in the universe. Let's hear it for Miss Henrietta Leavitt!
Why does the Cepheid distance method fail us beyond about 20 Mpc?
I don't know for sure how far this method actually works, but at large distances, it may be difficult to make out individual stars, and even more to identify them as belonging to a certain class of stars.
Does gravitational lensing magnify distant galaxies at distances up to 13 billion light years behind galaxy clusters?
Yes. Lensing magnifies the image of galaxies behind distant galaxy clusters but also greatly distorts the image.
Do galaxies at very large distances look distorted?
Yes, galaxies at very large distances can appear distorted due to gravitational lensing effects caused by the bending of light by massive objects. This distortion can elongate or warp the images of distant galaxies, altering their perceived shapes.
When scientists look at very distant galaxies through powerful telescopes they see the galaxies as they were millions or billions of year ago. Why is this?
The vast distances involved means that the light we see left those galaxies a long time ago.
When scientists look at very distant galaxies through powerful telescopes they see the galaxies as they were millions or billions of year ago Why is this?
The vast distances involved means that the light we see left those galaxies a long time ago.
The visible part of distant galaxies is the galaxies what?
The "nucleus".
Which kind of object is the best standard candle for measuring distances to extremely distant galaxies?
Probably type la supernova
Why are Cepheid variable so important for measuring long distances in the universe?
The perceived brightness of an object with known brightness can be used to gauge distances. Cepheid variables are known to have a brightness directly related to their period. Which means that if we know the period of the Cepheid variable, we know what its brightness is, and can use it to gauge the distance to the stellar group the Cepheid is part of.
