Calculating distance of galaxy from Milkyway

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In summary, scientists use various methods such as the period-luminosity relationship, redshift measurements, and parallax measurements to calculate the distance of a galaxy from the Milky Way. The parallax method involves measuring the apparent shift in position of a nearby object, while redshift is determined by the shift in light towards the red end of the visible spectrum. Standard candles, such as Type Ia supernovae, are also used to calculate distances based on their known peak brightness. However, distance measurements are subject to errors and are limited to nearby galaxies with certain characteristics. Other techniques, such as gravitational lensing, may be used for more distant and fainter galaxies.
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A galaxy is observed to have a significant redshift in all of its spectral lines. The line normally seen at a wavelength of 327 nm is instead observed at 360 nm. How far is this galaxy from the milkyway

My approach


All I can calculate here is the red shift based on the formula

Z= observe wavelength- emitted/ emitted


Z= 360-327/327
=0.101

This has nothing to do with distance or does it?
 
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Hubble.
 

1. How do scientists calculate the distance of a galaxy from the Milky Way?

Scientists use a variety of methods to calculate the distance of a galaxy from the Milky Way. One common method is called the period-luminosity relationship, which uses the brightness and pulsation period of certain types of stars called Cepheid variables to determine the distance. Other methods include redshift measurements and parallax measurements.

2. What is redshift and how does it help calculate distance?

Redshift is a phenomenon where light from distant objects appears to have a longer wavelength, or is shifted towards the red end of the visible spectrum. This occurs because the object is moving away from us due to the expansion of the universe. By measuring the amount of redshift, scientists can calculate the distance of the galaxy from the Milky Way.

3. Why is the parallax method useful for calculating distances to galaxies?

The parallax method involves measuring the apparent shift in position of a nearby object when viewed from different points in space. By comparing the apparent position of a distant galaxy against the background of more distant objects, scientists can determine its distance. This method is useful for relatively nearby galaxies, as the parallax effect becomes smaller and harder to measure with increasing distance.

4. How do scientists use standard candles to calculate the distance of galaxies?

Standard candles are objects whose intrinsic brightness is known. By measuring the apparent brightness of a standard candle, scientists can calculate its distance based on the inverse square law of light. For example, Type Ia supernovae are often used as standard candles because they have a known peak brightness.

5. What are the limitations of using distance measurements to determine the distance of galaxies?

Distance measurements to galaxies are subject to various sources of error, such as uncertainties in the calibration of standard candles or errors in redshift measurements. Additionally, these methods are limited to galaxies that are relatively nearby and have a certain type of brightness or pulsation pattern. For more distant and fainter galaxies, other techniques such as gravitational lensing may be used to estimate the distance.

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