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Tagged with distances luminosity
5 questions
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Is luminosity distance related to both heliocentric redshift and CMB restframe redshift？
The luminosity distance
$$d_l=(1+z)r(z)\ ,$$
where $r(z)$ is given by $$r(z)=cH^{-1}_0\int_{0}^{z}\frac{dz'}{E(z')}\ .$$
When I use the SNe dataset "Pantheon", I find there are two redshifts:...
- 21
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How to calculate the distance to galaxies with standard candles?
I was wondering how the distance in Mpc could be calculated between Earth and a galaxy using the luminosity provided? Do not be shy to use all math necessary :)
Clarification:
Luminosity is inversely ...
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Problem about finding distance with magnitude given
A star in Pleiades cluster has apparent magnitude of +12 ($m_{star} = +12$) determine it's distance from the sun? (We know the Sun properties such apparent and absolute magnitudes, distance from earth,...
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How to find a Cepheid's pulsation period using its graph?
Basically, I've been seeing these graphs that say: Cepheid Period-Luminosity Relation and the Period axis is supposed to be "logarithmic";
How does this graph work? Since the luminosity of a star ...
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What would be the apparent magnitude of Betelgeuse if it were as close to Earth as Sirius?
How large and bright would Betelgeuse appear if it were as close to Earth as Sirius, before and after it goes supernova?
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