Luminosity, Flux, Time: What Do They Mean?

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The discussion revolves around the equations L=A[sig]T4 and f=L/A=[sig]T4, questioning the role of time in these formulas. Participants explore how to calculate the magnitude a telescope can reach when integrating over different time periods, such as comparing 10 seconds to 1 hour. The concept of spectral resolution is also examined, specifically what a spectral resolution of 5 signifies. Additionally, the conversation touches on the energy received by a telescope from stars of varying magnitudes, emphasizing the importance of understanding these relationships in astronomy. Overall, the thread seeks clarity on the interplay between luminosity, flux, time, and their implications in observational astronomy.
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L=A[sig]T4
f=L/A=[sig]T4
Where does time come into these equations?

If one telescope of a known diameter can reach a certain magnitude, it is easy to find what magnitude a different telescope of known magnitude can reach. But if a telescope integrating over 10s can reach a certain magnitude, how can we determine what magnitude the same telescope will reach integrating over 1hr?

Also, what does it mean for something to have a spectral resolution of 5?
 
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Where does time come into these equations?
What are the units of [sig]?
But if a telescope integrating over 10s can reach a certain magnitude, how can we determine what magnitude the same telescope will reach integrating over 1hr?
Assuming you're still way above sky noise, presumably.
If one star has a magnitude of 5, and another 10, what is the ratio of the energy received, in unit time, by the same telescope?
How many seconds are there in an hour?
 
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