0
votes
1answer
18 views

How does intensity differ from apparent luminosity in the context of photometry?

Context: photometry in astronomy. Background: The total luminosity $L$ of a star is the energy that radiates in all spatial directions in all wavelengths and is given by the following formula, where ...
0
votes
2answers
82 views

Quick question on astronomical units

I'm trying to solve for $\frac{M*}{M_0}$ and $p''$ using these two equations: Here is the lecturer's working, I worked it out several times and I got a different answer! Surely when you use ...
5
votes
2answers
98 views

How many watts of light do instruments in modern telescopes need?

I just calculated that if the European extremely large telescope(978 m^2 area) would be pointed at the Andromeda galaxy once it is built, it will only get mere 1.2*10^-6 Watts of power from Andromeda. ...
1
vote
1answer
1k views

Find temperature of surface (Blackbody Radiation) [closed]

An astronomer is trying to estimate the surface temperature of a star with a radius of $5 \times 10^8\ m$ by modeling it as an ideal blackbody. The astronomer has measured the intensity of ...
1
vote
2answers
174 views

What is the Schechter luminosity function's domain of support?

I'm trying to fit a Schechter luminosity function to some data points, but it's not clear from this definition what the domain of support of the PDF should be. I'm familiar with the standard Pareto ...
6
votes
3answers
480 views

Binary stars' apparent magnitude

If you plot the apparent magnitude of a binary system (so you are unable to see 2 distinct stars) against time, it gives a repeating 'M' effect. (from http://accessscience.com/) Assuming one star ...