Hello,(adsbygoogle = window.adsbygoogle || []).push({});

I'm new here, but I have a question regarding Kirchoff's law (I think its Kirchoff's law, but I'm not sure). I'm looking at it now, and it says that E=M/Msub b. I know that the equation gives the emmittance of an object, but I don't know what emmissivity or emmittance is! Any help would be greatly appreciated.

Also, what's a P-Cygni profile for supernovae? I'm doing some research into supernova light curves, and from what I've found, Type II-P supernova have P-Cygni profiles, but the only sites I've found either too complex or too simple for what I need. Again, any help would be appreciated!

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Various astrophysics questions

**Physics Forums | Science Articles, Homework Help, Discussion**