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Realm of the Nebulae - M57 vs M31

EL Obs 4

SPU-21 Fall 2014

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In this lab, we will measure two very different "nebulae": the Planetary Nebula, M57 (The Ring Nebula), and the Andromeda Nebula (as it was originally called), M31, which is of course our closest spiral galaxy. We'll observe M57 first since it is setting; then M31.

Fro M57, our goals for this Observation Report are to measure the B and V magnitudes of two parts of the Planetary Nebula (PN): its central hot white dwarf, which is the core of the star that ejected the PN, and the "ring" itself. Your Analysis of these observations will come in the Final Evelab Report in which you will use your measured B-V colors to estimate the blackbody temperature and luminosity of the WD and the Ring, and for the Ring to then deduce what type of radiation it really must be.

For M31, we shall measure the Bulge magnitudes (again in B and V) over a range of aperture sizes and in your later Analysis (Final Evelab Report) deduce from this the distribution of mass in the Bulge both within each aperture (a "cumulative" measurement) and in the annuli between each aperture (a "differential" measurement). The B-V colors in each annulus will allow you to estimate the approximate type of stars contributing to its light.

M57 Observations:

For this we can observe both M57 and our standard star in the same field.

Then for your exposures on M57 and your standard, take 2 exposures in each of the following filters for the times given: B (45 sec), V (30 sec) and R (30 sec). You will only use B and V for the analysis bur you can combine those images with the R band images for an RGB color image of M57 for your own pleasure (or to add as a nice figure in your Final Evelab Report). Enter in observations table (pdf or docx).

M31 Observations: