Arecibo Observatory

UGC/AGC 7365     NGC 4262

Find the entry of this object in the ALFALFA archive, and use the images and links there to find the answers to these questions. As always, it is most important that you understand how to derive quantitative answers and their uncertainties.

  1. Check out the bar in the SDSS image. What is the morphological type of this galaxy?
  2. Compute the HI mass of the galaxy. Do you get the same answer as the value given in the ALFALFA database?
  3. Calculate the stellar mass of the galaxy. This won't be straightforward; explain your method and its uncertainties.
  4. What is the HI to stellar mass ratio of this galaxy?
  5. What is unusual about the appearance of the HI emission profile? Explain a reason why the profile might appear that way.

SDSS link

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Last updated Sat Oct 20 11:00:33 EDT 2007 by martha