Observational Project with Skynet


For your second observing project for this course (10% of your course grade). You will take your own data using the Skynet telescopes to which you have access through the lab. You should analyze the images you take in some quantitative way, either using the Afterglow software other software described in the options below.

Here are some potential ideas, I’m happy to discuss other ideas you may have:

Take images of nearby galaxies in the B, V,  and R filters. Follow these steps  to make a combined RGB image (here G image = V filter image you take). What can you learn from the multicolor images, both in terms of comparing your galaxies to one another and from the way a single galaxy looks different in  the 3 filters? Here is a link to lists of galaxies you could choose from: https://en.wikipedia.org/wiki/List_of_galaxies Hint: Use the “Advanced Options” to take a single set of “interweaved” R, G, B images all with the same telescope

Take images of an open star cluster in two filters, say B and V.  Use the Measure the B and V magnitudes of the stars and create a color-magnitude diagram. How does it compare to the ones you used in lab? Here is a list of open star clusters: http://www.messier.seds.org/open.html  You will need to find a cluster from this list that is a) up in the sky now and b) an angular (apparent) size that is compatible with the field of view of the Skynet telescope you are using. Hint: Use the “Advanced Options” to take “interweaved” B and V images with the same telescope

Observe a variable star and make a light curve (magnitude versus time). You may find these resources of the American Association for Variable Star Observers useful. When choosing a source, consider its brightness (needs to be brighter than about 10th magnitude, i.e. magnitude < or equal to 10!) and its period of variability. You don’t need to observe one full period, necessarily, but you should acquire enough data over a long enough time period to be able to see changes.

Track an asteroid or comet over several nights. (Note that the tool in the links automatically uses your current location. You could reset it for the Southern Hemisphere locations of the PROMPT telescopes.) Make a diagram showing the path in the sky.

Take images of a few different star clusters or spiral galaxies. Use the angular size method to measure the distances to these objects. Compare with the accepted values that you can find online. You can use the list of clusters in #1 above or this list of spiral galaxies: https://en.wikipedia.org/wiki/List_of_spiral_galaxies


  1. Request data. Use Lab 1 to guide your exposure times, or consult with me. Note: You must make new observations for this project. It is ok to incorporate data you’ve already taken for the labs but you must supplement that with newly acquired data.
  2. Remember if your request does not begin executing within about 36 hours, you should cancel the request and try it again.
  3. Inspect your data. If the data are not high quality, repeat step 1. (See Lab 1 on Web Assign, or the Bb site under Labs -> Lab Tools -> Poor Quality Images if you’re not sure how to evaluate.)
  4. Reduce one of your Raw Images using the steps we discussed in our lab session and compare the results to the Reduced Images provided by Skynet by taking a ratio of the two images.
  5. Analyze your data.
  6. Write up report of at least 2 and no more than 3 pages of text (i.e., not including figures, tables, references). The report should include:
    • Description
    • Procedures, with the ratio image from step 4
    • Results, including
      • A sample of your Reduced Images (in the report, not as separate files)
      • Any other figures you generate, e.g. with Excel, from your measurements
      • The Exact name of the folder(s) where I can find your data using Afterglow.
      • Comparison of your result to known quantities
      • Discussion of sources of error
    • Reference list, with citations throughout. Include any websites you consulted. Use these sources critically.
  7. Upload your report to Bb.


  • Project choice due Thursday Nov. 4 11:59 PM
  • Project data check-in due Thursday Nov. 18 11:59 PM
  • Final project report due Thursday Dec. 16 11:59 PM



25% Timely & complete submission of all parts of the project

description/plan (5 pts)
check-in (10 pts)
final (10 pts)
20% point deduction for each day late

35% Level of effort and quality of final product.
This project is worth 10% of your course grade and should reflect approximately 4-6 hours of work.

Ideas (5 pts)
Generated a new question or chose and understood question posed in my examples

Effort (5 pts)
1: <2 hours
3: 3-4 hours
5: 4-6 hours

Execution (25 pts)
Gathered data
Included all necessary elements in the report

40% Extent to which final product relates to and extends understanding/interpretation of the course material. This will be gauged by the final product as well as the written summary and presentation.

Interpretation  (20 pts)
Demonstrated how the project is related to course material
Broadened scope of topic from what was covered in the course material

Accuracy (20 pts)
Interpretation of data is correct or plausible
Interpreted cited sources accurately