Attached.

Galaxy Zoo

Big Idea: The countless and varied galaxies observed throughout the Universe have
characteristics that can be classified.
Goal: Students will conduct a structured series of scaffolded scientific inquiries about the nature
of observed galaxies using the Internet sites prescribed, particularly the Sloan Digital Sky Survey
via Galaxy Zoo
Computer Setup:
Access http://www.galaxyzoo.org/
Phase I: Tutorial: After going to www.galaxyzoo.org, select Begin Classifying (yellow
button on the left). You will be completing the tables below as you go along. You can either use
text highlighting in your word processor to highlight your answers, or place an X in front of your
selection. If it doesn’t ask a questions, just skip it. Clicking the “Invert” icon inverts the image to
be white background instead of black background, which might help you to identify features.
For each question, click on the blue Examples button to see examples to help you decide. You
can click on the individual examples to enlarge the image to see better. Record your data for each
image in the tables below (one table per image). You can either underline your answer, highlight
it in a different color or put an X next to it. You will classify at least 20 images. After you have
classified a few, it will prompt you to sign in to receive credit for your work. This is optional.
1) Is the galaxy simply smooth and rounded, with no sign of a disk?
A) If you answer “Features/Disk,” it will then ask you the following questions. Mark N/A on your
table if you are not asked these questions.
i) Could this be a disk viewed edge-on?
(1) If you answer yes, it will then ask you the following question. Mark N/A on your table if
you are not asked these questions.
(a) Does the galaxy have a bulge at its centre? If so, what shape?
ii) Is there any sign of a bar feature through the centre of the galaxy?
iii) Is there any sign of a spiral arm pattern?
iv) How tightly wound do the spirals appear?
v) How many spiral arms are there?
vi) How prominent is the central bulge, compared with the rest of the galaxy?
B) If you answer “Smooth,” it will then ask you the following questions. Mark N/A on your table if
you are not asked these questions.
i) How rounded is it?
2) Is the galaxy currently merging or is there any sign of tidal debris?

3) Do you see any of these odd features in the image? Note: after selecting as many as apply,
click “Done.”
1

4) The last question on the website is whether or not you want to discuss the image with other
users. This is not part of the lab, but if you see something interesting and choose to
participate in the site’s discussion area, that’s totally fine.
Image #1
Ring
Round

Edge-on

In between

Not edge-on

Cigar shape

N/A

Smooth
Features/Disk

Round

Merging

Lens or Arc

Boxy

Tidal debris

Irregular

No bulge

Both

Other...