20110421

Backwards faded scaffolding laboratory/presentation: moons & motions

Maybe it's a good thing that Earth only has one moon...

(This is the eighth Astronomy 210L laboratory at Cuesta College, San Luis Obispo, CA. This course is a one-semester, optional adjunct laboratory to the Astronomy 210 introductory astronomy lecture, taken primarily by students to satisfy their general education science transfer requirement.)

Galileo discovered four of Jupiter's moons, and their motion around Jupiter, while it didn't necessarily disprove geocentrism and prove heliocentrism, did manage to resolve an objection to a moving Earth--if the moon revolves around Earth, and Earth did move, then shouldn't it leave the moon behind? Note that the orbits of these moons are seen edge-on, so we see lots of eclipsing here as these moons either pass in front of or behind Jupiter.

So the first type of eclipse is a transit, where a smaller object (in this case, Io) passes in front of a larger object (Jupiter). Because the sun is actually off to the right in this telescope view, Io's shadow on Jupiter is to the left of Io. Remember for a transit, "a small thing travels across a larger thing."

The second type of eclipse is an occultation ("hidden," similar to a "cult"), where a larger object (in this case, the moon) passes in front of a smaller object (Saturn). So for an occultation, "a small object hides behind a larger thing."

Today, instead of using the motion of Jupiter's moons to adjust clocks, which are now much more accurate, the timing of transits and occultations are timed in order to refine information and models of astronomical positions and sizes.

Today you'll investigate not only the motion of the moon and Jupiter's moons on NASA's Solar System Simulator (space.jpl.nasa.gov), but also gather data on the orbital periods, transits, and occultations of other objects as well.

Transit, or occultation?

Transit, or occultation?

2 comments:

  1. Astronomy 210L, Spring Semester 2011
    Cuesta College, San Luis Obispo, CA

    Online post-lab assignment 7

    Discuss the most interesting aspect of this lab, and explain why this was personally interesting for you.

    The following are a sampling of the student responses to this question, verbatim and unedited.

    "Seeing how the moons around jupiter orbit at an extremely high rate of speed."

    "Checking out the Planets and their orbits"

    "how moons revolve around planets."

    "measuring the distances of jupiters moon"

    "learning about the moons of Jupiter."

    "Seeing moons of other planets"

    "Being able to see Jupiter's moons move across Jupiter was neat."

    "Discovering how fast some of Jupiter's moons travel."

    "Looking at various moons orbits"

    "Seeing how long it takes the moon to orbit the Earth."

    "The most interesting part of this lab was the website; the design was simple and well put together, and I liked being able to easily see any planet, moon, or spacecraft I wanted and their respective orbits."

    "To see how the moons travel at different speeds depending on how far away from the planet."

    "I thought it was interesting to figure out how long it took for an object to go around one whole time"

    "learning how to accurately understand moon orbits"

    "discovering how to track moon transits"

    "Everything was interesting"

    "Learning about moons"

    "I thought seeing how fast or slow other planets moons orbits their planet was interesting."

    "The most interesting part of this lab was to see that each moon orbited the planets at different speeds. Some only took 2 days get around the planet and others can take months."

    "The solar system simulator"

    "I thought the NASA website was pretty cool..technology these days."

    "For me, the most interesting aspect of the lab was learning that every body moves at a different rate in a different path in our solar system."

    "it was interesting to learn how much moon orbits can vary in time and distance."

    "i really liked talking about Jupiter's moons"

    "seeing how the moons orbit was very interesting"

    "The most interesting aspect of this class was looking at the planets orbiting at different times in the month."

    "Following the moons path"

    "Being able to see the solar system from other view points than earth"

    "It was intersting to where the plantes over a certain time."

    "I learned what the difference between occultation and transit. It it intersting because i didnt know what they were before."

    "How you could find out all that information in Juipter."

    "It was neat-o. Moons are cool."

    "The most interesting thing was researching on the nasa website."

    "tracking the orbits of moons around jupiter"

    "I liked measuring the distance between Jupiter and its' moons."

    "using the website to determine how long it takes certain moons to revolve around planets"

    "I liked finding the data because it was sort of easy."

    "Seeing the change in location of the planets moon/moons."

    "would be seeing the moon changing"

    "I thought using the Solar System Simulator website was interesting."

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  2. Astronomy 210L, Spring Semester 2011
    Cuesta College, San Luis Obispo, CA

    Online post-lab assignment 7

    Discuss the most confusing aspect of this lab, and explain why this was personally confusing for you.

    The following are a sampling of the student responses to this question, verbatim and unedited.

    "Nothing was too tough, other than formulating a research question that was detailed and unique from the other groups."

    "formulating the question, lab question #5"

    "Some of the moon's movements seemed weird. They didn't always move the way you'd expect."

    "How long Jupiter's moons take to orbit."

    "Trying to find the exact number of days a moon does a full orbit around a planet"

    "finding the distances"

    "Everything was clear"

    "recording transit time to the exact minute"

    "deciding on specific time to use at correlation points"

    "Nothing was confusing"

    "lab was pretty clear"

    "How to calculate the orbit of the planets"

    "I wasn't really confused about anything except for Jupiters moon orbit."

    "As always, i have trouble forming my own question at the end."

    "not a damn thang"

    "not confusing"

    "I did not like having to form a research question"

    "The most confusing part was trying to figure out a research question."

    "No confusion"

    "Coming up with a research question was pretty difficult this time"

    "understanding when something was behind or in front of another object"

    "Find the data for the research question but after we knew what program to use it was easy."

    "Some of the questions of the lab were confusing. After rereading them they made sense."

    "The website we had to go to."

    "It wasnt that confusing."

    "I didn't think anything of this lab was confusing."

    "Being able to determine if something is occulating or transiting based on the website we used"

    "Once again, the research question."

    "pretty straight forward lab"

    "Coming up with the research because it's just tricky man."

    "I find it difficult to get the hang of some of the web sites. I Also found I hard to exactly know when the moons were behind the planet."

    "The research question is always the most tricky."

    ReplyDelete