20110429

Astronomy quiz archive: Milky Way, cosmology

Astronomy 210 Quiz 6, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

Section 30676, version 1
Exam code: quiz06SoR3


Section 30676
Quiz 6 results (max score = 40):
0- 8.0 :
8.5-16.0 : ** [low = 11.0]
16.5-24.0 : *******
24.5-32.0 : **************** [mean = 27.7 +/- 6.5]
32.5-40.0 : ************ [high = 32.5]

Astronomy quiz archive: Milky Way, cosmology

Astronomy 210 Quiz 6, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

Section 30674, version 1
Exam code: quiz06n4Ke

Section 30674
Quiz 6 results (max score = 40):
0- 8.0 :
8.5-16.0 : ** [low = 11.0]
16.5-24.0 : *******
24.5-32.0 : **************** [mean = 27.7 +/- 6.5]
32.5-40.0 : ************ [high = 40.0]

20110427

Backwards-faded scaffolding laboratory/presentation: studying extrasolar planets

Our solar system, to scale. Eight planets, count 'em--four terrestrial ("Earth-like"), close to the sun; four jovian ("Jupiter-like"), much further away from the sun. If you think there should be nine planets, then I'm not sure which solar system you live in...

What about extrasolar planets, orbiting other stars? More and more of them are being discovered all the time--what generalizations can be made about these planets, compared to our solar system, and as a whole? (Video link: "Kepler Orrery (large & small systems).")

(This is the ninth 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.)

Let's consider two common methods of discovering extrasolar planets, taking into consideration that these methods do not actually "see" these extrasolar planets directly.

The first method involves observing an extrasolar planet either pass behind or in front of its star as it orbits the star, such that their combined brightness will fluctuate over time. (Video link: "Distant Planet Flaunts its Light.")

The second method involves observing an extrasolar planet pull on its star as it orbits the star, such that the star will be observed to "wobble" over time, much like the ball pulls back on the hammer thrower as they revolve. (Video link: "2010 Asian Games - Men's Hammer Throw Final.")

For this lab you will be accessing an enormous amount of data on these extrasolar planets, in order to find patterns and correlations.

One way to organize data is with a histogram, or "bar chart," where each type of category is tallied up, and their numbers are shown as different heights.

Another way to organize data is with a scatter plot, or "correlation diagram," where one characteristic is plotted versus another characteristic along horizontal and vertical axes.

So taking all the extrasolar planets from the data set, here shown superimposed on the "same" solar system... (Video link: "Kepler Exoplanet Candidates.")

...and plotting two properties versus each other on scatter graph, may show the resulting data points seeming to form a pattern, and thus indicating a correlation...

...or may instead seem randomly spread out, and in this case indicating no correlation between the two properties.

So these two types of graphs, bar charts and scatter plots, are very powerful and elegant ways to organize data and to find interesting results that may suggest underlying causes and effects among extrasolar planet properties.

Your personal experience with these tools may vary.

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?

20110417

Physics quiz archive: capacitors, circuits (2)

Physics 205B Quiz 5, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

Section 30882, version 1

Section 30882 results
Exam code: quiz05t4Uo
 0- 6 : 
7-12 : ** [low = 9]
13-18 : **
19-24 : * [mean = 20.3 +/- 7.1]
25-30 : *** [high = 27]

20110414

Astronomy quiz archive: stellar evolution

Astronomy 210 Quiz 5, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

Section 30676, version 1
Exam code: quiz05s0F7


Section 30676
Quiz 5 results (max score = 40):
0- 8.0 : ** [low = 2.0]
8.5-16.0 : ********
16.5-24.0 : *************** [mean = 21.1 +/- 7.7]
24.5-32.0 : *************
32.5-40.0 : *** [high = 36.0]

20110413

Astronomy quiz archive: stellar evolution

Astronomy 210 Quiz 5, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

Section 30674, version 1
Exam code: quiz05n4rA


Section 30674
Quiz 5 results (max score = 40):
0- 8.0 :
8.5-16.0 : ******* [low = 7.5]
16.5-24.0 : ********** [mean = 22.8 +/- 7.6]
24.5-32.0 : *****************
32.5-40.0 : *** [high = 40.0]

20110406

Overheard: "galaxy scratchers"

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

110323-1220796
http://www.flickr.com/photos/waiferx/5561971349/
Originally uploaded by the Waifer X

(Overheard while students are being tested on categorizing different galaxy types on the GalaxyZoo project used in a backwards folded scaffolding laboratory activity.)

Instructor: "So how are you doing on the 'scratchers' part of the lab?"

(Beat.)

Student 1: "The what?"

(Beat.)

Student 2: (Laughs.)

20110401

Physics quiz archive: capacitors, circuits

Physics 205B Quiz 4, Spring Semester 2011
Cuesta College, San Luis Obispo, CA

Section 30882, version 1

Section 30882 results
Exam code: quiz04t4c0
 0- 6 : 
7-12 : *** [low = 9]
13-18 : *** [mean = 16.1 +/- 5.1]
19-24 : ** [high = 24]
25-30 :