20120831

Astronomy current events question: 'monster' sized star origins

Astronomy 210L, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Robert Massey, "Astronomers Crack Mystery of the 'Monster Stars,'" August 7, 2012
http://www.ras.org.uk/news-and-press/219-news-2012/2158-astronomers-crack-mystery-of-the-monster-starsq
University of Bonn researchers have proposed that monster-sized stars in the Large Magellanic Cloud were created by:
(A) nearby supernova explosions.
(B) merging stars in binary systems.
(C) production of superheavy elements.
(D) gravitational perturbations from supermassive black holes.
(E) decaying dark matter.

Correct answer: (B)

Student responses
Sections 70178, 70186, 70200
(A) : 8 students
(B) : 49 students
(C) : 1 student
(D) : 4 students
(E) : 2 students

Astronomy current events question: Curiosity rover power source

Astronomy 210L, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Martin LaMonica, "Nuclear Generator Powers Curiosity Mars Mission," August 7, 2012
http://www.technologyreview.com/view/428751/nuclear-generator-powers-curiosity-mars-mission/
The NASA Mars Science Laboratory Curiosity rover on Mars is powered by __________ to provide heat and electricity.
(A) byproducts from onboard photosynthetic bacteria.
(B) chemicals that react with water vapor.
(C) regenerative fuel cells.
(D) a nuclear generator.
(E) solar panels.

Correct answer: (D)

Student responses
Sections 70178, 70186, 70200
(A) : 0 students
(B) : 2 students
(C) : 4 students
(D) : 36 students
(E) : 22 students

Astronomy current events question: Iapetus sturzstroms

Astronomy 210L, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Monica Young, "The Curious Avalanches of Iapetus," July 31, 2012
http://www.skyandtelescope.com/news/The-Curious-Avalanches-of-Iapetus-164470306.html
A Washington University in St. Louis, Missouri graduate student has analyzed high-resolution images of sturzstroms on Saturn's moon, Iapetus, which are:
(A) clouds that produce thunder, but no lightning.
(B) planetary ring disruptions.
(C) thick underground deposits of ice.
(D) large landslides of flowing debris.
(E) cyclonic ice storms.

Correct answer: (D)

Student responses
Sections 70178, 70186, 70200
(A) : 3 students
(B) : 2 students
(C) : 8 students
(D) : 41 students
(E) : 7 students

20120829

Online reading assignment: motion

Physics 205A, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters (Giambattista/Richardson/Richardson, Physics, 2/e, Chs. 2.2-2.5) and previewing a presentation on constant acceleration motion.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"I'm learning more about the formulas and enjoy the connections with higher level calculus. The graphs are pretty."

"Honestly, I am having a hard time finding something interesting. This is very dry, unfortunately."

"I found your 'learn it, know it, live it' motto interesting and amusing!"
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"Some of the equations I couldn't wrap my head around. I need them explained to me in a different way than the book explains them."

"Nothing was too confusing in the reading mainly because I have taken calculus and a physics class in high school so the material is very familiar."

"The formulas were a little confusing since I never took calculus."

"The chain of pain is confusing."
Briefly describe the difference(s) between a chord slope and a tangent slope on a graph.
"A chord slope passes through a curve at two points and is the average slope between them. A tangent slope runs along a point on a curve, but does not pass through it and is the slope of the curve at that point."

"Honestly, I don't remember reading about those and couldn't tell you what the difference is."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"How much calculus must we know for this course?"

"I could really really use your help on this reading material in class. It's way too deep for me to teach myself and just have it brushed over in class."

"I'm glad you simplify all this stuff in class. I would be so lost otherwise."

"Are the surveys for Monday's lecture due at 12:00 AM on Sunday night? Because I got an error message at 11:00 PM last Sunday."

20120828

Online reading assignment: motions and cycles

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters (Seeds/Backman, Perspectives on Astronomy, 1/e, Chs. 2-2, 2-3, 2-4) and previewing presentations on Earth's rotation/precession/revolution/tilt, and the moon's motions and cycles.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"It was odd to know that the axis wobbles and the northern star changes."

"Seasons are caused by changes in the amount of the sun's energy obtained by Earth's northern/southern hemispheres at different times of the year. I found this interesting because I was under the impression that Earth was either farther/closer to the sun at different times of the year causing the seasons."

"I never knew when the sun was lower it was winter, and when it was raised high in the sky it meant it was summertime."

"In Australia you can see constellations that are invisible to North America. But they never see the Big Dipper... I had never really thought about if different things were seen in the night sky in different places on Earth.."

"Although we can't see them during the daytime, there are still stars during the daytime. I guess it caught my attention because I never took into consideration what happened to the stars during the daytime."

"The fact that the sun lines up directly with particular [zodiac] constellations."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"Having a hard time understanding the difference between all the phases of the moon. Especially between the waxing and waning phases of the moon."

"I thought that the seasons were caused by the distance from Earth to the sun."

"The zodiac and the way the stars lined up with the sun confused me. I just don't really get how that affects someone's future, or personality, or whatever."

"Knowing whether stars or rising or setting in a time-lapse photo...that is confusing and I look forward to finding out how to tell."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Do you believe in astrology?"

"What causes a blue moon to occur once a year?"

"What will be the most useful study tool for this class?"

"I was unable to purchase the starwheel/textbook because the bookstore was sold out... Is there another store close by that we can purchase the textbook/starwheel from?"

20120827

Online reading assignment: speed and velocity

Physics 205A, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on the reading textbook chapters (Giambattista/Richardson/Richardson, Physics, 2/e, Chs. Chs. 2.1-2.2) and previewing a presentation on displacement, distance traveled, and average/instantaneous speed/velocity.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"Differentiating between displacement and distance."

"Displacement of certain things can be so much less than the actual distance traveled."

"Greek letter delta actually means 'the change in...'"

"I've learned all this before. Nothing really interesting here."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"Most of it was confusing to me."

"Nothing confusing in these readings. I've taken physics before."

"Instantaneous velocity versus average velocity kind of confusing because of the limit formula for the instantaneous velocity."
Briefly describe how you would walk along a straight, level road such that your distance traveled would be longer than your displacement.
"You could walk forward for 10 feet and then backwards for 5 feet. The distance traveled is 15 feet but the displacement is only 5 feet."

"One step forward, two steps back. Story of my life."

"You could serpentine across the road. Your distance travled would be longer than your displacement."
Briefly describe the difference between an odometer and a speedometer.
"Mileage vs. speed."

"An odometer measures distance traveled, and a speedometer measures your average speed, or distance traveled divided by a short time interval."

"Odometers tracks distances traveled, while speedometers track the instantaneous speed."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Will negative velocities always correspond to traveling west, and does this also apply to traveling south?"

"Will we need to memorize all of the equations we get in the book for tests?"

"By the time class starts Monday, I will have gone to the library to borrow the book."

"Your beard/mustache is quite impressive."

20120826

Astronomy in-class activity: first-day student expectations, questions

Astronomy 210 In-class activity 1, fall semester 2012
Cuesta College, San Luis Obispo, CA

120826-interesting
http://www.flickr.com/photos/waiferx/7869717832/
Originally uploaded by Waifer X

Wordle.net tag cloud for potentially interesting astronomy topics, generated by students on the first day of class (www.wordle.net/show/wrdl/5604344/Untitled).


120826-confusing
http://www.flickr.com/photos/waiferx/7869718370/
Originally uploaded by Waifer X

Wordle.net tag cloud for potentially confusing astronomy topics, generated by students on the first day of class (www.wordle.net/show/wrdl/5604364/Untitled).


On the first day of class, students find their assigned groups of three to four students, and work cooperatively on an in-class activity worksheet to discuss concepts that will potentially be interesting or confusing to them later in the semester. Students are also encouraged to write down a comment or a question for the instructor to go over during the whole-class discussion, after the in-class activity worksheets are turned in.

[Responses have been edited to consolidate common related subjects.]

Discuss in your group astronomy-related concepts you expect to be interesting or confusing later in this course. Use one word or short phrases (e.g., "Pluto," "black holes," "beginning of time") for each concept.

List at least three astronomy-related concepts you expect to be interesting.

Student responses
Sections 70158, 70160
zodiac, galaxies, voids, blackholes
constellations, solarsystems, galaxies, gravity
blackholes, darkmatter, aliens
zodiac, constellations, planets
blackholes, aliens, planets
stars, constellations, asteroids, meteors, meteorites, magneticfields
bigbang, stars, size
planets, constellations, lightyears
neutronstars, blackholes, stars
blackholes, galaxies, meteors
blackholes, StephenHawking, darkmatter, CarlSagan, neutrinos, Higgsboson
galaxies, starcharts, time
blackholes, asteroidbelt, darkmatter
universe, navigation, planets
stars, galaxies, lookbacktime, lightyears
orbits, meteorshowers, solareclipse
light, planets, unknown
solarsystem, solarflares, constellations
infinity, time, meteors, comets, darkenergy, darkmatter
constellations, tides, stargazing
galaxies, stars, aliens, blackholes
tides, MilkyWay, bigbang
blackholes, greenflash, constellations, northernlights, asteroids
blackholes, wormholes, universe, aliens

List at least three astronomy-related concepts you expect to be confusing.

Student responses
Sections 70158, 70160
blackholes, planets, constellations
physics, timetravel, stringtheory
aliens, starcharts, blackholes
blackholes, physics, universe
solarsystem, orbits, physics
lightyears, math, blackholes, bigbang
physics, expansion, time
blackholes, size, gravity, orbit
size, aliens, physics
light, sun, stars, galaxies
physics, light, dwarfplanets, Pluto, CarlSagan
elementaryparticles, aliens, blackholes
bigbang, aliens, stars
lightyears, distances, space, time
light, size, relevance
blackholes, darkmatter, time, cycles, timezones, Pluto
solarflares, starcharts, planets
blackholes, solareclipse, constellations
stars, blackholes, distances, lightyears
blackholes, gravity, starcharts
size, bigbang, satellites, orbits, 2012
light, math, composition
blackholes, constellations, galaxies
universe, solareclipse, bigbang

Each week after class you will receive credit for asking a question, or making a comment that the instructor might respond to at the start of the following class (while your identity is kept anonymous). Ask at least one question, or make a comment that you would like the instructor to respond to at the end of this in-class activity.

Student responses
Sections 70158, 70160
"Will the sun explode soon?"

"How do astronomers map out galaxies that far away? How far is the Death Star from Earth? Do Wookies exist?"

"What is dark matter?"

"Will we learn about the Greek constellations or how do you feel about it?"

"How is astronomy applicable to my everyday life?"

"What is the big bang theory?"

"Where does the name 'P-dog' derive from?"

"Why do you like astronomy?"

"What is the difference between nuclear fusion and nuclear fission?"

"How should we prepare for tests?"

"Will we be discussion the Curiosity rover mission? Also it is interesting to note that both Mars rovers contain metal from the fallen World Trade Centers. "

"What makes the planets rotate in the solar system? When is the sun expected to die?"

"How is astronomy related to astrology?"

"Have you ever seen the movie 'Event Horizon?'"

"Are we going stargazing?"

"What makes a planet versus what makes a star?"

"Are we going to stargaze? Will we use the giant telescope? Why 'P-dog' and not 'P-dawg?'"

"Do our questions need to be astronomy related?"

"How do you measure the space between matter?"

"Do you believe in aliens?"

"Looking into the sky is like looking into the past."

"How did you get the name 'P-dog?' Why 'dog' instead of 'dog?' Conditions a green flash requires to happen."

"How far can our modern-day best telescope see into space?"
Previous posts:

Astronomy in-class activity: astronomy in the marketplace tags

Astronomy 210 In-class activity 1, fall semester 2012
Cuesta College, San Luis Obispo, CA

120826-carwordle-1
http://www.flickr.com/photos/waiferx/7868471710/
Originally uploaded by Waifer X

Wordle.net tag cloud for astronomy-related car brand names, generated by responses from Astronomy 210 students at Cuesta College, San Luis Obispo, CA (www.wordle.net/show/wrdl/5603765/Untitled).


120826-foodwordle-1
http://www.flickr.com/photos/waiferx/7868472104/
Originally uploaded by Waifer X

Wordle.net tag cloud for astronomy-related food brand names available in a supermarket, generated by responses from Astronomy 210 students at Cuesta College, San Luis Obispo, CA (www.wordle.net/show/wrdl/5603840/Untitled).


120826-nonfoodwordle-1
http://www.flickr.com/photos/waiferx/7868472554/
Originally uploaded by Waifer X

Wordle.net tag cloud for astronomy-related non-food brand names available in a supermarket, generated by responses from Astronomy 210 students at Cuesta College, San Luis Obispo, CA (www.wordle.net/show/wrdl/5603867/Untitled).


Students find their assigned groups of three to four students, and work cooperatively on an in-class activity worksheet to discuss car brand names, and food and non-food brand names found in supermarkets (adapted from D. Schatz, "Why Should We Care About Exploding Stars?" Universe in the Classroom, no. 8, Spring 1987 (http://www.astrosociety.org/education/publications/tnl/08/stars2.html).

There are many astronomy-related brand names. Consider car brand names (old and new); and brand names for food and non-food items that are typically found in the supermarket. Do not consider titles of TV shows, movies, or books.

List at least three astronomy-related car brand names.

Student responses
Sections 70158, 70160
?, ?, ?
Saturn, Galaxy, Comet, Astro, Mercury
Saturn, Taurus, Eclipse, Navigator, Mercury
Saturn, Astro, Mercury, Eclipse
Saturn, Infiniti, Mercury, Galaxy, Explorer
Saturn, Taurus, Mercury, Nova, Solaris
Saturn, Mercury, Eclipse, Astro, Taurus
Saturn, Mercury, Infiniti, Eclipse, Soul
Saturn, Subaru, Eclipse, Mercury, Astro
Mercury, Saturn, Subaru, Eclipse, Astro
Saturn, Mercury, Taurus, Soul, Eclipse
Eclipse, Saturn, Subaru, Mercury, Astro
Galaxy, Fusion, Mercury, Firebird, Volt, Skyline
Galaxy, Saturn, Mercury, Astro, Eclipse
Eclipse, Mercury, Saturn, Equinox, Taurus
Eclipse, Saturn, Taurus, Mercury
Mercury, Saturn, Atom, Eclipse, Taurus
Astro, Mercury, Saturn, Solaris, Nova
Mercury, Saturn, Sirius, Taurus
Saturn, Mercury, Taurus, RangeRover
Mercury, Saturn
Mercury, Saturn, Taurus, Comet, Galaxy
Nova, Eclipse, Saturn, Taurus, Mercury
Galaxy, Nova, Mercury, Saturn, Comet

List at least three astronomy-related food brand names typically found in the supermarket.

Student responses
Sections 70158, 70160
MilkyWay, Marsbars, ChickenandStars, Sparks
BlueMoon, CapriSun, Starburst, Sunkist, MilkyWay
BlueMoon, MilkyWay, Marsbars, MoonPies, Starburst, SunChips
MilkyWay, Starburst, Marsbars, Sundrop, Sunkist
MilkyWay, SunnyD, Sunkist, Starburst, Sunchips
Moonpies, Starburst, Marsbars, MilkyWay, CelestialSeasonings, Starbucks
Marsbars, MilkyWay, Sunkist, SunnyD, Starburst
Starburst, LunaBar, MilkyWay, Sunchips, Eclipse
Marsbars, MilkyWay, LunaBar, Sunkist, Starbucks
MilkyWay, Mars, MoonPie, Starburst, Sunchips
MoonPies, MilkyWay, Marsbars, Orbit, SunnyD
Eclipse, Starbucks, Marsbars, LunaBar, MilkyWay
MilkyWay, Cometpeanutbutter, Fireballs, MoonPie
MilkyWay, blueberries, Marsbars, FigNewtons
sundriedtomatoes, SunMaid, Marsbars, MilkyWay, Starburst, SunChips
Marsbars, MilkyWay, Orbit, Cosmic, MoonPies
MilkyWay, SunChips, Marsbars, LunaBar, Starburst
MilkyWay, Starburst, MoonPie, BlueMoon, SunnyD, Orbit
MilkyWay, Orbit, StarFarms, SunChips, Starburst, sunflowerseeds, BlueMoon
BlueMoon, Starburst, MilkyWay, Marsbars
MilkyWay, SunnyD, Orbit
MilkyWay, AngryBirdsinSpace, Marsbars, starfruit, Starburst
MilkyWay, Marsbars, Starburst, Orbit, Corona, SunnyD
MilkyWay, Marsbars, LuckyCharmsshootingstars, Starburst, starfruit

List at least three astronomy-related non-food brand names typically found in the supermarket.

Student responses
Sections 70158, 70160
Comet
Comet, Orbit, Clips
BuzzLightyear, Comet, Venus, FiveStar, sunblock
SamsungGalaxy, FamousStarsandStripes, Venus, BlueMoon, solarpanel
Comet, Orbit, Eclipse, LashBlast, BareMinerals
Venus, Comet, Dawn, Tide, Solarcain, sunblock
Comet, MercuryRising, BlueMoon, Venus, Omega
Venus, Comet, Sunkist, BlueMoon, Crest
BlueMoon, LunaVineyards, Solace, Comet, Sun, Tide
BlueMoon, Sunkist, Orbit, Rockstar, Comet
LightYear, Venus, Comet, BlueMoon
BlueMoon, Comet, Dawn, Firestone, Solace, Tide
Comet, Skyy, Cosmopolitan, TequilaSunrise, Sunkist
BlueMoon, Venus, Orbit, Eclipse
BlueMoon, SunnyD, Venus, Orbit, Dawn, Comet
Comet, Venus
BlueMoon, Comet, Tide, Dawn, Venus
Venus, Comet
Venus, lightbulbs, Comet
GalaxyTheater, SamsungGalaxy, DarkSideoftheMoon
Orbit
RockStar, Corona, BlueMoon, CapriSun
Venus, Comet, CoinStar, Sun, Tide
Constellation, Sunkist, Comet, Dawn, Solace

Previous posts:

Tweet: Drake equation


Astronomy quiz question: starwheels

2012-08-22_21-25-06_833
http://www.flickr.com/photos/waiferx/7854663120/
Originally uploaded by Waifer X

Three principal types of starwheel (planisphere) questions. Photo by Cuesta College Physical Sciences Division instructor Dr. Patrick M. Len.

20120825

Student scribble: boiling point boat

2012-08-22_21-24-10_934
http://www.flickr.com/photos/waiferx/7854657942/
Originally uploaded by Waifer X

"The boiling point is when the vapor pressure equals..." Photo by Cuesta College Physical Sciences Division instructor Dr. Patrick M. Len.

20120824

Cuesta College North County campus telescope shelter

2012-08-08_14-14-21_485
http://www.flickr.com/photos/waiferx/7854649760/
Originally uploaded by Waifer X

North County campus telescope shelter, under construction. Funding provided by the Cuesta College Foundation. Photo by Physical Sciences Division instructor Dr. Patrick M. Len.

FCI pre-test comparison: Cuesta College versus UC-Davis (fall semester 2012)

Students at both Cuesta College (San Luis Obispo, CA) and the University of California at Davis were administered the 30-question Force Concept Inventory (Doug Hestenes, et al.) during the first week of instruction.

Cuesta College
Physics 205A
Fall semester 2012    
UC-Davis
Physics 7B
Summer session II 2002
N70 students*76 students*
low 0 2
mean     9.6 +/- 5.0 9.1 +/- 4.3
high2627

*Excludes students with negative informed consent forms (*.pdf)

Student's t-test of the null hypothesis results in p = 0.46 (t = 0.748, sdev = 4.63, degrees of freedom = 144), thus there is no significant difference between Cuesta College and UC-Davis FCI pre-test scores.

Later this semester (fall 2012), a comparison will be made between Cuesta College and UC-Davis FCI post-tests, along with their pre- to post-test gains.

D. Hestenes, M. Wells, and G. Swackhamer, Arizona State University, "Force Concept Inventory," Phys. Teach. 30, 141-158 (1992).
Development of the FCI, a 30-question survey of basic Newtonian mechanics concepts.

Previous FCI results:

20120822

Online reading assignment: course policy, units

Physics 205A, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on the course policy/syllabus, and on introductory textbook chapters (Giambattista/Richardson/Richardson, Physics, 2/e, Chs. 1.4-1.6) on SI units and dimensional analysis.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or syllabus flashcard questions, and explain why this was personally interesting for you.
"The three lowest quiz scores will be dropped."

"No + or - in grading scale."

"The final was worth 100 point max. Usually finals are worth more points."

"One could earn less than 90% in the class and have an A."

"It takes three skipped labs in order to fail the class."

"If someone misses an exam with an acceptable excuse they will be given a replacement grade using the mean of the class on that grade."
(The above comment is a misinterpretation of the course policy on a replacement grade for an excused missed exam. A replacement grade is generated relative to the class mean as calculated by the student's score on the other exams relative to the class mean.)
"In section 1.6 it says not to add 3 meters to 2 kilograms. Why would anybody try to do that?"

"A lot of this is review from the chemistry courses that I just completed but I decided to still take the time and read through the assignment carefully as I may have got sloppy with my sig figs!"

"The metric system we use today was abbreviated using a French name. I mean, why was it French?"

"NASA destroyed a $125 million spacecraft due to a difference in the units used. I would have thought that they would double check that the units are both metric before moving on."

"Writing down the units of the quantity when working out an equation, this helps cancel out units and also helps with figuring out the correct unit at the end of the equation."
Describe something you found confusing from the assigned textbook reading or syllabus flashcard questions, and explain why this was personally confusing for you.
"On the first question of the flashcard questions, I did not understand what the question was saying because the way I am reading it, there are multiple answers."

"If homework is not graded how do I know I got the answer right?"

"Are there answers to the practice problems that follow the examples?"

"Where are the answers to the multiple choice questions and other questions assigned?"

"Are laptops acceptable if you're using them to take notes?"

"I found the dimensional analysis to be very confusing to me, I think mainly because i haven't done something like that in a long time."

"I found it odd that in the textbook, I could not find the common conversion factors. The book said that they would be on the inside of the front cover, but I could not find them."

"As we know .1 is one tenth and .01 is one hundredth, shouldn't that 0 be important because it shows that it is smaller by another factor of 10? I know that there is 1 sig. fig. in both, but understanding I just feel, I have a hard time grasping it."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"As I was reading over the extra credit section in the syllabus I couldn't find a description of what the extra credit would look like just that there would be some rounding. Is the rounding the extent of the extra credit or are there assignments as well?"

"Maybe a bit of review on conversions and a few practice problems."

"When posting homework assignments, write the date they are due instead of just 'before next lecture.'"

"I don't have anything to ask or comment on. :/"

"Why are we using this waiferx.com/Physics website and not myCuesta.edu?"

"Is there a lab book that goes along with this class?"

"Where did the nickname P-dog come from? There has to be a good story there."

"What's a song you always crank up when it comes on the radio?"

"What is your favorite type of music?"

20120821

Overheard: like really, first-day adds

Physics 205A, fall semester 2012
Cuesta College, San Luis Obispo, CA

(Overheard after the end of the first day of class, with several waitlisted students attempting to add into an impacted class.)

Student 1: "I would really like to add into this class."

Student 2: "There are a lot of us who would like to add into this class."

Instructor: "I can't add any of you into this class. I can't promise a space unless there are no-shows or drops."

Student 3: "Yeah, but we really like the way you taught this class today."

Student 4: "You're such a likable teacher, it's really hard not to want to add into this class."

20120809

Presentation: are we alone?

Adam Godley (Dr. Nogrady): "Today really marks the first stage of an unprecedented technological advancement. We have begun to identify a so-called 'Goldilocks planet.'"

Peter Berg (Director): "'Goldilocks planets' are planets that have a similar sun, a sun that burns about as bright as ours..."

Adam Godley (Dr. Nogrady): "...If a planet is too far away from its sun, it's too cold; if it's too close to its sun, it's too hot, but for an Earth-like planet, the distance is just right--potentially perfect--for sustaining life."

Hamish Linklater (Cal): "What we're doing is sending out radio signals into deep space..."

Peter Berg (Director): "...high-frequency signals, which are beacons saying, 'Hey, if you can hear this, we're out here, we're Earth, hello.'"

Adam Godley (Dr. Nogrady): "Ladies and Gentlemen, prepare to bear witness to the making of history."
(Video link: "Goldilocks Planet.")

Wait--isn't this from a movie or something?

Yeah, thought so.

This presentation will take a more serious look at the possibility of life elsewhere in the Milky Way, and discuss efforts in communicating with any advanced technological civilizations that may be out there.

First, estimating the number of advanced technological civilizations in the Milky Way.

This can be done using the Drake equation, which multiplies a number of factors that reflect more and more restrictive conditions for an advanced technological civilization to arise to calculate NC, the number of these civilizations just in our galaxy, the Milky Way. For the purposes of this discussion you do not have to memorize all of these different factors, but understand how they place constraints on the possibility of life, and the general trend from less to more restrictive conditions.

The first factor in the Drake equation is N*, the number of stars in the Milky Way. Recall that we can only see the stars in our immediate vicinity, but by estimating the overall size of the Milky Way, we can derive a relatively certain value for the number of Milky Way stars. This is the most certain of all the factors in the Drake equation, and we these values will progressively get less and less certain as we go through the rest of the equation.

The next factor fP is the fraction of stars in the Milky Way that have planets. More specifically, terrestrial planets, or rocky moons around gas giants, both of which must have formed after the Milky Way sufficiently increased in metallicity over time. This is actively being measured by NASA's Kepler Space Telescope, as well as other Earth-based telescopes.

And of the stars in the Milky Way that have terrestrial planets, the next factor nHZ is the number of planets that would be in their stars' habitable zone--making them "Goldilocks planets"--not too close and not too far from their stars, such that liquid water (or some other liquid that can readily dissolve and hold nutrients) can exist. Although not very water-bearing planets have been verifiably discovered, many candidates have been recently found.

The next factor fL is the fraction of these potentially habitable water-bearing planets that life actually arises from chemical evolution. There is currently no way to even estimate this factor other than giving pessimistic values (even with the right conditions it is not likely life will ever arise) to more optimistic values (with the right conditions, life is likely to eventually arise). At least some constraints can be placed on the stars that may potentially harbor life on water-bearing planets, taking into account that life on Earth took approximately a billion years to arise, which would eliminate short-lived massive stars. However it is possible to attempt to make some estimates of this value by investigating other places within our solar system where liquid water exists, or has existed in the past (which locations might these be?). If life or some remnants of life are found, then perhaps it is likely that life can arise with the right conditions, or if no sign of life in our solar system is every found, this may suggest a more pessimistic value for fL.

The remaining factors in the Drake equation begin to be classified as "SWAG" ("Scientific Wild-A__ Guesses"). Such as fI, which is the fraction of life, once it starts, that will eventually evolve and become intelligent enough to develop technology that we can communicate with. There is currently no way to scientifically determine this factor.

And the last factor in the Drake equation is even less answerable: FS, the fraction of a star's main-sequence lifetime that an advanced technological civilization will survive, whether a short time (due to destroying itself through nuclear war, biohazards, climate change, etc.), or being able to survive a long time by avoiding such calamities. Again, there is no way to even begin to scientifically determine this factor.

So the Drake equation starts out with well-established values, and multiplies progressively less reliable factors to estimate the number of advanced technological civilizations in the Milky Way. The last few factors can be filled in with pessimistic values--perhaps it is not likely that life will arise, even with the right conditions; life probably would have a tendency to remain boring; and an advanced technological civilization would probably extinguish itself in a short time anyway. With such pessimistic values, the Drake equation results in only one advanced technological civilization in the Milky Way, which has to be us, and we are alone.

But what if more optimistic values are placed into the last few factors in the Drake equation--perhaps life is very likely to arise given the right conditions; life has a tendency to evolve more intelligence; and an advanced technological civilization would probably work things out to ensure its survival in the long run. With such optimistic values, the Drake equation results in a large number--possibly 10 million--of advanced technological civilizations in the Milky Way, of which we are one, and we are not alone.

These two estimates wildly vary because the last few factors in the Drake equation are filled with "SWAG." There is no way to solve the Drake equation to determine whether the number of advanced technological civilizations in the Milky Way are one, or 10 million, or somewhere (anywhere?) in-between these values.

Second, instead of trying to solve the Milky Way, how about searching directly for other advanced technological civilizations in the Milky Way? SETI is the "Search for Extra-Terrestrial Intelligence," while BETI is "Broadcasts to Extra-Terrestrial Intelligence." (This is getting back to the clip from Battleship (Hasbro, 2012).)

The Arecibo Observatory is a large radio telescope in Puerto Rico that has been used to listen for signals from other advanced technological civilizations. This is still being done at other radio observatories as well.

But in 1974, Frank Drake (of the Drake equation) decided to use a broadcast test from the Arecibo Observatory to send a message, anticoded using pulses for pixels to build up a simple, but information-packed message to whatever advanced technological civilizations that are out there...

...and we actually received a reply to this message in 2001, at the Chilbolton Observatory in Hampshire, England. However, this "reply" was not sent to us as an anti-coded radio signal...

...but appeared as a crop circle in the field adjacent to the Chilbolton Observatory. With tongue planted firmly in cheek, let's consider the following: (a) this crop circle appeared overnight, next to a radio telescope manned by technicians working overnight; (b) unemployment is very high in this rural part of England; (c) many tourists come to rural England to look at the new season of crop circles; (d) many of these tourists eventually eat, drink, and board at the local pubs and inns. Draw your own conclusions.

In the subsequent in-class activity, you will decipher a simple anti-coded message, and try to decipher the purported Chilbolton "reply" by comparing it to the original Arecibo message.

20120806

Presentation: origin of life(?)

"Hello! I'm Julia Child. I'm in my own kitchen today and I'm boiling up some primordial soup. And there is a primordial soup machine. We're doing a recipe for the chemical building blocks of life, today, at the Smithsonian..."

"Now I'm going to turn the machine on, and you're going to see how it works. There we go! Now here, here is the vapor is being vaporized, up here, goes through this tube, and gets zapped by these electric sparks. And the atmosphere falls down, and is condensed, and falls down, and is recirculated again. Now I'm going to turn the machine off."

"Well, pretty soon, with this continual exchange from soupy sea, to gaseous atmosphere, and down to soupy sea again, always going through shocks of energy, we're going to be making almost all of the chemical components--the building blocks of life..."

"Of course, the next step is, how to put these chemical building blocks together. Can we make life? And is this the way life began on this Earth? Who knows? And is this same process taking place on other planets? We don't know yet! But according to the laws of probability, it certainly could be. So that's all on the chemical building blocks of life and primordial soup. This is Julia Child, bon appétit!"
Wait, was the the real Julia Child? Wait, wait--who is Julia Child? (Video link: "Primordial Soup, with Julia Child (1976).")

This presentation will address the origin of life on Earth.

First, coming up with a working definition of life.

Ever play this board game as a child? Just what was goal of this game? If any of you are parents, then the ultimate goal of this game is to keep children occupied for a good thirty minutes or so, no matter who wins, or what happens during the game itself. Let's start with a working definition of what something living does (as opposed to what a living thing is): it should manipulate its environment (eat, build, destroy, etc.) in order to grow and make a new generation of things that can manipulate its environment.

In order to do things that livings things do, and more importantly, to make sure that a future generation is able to continue doing these things requires a lot of instructions to be stored. On Earth this information is typically encoded in long, complex sequences of carbon molecules (although it is speculated that some other types of chemicals might instead encode this information).

One last thing to add to our working definition of life--in order to survive changes in the environment, a living thing should be able to adapt, either in its own lifetime, or through changes in successive generations. Because conditions on Earth change over time, then living things on Earth have also changed over time.

Second, a timeline for how life arose on Earth. There are two things to consider here: first is that initially these steps take a long time to happen, but each successive step takes a shorter and shorter time to occur, so the rate of change speeds up over time. Second thing to consider is that this sequence of events is a hypothesis, and we will present evidence for each step, whether through recreation of similar conditions, or fossilized remnants--but to be completely honest, there will be one step in particular that has yet to be recreated or remnants to be found for, and we will be sure to point this out.

Atoms have a tendency to hook up with other atoms to make simple and complicated molecules, as long as there is enough energy and enough time. It is not difficult to have "building blocks"--simple molecules--assemble naturally in a short amount of time. This isn't life yet, but it's a start, and can be readily demonstrated by recreating conditions expected of early Earth, as did Julia Child in the video clip at the start of the presentation.

Chemical evolution is not life yet, either, but is the process by which simple molecules will assemble to form more and more complicated molecules, given enough energy, the proper conditions, and enough time. Here is a simulation of atoms and simple molecules eventually building longer and longer molecule chains. This is observed to happen naturally as well, and is also what you do in laboratory if you ever need to take organic chemistry. (Video link: "Formation of fatty acids in a geyser.")

Eventually longer and longer molecular chains will build up, and at some point will begin to manipulate the environment and make new generations of itself. This is the step that there is no fossil remnants for, and has yet to be observed in nature or deliberately created in the laboratory. But this is actively being pursued, and as to whether this can at least happen in the laboratory or be observed in nature, as Julia Child points out, "who knows?"

The simplest life is basically long molecular chains that contain enough information to manipulate its environment and make new generations of itself by surrounding itself with a protective cell wall, and being able to grow large enough to divide itself into multiple copies. While a single cell does not leave much (if any) trace of itself when it dies, colonies of single-cell organisms will leave behind substantive evidence of their accumulated changes to their environment. Fossil remnants of these colonies are found today (some with current generations still alive), and can be dated to about 3.4 billion years ago. Compare this to the approximate age of Earth (about 4 billion years as a hospitable planet), we can infer that it took a long time (approximately a billion years) for the simplest form of life to arise from atoms and molecules. (Video link: "Chilodonella uncinata dance.")

Life gets more and more complex from here, as single cell organisms progress to larger organisms made of many, many cells working collectively underwater. Living things start looking less like stuff that will make you sick if you ingest it, to more tasty and nutritious forms about 0.6 billion years--relatively very recently. So if you ever build a time machine, and forget to pack a lunch, don't go much farther back in time than this, or you'll starve to death.

Now each consecutive step for life to become more and more complex will happen faster and faster. Not long after complex life started in Earth's oceans, complex life arose on land, as determined by fossilized remnants.

And then not much longer after that, life on land begins to become complex enough not only to become more populous, but to radically change its environment to do so.

So it took a while for simple life to arise from atoms and molecules, and then become more and more complex from the oceans, onto land, and so far, us.

And we humans in terms of at least being capable of technological civilizations are extremely recent newcomers, only 0.003 billion years ago. In the subsequent presentation where we consider the possibility of life elsewhere in our galaxy (and how we might communicate with them), keep this timetable in mind. While we cannot be sure that life elsewhere (if it exists) would arise in the same way as it did on Earth, it is plausible that it would take approximately the same amount of time for simple life to naturally arise, and the rate of change in the complexity of life forms would accelerate with each successive step.