Cuesta College North County campus star party

081120-1060659
http://www.flickr.com/photos/waiferx/3059302272/
Originally uploaded by Waifer X

Cuesta College Astronomy 210L students and guests from both North County and San Luis Obispo campuses during a North County campus star party. The SLO campus students made the inevitable In-n-Out Burger stop on the way back down the Cuesta grade.

Sights seen:
M57 (Ring Nebula)
M31 (Andromeda Galaxy)
M45 (Pleiades)
Epsilon Lyrae (The "Double-Double")
Aldebaran
Vega

Astronomy clicker question: reionization

Astronomy 210, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

Students were asked the following clicker question (Classroom Performance System, einstruction.com) at the end of their learning cycle:

__________ is/are evidence of reionization in the early universe.

(A) Galaxy redshifts are proportional to galaxy distances.
(B) The near zero curvature of space-time.
(C) The amounts of helium and lithium in extremely old stars.
(D) Extremely distant galaxies surrounded by neutral hydrogen gas.
(E) The cosmic microwave background.
(F) (None of the above choices.)
(G) (I'm lost, and don't know how to answer this.)

Section 70160
(A) : 4 students
(B) : 1 student
(C) : 3 students
(D) : 10 students
(E) : 8 students
(F) : 0 students
(G) : 0 students

Correct = 38%

Correct answer: (D)

Reionization occurred when the first generation of stars formed the first galaxies, at the end of the dark ages. The light from these stars ionized hydrogen around them, creating emission nebulae.

Astronomy clicker question: main sequence to neutron star evolution

Astronomy 210, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

Students were asked the following clicker question (Classroom Performance System, einstruction.com) at the end of their learning cycle:

A __________ main sequence star will eventually become a neutron star.
(A) massive.
(B) medium-mass.
(C) low-mass.
(D) (More than one of the above choices.)
(E) (None of the above choices.)
(F) (I'm lost, and don't know how to answer this.)

Section 70158
(A) : 33 students
(B) : 9 students
(C) : 1 students
(D) : 0 students
(E) : 0 students

Correct = 74%

Correct answer: (A)

Massive stars main sequence stars will become supergiants, undergo type II supernovae explosions, and then can either become black holes or neutron stars, depending on the mass of the remaining core.

Section 70160
(A) : 22 students
(B) : 3 students
(C) : 1 student
(D) : 0 students
(E) : 0 students

Correct = 85%

Kepler's third law: Galilean satellites

081116-1060598-invert
http://www.flickr.com/photos/waiferx/3035594981/
Originally uploaded by Waifer X

Tracker chart for the Galilean satellites of Jupiter, adapted from the "Jupiter Moon Tracker Results" data from the NASA Planetary Rings Node website (http://pds-rings.seti.org/tools/tracker2_jup.html), used to determine the mass of Jupiter using Kepler's third law.

Folded mountain range analog

081115-1060592
http://www.flickr.com/photos/waiferx/3032576847/
Originally uploaded by Waifer X

Carpet wrinkles, simulating a folded mountain range due to motion caused by plate tectonics.

The "Cooper Cooler(TM) Effect"

081106-1060446
http://www.flickr.com/photos/waiferx/3018649612/
Originally uploaded by Waifer X

Cooper Cooler(TM) apparatus in action for testing the hypothesis that an off-center impact on Uranus, which may have tilted its axis, would have also cooled it adversely due to stirring its interior, compared to Neptune, which would have remained relatively static, and cooled off at a slower rate. Two bottles containing equal amounts of warm water at the same initial temperature are either put into a Cooler Cooler(TM) beverage chiller, and spun while deluged by a cascade of ice water, or placed in a static ice bath for an equal amount of time. Afterwards, the final temperatures of the two bottles are compared.

Carbonaceous chondrite meteorite analog

081109-1060476
http://www.flickr.com/photos/waiferx/3016613907/
Originally uploaded by Waifer X

Raw spinach leaves versus cooked spinach leaves, as an analogy for meteorites containing carbonaceous chondrites (volatile materials which would not survive extensive heating, and thus may represent a sampling of the early solar nebula), versus achondrite meteorites, which lack volatile materials (and thus experienced extensive heating in its past).

Found physics: "Turkey/Cornish Hen Effect"

081108-1060468
http://www.flickr.com/photos/waiferx/3016610525/
Originally uploaded by Waifer X

The "Turkey/Cornish Hen Effect," illustrating the effect of mass on thermal capacity. Low-mass objects cool off much quicker than massive objects, which cool off at a slower rate.

Cuesta College North County campus star party

081108-1060468
http://www.flickr.com/photos/waiferx/3021862660/
Originally uploaded by Waifer X

Cuesta College Astronomy 210L students Nadia and Mary use digital cameras to take pictures through the eyepiece of one of the North County campus 8" reflectors during a North County campus star party.


081108-1060460
http://www.flickr.com/photos/waiferx/3021031647/
Originally uploaded by Waifer X

First quarter Moon (inverted), November 6, 2008, photographed with a hand-held Panasonic Lumix LZ-8 through a Meade LX200 8" reflector at Cuesta College North County campus, Paso Robles, CA.


081108-1060461
http://www.flickr.com/photos/waiferx/3021032599/
Originally uploaded by Waifer X

Cuesta College Astronomy 210L students and guests (aka "Starry Night Gangstas") during a North County campus star party.

Sights seen:
M57 (Ring Nebula)
M31 (Andromeda Galaxy)
M45 (Pleiades)
Epsilon Lyrae (The "Double-Double")
Alberio (Beta Cygni)
Vega
First quarter Moon

Erasing slate: I love this!

"I love this!" by Anonymous
November 5, 2008
Cuesta College, San Luis Obispo, CA

Latest scribbling on the lift-and-erase slate in the hallway, outside the office door.

Open, flat, and closed universes

081104-1060413
http://www.flickr.com/photos/waiferx/3003896971/
Originally uploaded by Waifer X

Models representing a negative curvature "open" universe, a zero curvature "flat" universe, and a positive curvature "closed" universe. The closed universe is constructed by removing two triangles from a flat sheet, and taping the resulting cutout edges together. These triangles are then taped into slits cut into another flat sheet, producing the open universe. The black-and-white inverted version of the same photo is shown below.

081104-1060413-inverted
http://www.flickr.com/photos/waiferx/3004952710/
Originally uploaded by Waifer X

Astronomy clicker question: Milky Way mass

Astronomy 210, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

Students were asked the following clicker question (Classroom Performance System, einstruction.com) at the end of their learning cycle:

The total mass of the Milky Way can be estimated by:
(A) observing how quickly or slowly stars at different distances orbit its center.
(B) observing how quickly the supermassive black hole at its center is growing.
(C) carefully counting all the stars in the night sky.
(D) timing all of the Cepheid variable stars in the halo.
(E) (I'm lost, and don't know how to answer this.)

Section 70160
(A) : 14 students
(B) : 6 students
(C) : 0 students
(D) : 7 students
(E) : 0 students

Correct answer: (A)

Kepler's third law would be used to determine the total mass of the Milky Way. (This clicker question sets up the introduction of dark matter.) Response (D) would determine the luminosity of the Cepheid variable stars, from which the their distances could be found, resulting in the distance of the sun from the center of the Milky Way. Response (B) is a somewhat fanciful notion.

Astronomy quiz question: evolution to stellar remnants

Astronomy 210 Quiz 5, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

[Version 1]

[4.0 points.] Which type of main-sequence star will eventually become a neutron star?
(A) Massive.
(B) Medium-mass.
(C) Low-mass.
(D) (None of the above choices.)

Section 70158
(A) : 34 students
(B) : 16 students
(C) : 8 students
(D) : 8 students

Correct answer: (A)

"Mass is destiny." Massive stars will become either neutron stars, or black holes; medium-mass stars will become white dwarfs, while low-mass stars become (and remain) red dwarfs, at least for now, given the current age of the universe.

"Difficulty level": 54%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.95

[Version 2]

[4.0 points.] Which type of main-sequence star will eventually become a white dwarf?
(A) Massive.
(B) Medium-mass.
(C) Low-mass.
(D) (None of the above choices.)

Section 70160
(A) : 0 students
(B) : 20 students
(C) : 5 students
(D) : 5 students

Correct answer: (B)

"Difficulty level": 69%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.42

Astronomy quiz question: red dwarfs as giants?

Astronomy 210 Quiz 5, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

A red dwarf will never become a giant because:
(A) it is made of degenerate matter.
(B) its core will never get hot enough to fuse helium.
(C) it will never run out of hydrogen to fuse.
(D) not a single red dwarf has died of old age anywhere in the universe.

Correct answer: (B)

A red dwarf has a main sequence lifetime much longer than the age of the universe, so none have actually "died" yet. However, when all of the hydrogen in a red dwarf has been depleted, it will gravitationally contract, but not enough to increase the temperature for helium to fuse, so it will never restart fusion to become a giant, as a medium mass main sequence star would at the end of its hydrogen fusion lifetime.

Section 70158
(A) : 2 students
(B) : 51 students
(C) : 6 students
(D) : 7 students

"Success level": 80%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.22

Section 70160
(A) : 1 student
(B) : 16 students
(C) : 8 students
(D) : 5 students

"Success level": 58%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.31

Overheard: large-impact hypothesis

Astronomy 210L, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

(Overheard in lab during an analysis of Moon formation theories, namely the large-impact hypothesis, where the Moon formed from the crustal debris flung off of the Earth from a Mars-sized protoplanet impactor.)

Student 1: "Wait...does that mean that the Moon is the Earth?"

Student 2: "What? The Moon is the Earth?!?"

Esprit d'escalier:
Instructor: "Dude! The Moon is the Earth. Have another brownie."