Two Activities:1. A Paper Tape Scale “Solar System”

2. The Size and Age of the Universe from Supernovae

(both in early pilot)

Two Activities:1. A Paper Tape Scale “Solar System”

2. The Size and Age of the Universe from Supernovae

(both in early pilot)

Carl Pennypacker

HOU Conference, June , 2009

Carl Pennypacker

HOU Conference, June , 2009

Learning Goals:Learning Goals:Students learn:

• Real size and scale of solar system planets and distances

• Use of ratios in making scale models

• Distance = speed x time

• 1/R2 Law for brightness vs. Distance (Quick Cams!!)

• Expansion and Age of Universe

Students learn:

• Real size and scale of solar system planets and distances

• Use of ratios in making scale models

• Distance = speed x time

• 1/R2 Law for brightness vs. Distance (Quick Cams!!)

• Expansion and Age of Universe

Note on Pedagogy:Note on Pedagogy:

• Elicit Preconceptions

• Make a first attempt model

• Discuss the Why of their model in groups, class, etc.

• Measure/evidence

• Make a new model

• Elicit Preconceptions

• Make a first attempt model

• Discuss the Why of their model in groups, class, etc.

• Measure/evidence

• Make a new model

Make a Paper Tape “Solar System”!Rich Lohman has co-developed this unit

(Just Earth, Sun, and Jupiter)

Materials:

Make a Paper Tape “Solar System”!Rich Lohman has co-developed this unit

(Just Earth, Sun, and Jupiter)

Materials:

• 5 meter paper tape 1 AU = 1 meter

• Big sheet of paper for Sun, Earth, Jupiter

• Protractors (string) for making “Big” circles for scale sun- planets

• Scissors for cutting out planets

• Meter Stick

• Tape

• Work sheet (for refining estimates)

• 5 meter paper tape 1 AU = 1 meter

• Big sheet of paper for Sun, Earth, Jupiter

• Protractors (string) for making “Big” circles for scale sun- planets

• Scissors for cutting out planets

• Meter Stick

• Tape

• Work sheet (for refining estimates)

Make a Paper Tape Solar System(cont)!Make a Paper Tape Solar System(cont)!

• Assume 5 meters is distance from Jupiter to Sun (= 5 “AU’s”

Earth is at 1 AU -- the Sun is at one end, Jupiter at other.

1 AU = 1 meter is the distance from the sun to the earth.

• Without thinking, search your heart and emotions for the best size circle (draw and cut out) that matches the scale size of the Earth, the Sun, and Jupiter. Students usually make sun as big as paper. They seem to get ratios right, though.

“There Is no wrong answer!! Go for it!”

• Share your model with the class -- why do they choose these models. Let them luxuriate in these neurons and synapses of their great first models!

• Assume 5 meters is distance from Jupiter to Sun (= 5 “AU’s”

Earth is at 1 AU -- the Sun is at one end, Jupiter at other.

1 AU = 1 meter is the distance from the sun to the earth.

• Without thinking, search your heart and emotions for the best size circle (draw and cut out) that matches the scale size of the Earth, the Sun, and Jupiter. Students usually make sun as big as paper. They seem to get ratios right, though.

“There Is no wrong answer!! Go for it!”

• Share your model with the class -- why do they choose these models. Let them luxuriate in these neurons and synapses of their great first models!

Make a Paper Tape Solar System!Make a Paper Tape Solar System!

• Go to computers and open SalsaJ, and measure the

size of the Sun, Earth, and Jupiter. Desktop:

Fireball.fts = Jupiter 1 pixel = 340 km

Sun = Sun1 1 pixel = 4100 km

Earth_from_mars = Earth 1 pixel = 220 km

• Go to computers and open SalsaJ, and measure the

size of the Sun, Earth, and Jupiter. Desktop:

Fireball.fts = Jupiter 1 pixel = 340 km

Sun = Sun1 1 pixel = 4100 km

Earth_from_mars = Earth 1 pixel = 220 km

Make a Paper Tape Solar System!Make a Paper Tape Solar System!

• Go to computers and open SalsaJ, and measure the size of the Sun, Earth, and Jupiter. Desktop:

Fireball.fts = Jupiter

Sun1 = Sun 1 pixel

Earth_from_mars = Earth

• Go to computers and open SalsaJ, and measure the size of the Sun, Earth, and Jupiter. Desktop:

Fireball.fts = Jupiter

Sun1 = Sun 1 pixel

Earth_from_mars = Earth

Make a Paper Tape Solar System!Make a Paper Tape Solar System!

• Find the size in kilometers of the Sun, Jupiter, and the Earth.

• Convert kilometers into millimeters by dividing by 150,000. (cookbook for now -- need to drill down!)

• Remake your model.

• Class Discussion -- have to figure out how not to make teacher seem like too much a smarty pants and students too naïve.

• Find the size in kilometers of the Sun, Jupiter, and the Earth.

• Convert kilometers into millimeters by dividing by 150,000. (cookbook for now -- need to drill down!)

• Remake your model.

• Class Discussion -- have to figure out how not to make teacher seem like too much a smarty pants and students too naïve.

Now: Shift Gears to Hubble Activity:A word about the Expansion of the Universe With M&M Cookie:

Velocities are reasonably easy to measureWith Doppler shift in spectra:A Challenge: How to measure Distance!

Calibrated Standard CandlesUse a known light source, measure how

bright it is -- what variable is left?

Calibrated Standard CandlesUse a known light source, measure how

bright it is -- what variable is left?

Quick Cam Activity:Discover dependence of Brightness ondistance for a Standard Candle:

1) Students make a model first -- draw a graph of measured counts of standard candle versus distance -- discuss

2) Take a standard light source, standard exposure with quick cam (or use reference “star”)

3) Measure images with Salsa J

4) Make a graph

5) Make a new model/law

Quick Cam Activity:Discover dependence of Brightness ondistance for a Standard Candle:

1) Students make a model first -- draw a graph of measured counts of standard candle versus distance -- discuss

2) Take a standard light source, standard exposure with quick cam (or use reference “star”)

3) Measure images with Salsa J

4) Make a graph

5) Make a new model/law

Why are all the Type Ia SNe of nearly the same brightness?Why are all the Type Ia SNe of nearly the same brightness?

When a star of near Solar Mass uses up all of its Hydrogen and Helium it collapses to a White Dwarf. (W.D.)

If the White Dwarf has a companion star then, for the right conditions, Mass can be Transferred to the W.D.

Type Ia SNe are due to the explosion of a W.D. This occurs when it reaches a mass of 1.4 M0 (the Chandrasekhar limit) from Mass Transfer

When a star of near Solar Mass uses up all of its Hydrogen and Helium it collapses to a White Dwarf. (W.D.)

If the White Dwarf has a companion star then, for the right conditions, Mass can be Transferred to the W.D.

Type Ia SNe are due to the explosion of a W.D. This occurs when it reaches a mass of 1.4 M0 (the Chandrasekhar limit) from Mass Transfer

`̀

The star of about the size of the Sun becomes a White Dwarf about the size

of the Earth.

The WD consists of carbon and oxygen nuclei and a free electron gas. The Supernova explosion occurs when the gravitational pressure exceeds the electron gas pressure.

The star of about the size of the Sun becomes a White Dwarf about the size

of the Earth.

The WD consists of carbon and oxygen nuclei and a free electron gas. The Supernova explosion occurs when the gravitational pressure exceeds the electron gas pressure.

Supernova Discovery and Measurement Sequence.Supernova Discovery and Measurement Sequence.

The Sky in ChileThe Sky in Chile

QuickTime™ and aMotion JPEG A decompressor

are needed to see this picture.

By Chris Smith at Cerro Tololo

\\ The Hubble SpaceTelescope

Supernova Light Curve and SpectrumSupernova Light Curve and Spectrum

QuickTime™ and aYUV420 codec decompressor

are needed to see this picture.

SNe Light Curves from the HST and ImagesSNe Light Curves from the HST and Images

Hubble Curves

Concordance between SNe, CMB and ClustersConcordance between SNe, CMB and Clusters

M

DarkEnergy:~70% Dark

Matter:~25%

Punchline: Energy budget of Universe

~25%

~70%

Expansion Activity #1Expansion Activity #1

Materials: (demo)1) One sheet (black)“Grid” of Universe at T=1

2) Transparency of expanded Universe at T=2 (red)

3) Transparency marking pen

4) Paper for making a table

5) Graph paper

Materials: (demo)1) One sheet (black)“Grid” of Universe at T=1

2) Transparency of expanded Universe at T=2 (red)

3) Transparency marking pen

4) Paper for making a table

5) Graph paper

Expansion Activity #1 cont.)Expansion Activity #1 cont.)

1) Tape down T = 1 Universe (paper)

2) Tape down with T = 2 Universe (transparency)

3) Tape down blank transparency and carefully draw arrows from the same “galaxies” at T=1 connecting them to the same galaxy at T=2

1) Tape down T = 1 Universe (paper)

2) Tape down with T = 2 Universe (transparency)

3) Tape down blank transparency and carefully draw arrows from the same “galaxies” at T=1 connecting them to the same galaxy at T=2

Expansion Activity (cont)Expansion Activity (cont)

4) What do you notice?

5) Untape and re-center on some random galaxy

6) Put arrows on that galaxyMath note: Speed = Distance/time

7) Record the distance to the galaxy and also the speed, which is the length of the arrow (need to understand this)

4) What do you notice?

5) Untape and re-center on some random galaxy

6) Put arrows on that galaxyMath note: Speed = Distance/time

7) Record the distance to the galaxy and also the speed, which is the length of the arrow (need to understand this)

Expansion Activity (cont)Expansion Activity (cont)

8) Make a table of distance from the origin and the velocity of each galaxy

9) Make a graph

10) Figure out an age (Hubble constant-1) of the Universe, etc.

8) Make a table of distance from the origin and the velocity of each galaxy

9) Make a graph

10) Figure out an age (Hubble constant-1) of the Universe, etc.

Expansion Activity (cont)

Sloan Supernova Strip Data

Expansion Activity (cont)

Sloan Supernova Strip Data

The Sloan Digital Sky Survey telescope undertook a focused study of a strip of the sky and discovered over a hundred Type Ia supernovae.

We have five good ones from them to use.

The Sloan Digital Sky Survey telescope undertook a focused study of a strip of the sky and discovered over a hundred Type Ia supernovae.

We have five good ones from them to use.

`̀

The Supernovae!

Data from Josh Frieman of the SDSS, University of Chicago

Coordinates, redshifts ( z = v/c, where c = speed of light).

SNID Redshift AKA RA DEC

1241 0.087 2005ff 22:30:41.41 -0:46:35.7

2308 0.148 2005ey 2:17:5.49 +0:16:49.1

5550 0.156 2005hy 0:14:23.59 +0:19:59.0

2422 0.265 2005fi 0:7:58.69 +0:38:17.5

5391 0.301 2005hs 3:29:22.08 -1:5:40.9

5844 0.311 2005ic 21:51:8.69 -0:50:34.6

The Supernovae!

Data from Josh Frieman of the SDSS, University of Chicago

Coordinates, redshifts ( z = v/c, where c = speed of light).

SNID Redshift AKA RA DEC

1241 0.087 2005ff 22:30:41.41 -0:46:35.7

2308 0.148 2005ey 2:17:5.49 +0:16:49.1

5550 0.156 2005hy 0:14:23.59 +0:19:59.0

2422 0.265 2005fi 0:7:58.69 +0:38:17.5

5391 0.301 2005hs 3:29:22.08 -1:5:40.9

5844 0.311 2005ic 21:51:8.69 -0:50:34.6

Decoding the SDSS:(in this activity, the SDSS is used to find the supernovae)

Decoding the SDSS:(in this activity, the SDSS is used to find the supernovae)

Decoding the SDSS (continued)Decoding the SDSS (continued)

Decoding the SDSS (continued)Decoding the SDSS (continued)

New Feature:Photometry Tool!

New Feature:Photometry Tool!

Photometry Tool: Measure How Bright an Object is!! Photometry Tool: Measure How Bright an Object is!!

Photometry Tool: Measure How Bright an Object is!! (find Sne first) 1) Click on photometry tool

2) Click on star you want to read 3) Read off intensity (in counts) (photometry measures all of the counts within a circular ring, and subtracts off background)

Photometry Tool: Measure How Bright an Object is!! (find Sne first) 1) Click on photometry tool

2) Click on star you want to read 3) Read off intensity (in counts) (photometry measures all of the counts within a circular ring, and subtracts off background)

Expansion Activity #2Expansion Activity #2

1) Measure Sne

2) Fill in the table

3) Calculate Distance (jiffy formula to convert counts to million light years)

4) Make a Hubble Diagram

5) Get age of Universe

1) Measure Sne

2) Fill in the table

3) Calculate Distance (jiffy formula to convert counts to million light years)

4) Make a Hubble Diagram

5) Get age of Universe

Future of this Unit:Future of this Unit:

1) “HPL-ize” these activities

2) More pilots (with you all??)

3) Put on web, etc.

1) “HPL-ize” these activities

2) More pilots (with you all??)

3) Put on web, etc.