Transcript GEARS Workshop Monday - Georgia Southern University

GEARS Workshop Thursday
2012
Warm Up
• Howdy!
• Please add some more thoughts to paper
evals
• Please complete your morning warmup
Parking lot
Transit of Venus
• http://transitofvenus.org/education/teacherresources
Microobservatory – has lots of
images of Transit of Venus – June
5, 2012
Software link on your flash drive
http://mowww.harvard.edu/jsp/servlet/MO
.ID.ImageDirectory
•
•
•
•
•
•
Switching GEARS from
Supernova and Fusion
Search for extra solar planets
This is looking for planets around other stars
Not looking for objects orbiting the Sun
There is an app for that
And the resource for all things planet searchy:
http://planetquest.jpl.nasa.gov/
Engage: Demonstration
• Take a look at ONE of these ways to represent
a star with a planet as seen from a distant
observer on Earth (hint for leaders – use a
light bulb…)
• Brainstorm ways to find planets based on this
information
Engage: Planet demos
• Brainstorm how you might detect planets.
http://www.youtube.com/watch?v=WApazS6-mu4
[email protected]
[email protected] after May 1
Kepler Mission
•
•
•
•
Staring at a part of the sky for 3.5 years
Watching the brightness of stars
Looks for dimming of light from star
Periodically!
Make some predictions
•
•
•
•
See the daily agenda – 9:35 am slot. (or next slide)
Think about why you are making your predictions
Spend less than 7 minutes on your predictions
Write down your predictions AND YOUR
REASONING!
Which type of system make it easier to find
planets using this technique. If it doesn't
matter, write EQUAL CHANCE
1. Less massive stars or more massive stars.
2. Planets with orbits that are closer to circular
or highly elliptical orbits.
3. Face-on orbits or edge-on orbits.
4. Small diameter planets or large diameter
planets.
5. Small mass planets or large mass planets.
6. Planets close to star or planets far from star.
Now test your predictions
Explore: Transit Simulator
• Semi-major axis – average distance from star – see
ellipse definition
• Eccentricity – ellipticity – or deviation from round –
see ellipse definition
• Inclination – how much plane of orbit tilts as seen
from Earth. Face-on = 0 degrees. Edge on = 90.
• Longitude – angle that plane of orbit seen by earth –
think 2-D ellipse that you aren’t looking at from short
or long axis – but at an angle
Discuss
• What definition did your group use for easier to find?
Easier to find
• % flux change – bigger easier to see
• Frequency of dip – must balance between the
orbital period (e.g. 100 years vs. 1 year) and
the fraction of the orbital period the star is
blocked.
• Need to discuss normalized flux – 100% of star
light seen vs 99%.
• Other simulator used 0.1 instead of .99 to
represent a 1% drop.
Thinking about teaching
• How can using a simulation help students
understand science?
After play with sim
• Create a hypothesis
• Write a hypothesis in the form of "If xxx massive
stars make it easier to find planets then I expect to
see ________." What is your independent variable?
What is your dependent variable? What are your
controlled variables?
• What have you used as a structure or model to help
build your hypothesis? (i.e. what reasons do you
have for believing your hypothesis?)
Compare hypothesis
• What types of questions might your students
come up with?
• Is this suitable for a science fair?
• What constitutes a testable hypothesis?
• Where does this activity this fall on the Rigor
& Relevance Framework?
Good vs. Testable Hypothesis
• Hypothesis: If it is easier to find massive
planets then I expect to see more massive
planets.
• Testable with simulator or no?
• Discuss Testable hypotheses vs. Good
questions to ask.
Elaborate: Kepler Flash
• Assign multiple people to examine same star
to be able to compare answers.
• Form to complete for answers.
• Compare your results to someone else’s with
same object
Evaluate: Graphing Kepler
Data in Excel
• Now it is time to use the real deal
Kepler - Period
• Multiple ways to decide the period.
• Group discussion about what those methods
are.
Kepler Peer Review
• Compare results with other participants who
had the same planet.
• Provide a formal review of their results on
your whiteboard.
Kepler Planet - answers
The Atlas
• http://exep.jpl.nasa.gov/atlas/atlas_index.cfm
• (from http://planetquest.jpl.nasa.gov)
% difference, % error
• Is it appropriate to calculate the percent
difference or % error of your results with the
astronomically published results in this case?
• Discuss in groups.
Citizen Science & Kepler data
• http://www.planethunters.org/
• Kepler data for your own investigations – published quarterly
• A list (in Excel format) of candidates is published (as of Apr
2011) in directory:
http://archdev.stsci.edu/pub/kepler/catalogs/
Kepler candidates
• Or from link on News page
http://archive.stsci.edu/kepler/
• If you visit the html version – you can click on the
candidate and plot the light curves from publicly
accessible data. (Only the EX – not the STKS)
Corrected, Uncorrected
Demonstration #2
• Brainstorm some ways to detect planets using
this demonstration as inspiration.
• Hand out set of demonstrations for each
person.
Radial velocity
• Vs. tangential
• Video – introduction
• http://planetquest1.jpl.nasa.gov/Planet_Finde
r/planetfinder.html
• And Radial velocity
• Requires sound
Doppler Shift
•
•
•
•
•
Introduction to Doppler shift of light
Redshift
Blueshift
From radial velocity link in Planet Quest video
Must use spectral lines – otherwise is just
continuous shift to continuous…
• http://hyperphysics.phyastr.gsu.edu/hbase/sound/dopp.html#c3
Doppler Shift Lecture Tutorial
• Complete this exercise in groups of 2 to 3.
• This is designed to be completed while you
are discussing with other people.
• This is not designed to be completed on your
own. (despite the fact we keep assigning them
as homework)
Doppler Shift Misconception
• Summarize – depending on where are
– ABC red, yellow, blue stars
– Or spacecraft/planets
Habitable Zone
• Define it based on your understanding from
the simulation
• Whiteboard and defend your definition
Scientific definitions
• Mutually agreed upon by many
Habitable zone
• Defined as location in a solar system in which
a planetary surface could support liquid water
• Does not include greenhouse effect heating
(like on Earth)
• Does not include tidal heating – such as on
Europa
Why liquid water?
• Ties to other disciplines – chemistry, biology
Other speculations
• What else might be required for life?
• Might we find life?
• How might we look?
Carbon based/Silicon based
• How can a discussion of habitable zone be
used in biology, chemistry, physics?
Habitable Zones
• Presentations.. Of various levels of difficulty
• http://lasp.colorado.edu/~espoclass/homework/.../Astr3300_
sept14_18.ppt
• www.mpia-hd.mpg.de/EXTRA2005/talks/Franck.ppt
• http://phobos.physics.uiowa.edu/~kaaret/sgu.../L07_extrasol
arplanets2.ppt
• SETI Institute Resources for Educators.
http://www.seti.org/seti-educators
•
(look what you could do next summer… http://www.seti.org/seti-educators/asset )
Making connections
• Does this content tie to anything you teach?
In 2020, a spacecraft lands on Europa and melts its way through the ice into the
Europan ocean. It finds numerous strange, living microbes, along with a few
larger organisms that feed on the microbes.
a.
b.
c.
d.
This is likely because biosignatures were already detected on Europa by the
Voyager 2 spacecraft.
This could happen because there is evidence for an ocean underneath the icy
surface of Europa and water is a good place to look for life.
This is fantasy because it would take more than 10 years for a spacecraft to reach
Jupiter using current rocket technology.
This is fantasy because the X-ray emission from Jupiter has effectively sterilized
all the moons around it.