You may begin your lesson with a presentation of a video or numerous pictures depicting different galaxies. Trigger a small conversation with your class by asking your students what they know about galaxies in general.
You may inform your students about what they will do during this exercise.
Ask your students to pick an image and comment on what they see Initiate a conversation by asking questions on the structure of the depicted galaxies. This will help you understand what they already know on the subject.
Ask your students whether they can imagine how such galaxies are formed. Discuss with them how could these shapes have been created and introduce the central idea of investigating the past of galaxies and the universe in general by creating respective simulations. Note down their answers.
Inform your students that you are going to start your investigation be making observations of galaxies, just like astronomers do.
After we retrieve our observation we will study the morphology of the galaxy and attempt to reproduce its shape using a ‘ Galaxy Crash ’ simulation.
Useful tips: It is thought that NGC 5195 has a mass of about 30-50% the mass of M51. In recent simulations of these two galaxies, astronomers - among other parameters - varied the angle of inclination (theta) for M51 between 10-30 degrees, and for NGC 5195, between 25-50 degrees. Astronomers believe NGC 4038 to be the result of a collision between two spiral galaxies of similar mass. In recent simulations of this galaxy interaction, astronomers incline both galaxies at 60 degrees to the orbital plane (i.e. theta = 60 degrees). Try not to change too many parameters at once in a run. See how each parameter individually affects the simulated galaxies first. Remember, we are only seeing the above observed interactions from one viewing angle, so click and drag the view of the simulation to see the interactions from different angles to see which best match our observations. The smaller the value for Peri, the stronger the tidal interaction between the two galaxies, but also, the faster the interaction, so long tidal tails may not form. The larger the value for Peri, the slower the interactions, but the weaker the tidal interaction between the galaxies, so again, long tidal tails may not form!
Compare the parameters each team used in order to produce the images of the galaxies. Check if all teams have used more or less the same parameters, if not discuss about the different scenarios regarding the formation of the galaxies under investigation. Students will refer to their initial predictions and compare them to the results of their research.
Crashing galaxies demo
CRASHING GALAXIES (INQUIRY BASED TEACHING)Tsourlidaki EleftheriaEllinogermaniki Agogi
GENERAL INFORMATION• Brief Description: The following exercise aims to introduce to students the concept of varying galactic morphologies. Students will try to investigate the origin of the shapes of the galaxies that stem from galaxy interactions.• Connection to the curriculum: Elementary education: Interdisciplinary courses, Astronomy: Galaxies Secondary education: Introduction to astronomy and space physics, Gravity• Age range: 9 – 11, 11 – 14, 14 – 16• Time required: 2 didactic hours• Technical Requirements: Computers with internet connection and flash Go-Lab platform• Keywords: galaxy, elliptical, spiral, irregulars, lenticular, Hubble
GENERAL INFORMATIONEducational Objectives:- Learn about the different shapes of galaxies.- Get acquainted with making and studying astronomicalobservations.- Learn about simulations and how they may be used in ascientific context.Cognitive domain (processes): to think critically and creativelyCognitive domain (knowledge): conceptual knowledge, procedural knowledgeAffective domain: to respond and participatePsychomotor domain: to adapt and perform creatively
QUESTIONS ELICITING ANSWERS :EXHIBIT CURIOSITY- What do these pictures depict?- How are galaxies created?- What would happen to our Galaxy if itcollided with another?
QUESTIONS ELICITING ANSWERS :EXHIBIT CURIOSITY During this exercise we will: - Collect images of galaxies using a robotictelescope- Investigate the origin of the shape of thegalaxy we’ll observe using simulations.
QUESTIONS ELICITING ANSWERS : DEFINE QUESTION FROM CURRENT KNOWLEDGE- How are galaxies formulated?- How many galaxies are there in the universe?- What is a galaxy composed of?-What is so special about the centre of galaxies?-Why are galactic centres so bright?
ACTIVE INVESTIGATION : PROPOSEPRELIMINARY EXPLANATION OR HYPOTHESIS - How can we learn how these shapes came to be? - How do you think these galaxies looked like before they started interacting? - What will happen to these galaxies in the future? - How long does it take for a galaxy to be formulated?
ACTIVE INVESTIGATION :PLAN & CONDUCT SIMPLE INVESTIGATIONChoose some of the galaxies indicated and makeobservations using the Faulkes telescopes.
ACTIVE INVESTIGATION : PLAN &CONDUCT SIMPLE INVESTIGATION NGC 4038 - The Antennae 12:01:52.68, -18:51:54.00 Coordinates: Filter: Color Exposure: 180 s M51 and its companion, NGC 5195 Coordinates: 13:29:53.16, 47:11:48.120 Filter: Color Exposure: 180 s
ACTIVE INVESTIGATION :PLAN & CONDUCT SIMPLE INVESTIGATION- We are now going to investigate the shapes of thegalaxies we observed. How was their shape created? How long did it take to be created? What will happen in the future? We are going to investigate the origin of these twogalaxies and answer the questions mentioned aboveusing a simulation. Just like astronomers do, we will try toreproduce the observed image using a simulation, in orderto understand the process behind the shape of theobserved image.•
ACTIVE INVESTIGATION :PLAN & CONDUCT SIMPLE INVESTIGATION- Go to the “Galaxy Crash” simulation- Look at the galaxy in the image you have obtained from thetelescope and try to recreate its shape by using the simulator. Inorder to do this, change the parameters in the panel and carryout numerous simulations until you achieve the desired result.- When the shape of the galaxy in the image resembles theshape in the simulation stop the simulation and make a print-screen. Insert your print screen in your notebook. If needed,prior to making your print-screen, rotate and enlarge the imagein the simulation in order to make a more accurate match tothe real image.
ACTIVE INVESTIGATION :PLAN & CONDUCT SIMPLE INVESTIGATION
DISCUSSION:EXPLANATION BASED ON EVIDENCE- Explain which parameters you used for your best model in thesimulations you have carried out. - How long did it take for this interaction to reach the observedstage? - Based on your simulation, describe how the current shape of thegalaxy has been formed. - Based on your simulation, what do you think will happen to thesegalaxies in the future? - What happens to the relative velocities of the galaxies as theyreach their point of closest approach (perigalacticon, or peri forshort)?
DISCUSSION:CONSIDER OTHER EXPLANATIONS- Do your team’s parameter match the parameterschosen by other teams?- Could there be any other different way to form thesame galaxy?- Do you conclusions much your initial predictions?
REFLECTION:COMMUNICATE EXPLANATION - What parameters are involved in the shaping of galaxies? - Why are spiral galaxies more active in terms of star formation? - How long does it take for a galaxy to form? What kind of galaxy is the Milky Way?