ast151 winter 2014 lecture 1

AST 251 | UofT | Dr. Rodriguez Hidalgo|

AST 251Life on Other Worlds

[email protected]

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mailto:[email protected]



Welcome!

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Is there life out there?

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Who is here to help you learn?

•Me = Dr. Paola Rodriguez Hidalgo

•+ Teaching Assistants

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Who are you?

•Who is from Toronto? Who is not from Canada? Who has more than 30‐min commute each way to come to class?

•Who is a first‐year student? Who has taken an Astronomy‐related course before? Who has seen the constellaPons in the Southern Hemisphere?

•Please, complete the Introductory Survey on Portal so we can learn more about you and your interests.

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Who are you?

•Who has a class right before this one?

‐‐> Change Pme of the beginning of the class: 4:15pm

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Who are you?

•Why did you choose this class?

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Basic Goals of this Course

Catalog Course DescripFon: Scholarly discussion of the probability that there are planets with life elsewhere in the universe, from the perspecPve of current ideas concerning the origin and evoluPon of the universe, the solar system and life. Search techniques and possibiliPes for interstellar travel and space colonies are discussed. Intended for life sciences students.*

* No pre‐requisites though.

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Basic Goals of this Course‐ Where are we in the Universe? How did the Earth form?

‐ What is Life? What are the condiFons for Life to survive?

‐ How are we searching for Life?

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Basic Goals of this CourseL1: Be able to describe, assess, and appreciate what our posiFon in the Universe is, what the Universe consists of, and the major Fmescales.

L2: Be able to idenPfy the key requirements for life on and beyond Earth, and assess the possibility of life beyond Earth and what it represents for humankind.

L3: Be able to describe and assess how we are carrying out the search for life beyond Earth in the Solar System and beyond.

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Basic Goals of this CourseL4: Be able to explain how we use the scienFfic method to develop new scienPfic knowledge, in parPcular applied to the new field of Astrobiology.

L5: Demonstrate criFcal thinking, reasoning in the developing of ideas, and criPcal reflecPon. Develop criFcal assessment of reference sources. Learn to criPcize construcPvely.

L6: Show clear and coherent communicaFon skills, both orally and in wriFng.

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Some of my Extra Teaching Goals

• SPmulate your curiosity.

• Transfer my passion for science to you.

• Help you become a more aware ciPzen of the world.

• Show you that you can enjoy learning about Astrobiology!

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How are we going to reach those Learning Goals?

•First half of each class: lectures, discussions, and quesPons/answers.

•Second half of each class: group discussions and acPve learning.

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Required Material

•TWO required textbooks:

1) Life in the Universe BenneV & ShostakAddison‐Wesley3rd ediFon (2010)

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Required Material

•TWO required textbooks:

1) Life in the Universe BenneV & ShostakAddison‐Wesley3rd ediFon (2010)

2) Life in the Universe ‐ AcFviFes ManualPrather, Offerdahl, & SlaterAddison‐Wesley2nd ediFon (2006)

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Required Material

• iClicker : Bring it to every class

Why?

‐ It helps me to get a sense of what you understand

‐ It helps you to remain engage in the class, get a sense of what you understand, and retain the material for longer.

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Required Material

• iClicker : Bring it to every class

Score:

‐ Half just for trying

‐ Other half if you answer correctly

‐ We drop your worst 3 days (including zero) of the semester

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Required Material

• Register your iClicker:

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• Pen/pencil and paper

• Basic calculator

•Outside of Class:

‐ Daily access to Portal


Required Material

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• Pen/pencil and paper

• Basic calculator

•Outside of Class:

‐ Daily access to Portal:

Contact InformaFon, Lectures, Announcements, Register your iClicker, Discussion Board, Course Outline, Course Calendar, and other Handouts.


Required Material

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•Total of 100 points during the semester


Marking Scheme

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•This is not an “easy A” or “bird” course

•No extra points will be offered


Grades

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• WriFng Centres

• Academic Honesty ‐‐ Plagiarism

hVp://www.wriFng.utoronto.ca/advice/using‐sources/how‐not‐to‐plagiarize

• Students with DisabiliFes


Final Comments

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http://www.writing.utoronto.ca/advice/using-sources/how-not-to-plagiarize




We want you to LEARN!

•If at any point you are having difficulPes with the course, contact us: on Portal, Office Hours, talk to me aler class or to your TA, e‐mail us at

[email protected]


We are here to Help!

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• What Pme works best for you?


Office Hours

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BC D

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AST 251 | UofT | Dr. Rodriguez Hidalgo| 26


Star Trek

Alien(s)

Astrobiology: Science’s Answer

We are science

detectives


‐ Where are we? What is “out there”? What are the condiFons “out there”?




‐ What is Life? Under which condiFons does it survive?



We seem to recognize “life” when we see it. But do we know what we are looking for?

When do we think that something is living? It grows? So do crystalsIt moves? So do cloudsIt eats, spreads and replicates? So does fire

We have no good definiFon of life.

What is Life?


The situaFon in analogous to the definiFon of water a few hundred of years ago, before we knew its chemistry.

What is Water? At that Fme, it could not be defined but it could be described and recognized.

What is Life?


Answer: Lavoisier showed (in 1783) that water consists of hydrogen and oxygen in atomic proporFons 2:1. Now water is defined as the chemical compound H2O.

What is Water?


IS THERE LIFE OUT THERE?

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‐ How can we search for Life?


Philosophical or ScienFfic QuesFons?

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‐ How can we search for Life?


What is Science?(and what is not?)

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What is Science?

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Also difficult to define

Careful observaFons of phenomena

Can we study past events?


What is Science?

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Also difficult to define

Careful observaFons of phenomena

Can we study past events?

Careful study of evidence


The ScienFfic Method

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1. Look2. Come up with rules 3. Look more carefully/ differently/elsewhere to test rules 4. If rules work, repeat 3. If they fail, go back to 2

Key ingredients:ObservationsRules that make predictions (aka models/hypotheses)Tests (i.e. more observations)


What is Science?

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Hypothesis. Must be tested observaPonally or by experiments.

Model. A system of hypotheses or a good, working hypothesis. Makes specific, testable predicPons.

Theory. A system of models which are known to work.

Law. A Theory that explains many experiments. (Newton’s law of gravity).

(There are exceptions, Einstein’s “Theory of General Relativity” explains more observations than Newton’s “Law of Gravity”)


What is Science?

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Hypothesis. Must be tested observaPonally or by experiments.

Model. A system of hypotheses or a good, working hypothesis. Makes specific, testable predicPons.

Theory. A system of models which are known to work.

Law. A Theory that explains many experiments. (Newton’s law of gravity).

Can a scientific theory be proved true beyond all doubt?


What is Science?

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Occam’s Razor

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“The simpler of two models or hypothesis is the ‘beVer’ one”


Verifiable ObservaFons

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The observaFons need to be repeatable

Do personal tesFmonials count as scienFfic evidence? Why?But, are scienFsts eyewitnesses?

It can be verified by anyone (with previous knowledge).


The ScienFfic Method

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In groups: Come up with an observaPon and a scienPfic method process to study it(5 min)


The Universe is beauFful

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The Laws of Physics and Chemistry are Universal

What about the Laws of Biology? ‐‐> We don’t know

How did life form on Earth? Under which condiFons it emerges? Where should we search for Life then? ‐‐> We need to know the condiFons


Mars now


(Possibly) Mars long Fme ago‐> condiFons change


Finding NO life would be a significant result

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But we think life seems plausible!

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EvaluaFng ScienFfic Sources

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Page 4 AcFvity Manual: Claims that sound scienPfic come to us from a variety of media sources. Imagine you saw the following 2 stories:

News Item A

Headline: Cancer Risk ReducEons May Lie in Foods We Eat

PublicaPon: New England Journal of Medicine

Author(s): Susan Yi and D.L. Strendinsky, Davidson‐Smith Univ.

News Item B

Headline: Blazing Laser Gun Cures Cancer from 1 Mile Away

PublicaPon: Healthy Living Times

Author(s): J. Clarke, Center for Healing without NarcoEcs ‐‐ Division of Laser Sales and MarkeEng



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News Item A




News Item B




When evaluaFng the scienFfic credibility of a news item, the 1st step is to consider if the claim is plausible from a scienFfic perspecFve. Which claim do you think seems more plausible? Why?



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News Item A




News Item B




Which publicaFon do you think seems most scienFfically credible? Why?



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News Item A




News Item B




Which author do you think seems most scienFfically credible? Why?



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News Item A




News Item B




Which author do you think seems most scienFfically credible? Why?


Readings for next week will be in the Class Calendar on Portal

(but you can start by reading Chapter 3: 3.1, 3.2 & 3.3)

ast151 winter 2014 lecture 1

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