April 12:
- The study guide has not changed in any substantial way. But here is the final version of Hints for Exam #2 V2.0, posted 12:30 am on Thurs Apr 12.
- What is "Apophis"? It is a NEO that ``...in 2004, Apophis was briefly estimated to have a 2.7% chance of impacting the Earth in 2029...''
- From NASA's NEO Program website: Near-Earth Object Testimony before the U.S. House of Representatives Subcommittee on Space and Aeronautics. In particular, see the link to the Apophis' 2029 and 2036 threat.
- Reminder: I will not be here for class next Wed and Fri, and instead Earl Towson will present lectures on the lastest missions to Mars. Earl is a great speaker so I think you'll enjoy these lectures. Make sure you read the Chapter on Mars in the textbook and the two articles in the Course Reader on the meteorite from Mars ALH-84001.

April 10:
- Here are the answers for Written Homework #2, Multiple Choice Questions
Information for Exam #2
50 multiple choice questions; you need a ParSCORE Student Enrollment scantron form (the big pink one), #2 pencils, eraser. No iPads, cell phones, netbooks, etc., allowed. (Calculators and slide rules are allowed.) Be sure to fill out your ParSCORE form correctly! If you have mistakes, you will lose points on your exam (1 point per error). Common errors include:
. + putting an extra zero in front of your Red ID
. + putting a blank in front of your Red ID (leave the last column blank)
. + filling in wrong digits on your Red ID.
. + not filling in TEST FORM A
. + not filling in EXAM # 001
*** Please fill in your scantron information BEFORE the exam. ***
- If everyone fills in the scantron info correctly, I will award the class an extra credit point on the exam!
- Here are the instructions for the Exam: INSTRUCTIONS:
Completely fill out the ParSCORE Enrollment scantron form. Be sure to include your Red ID on the back as well as the front, and don't add a leading zero to your Red ID -- leave the 10th block blank. Leave the phone number and `code' part blank. Fill in `Test Form A' and Exam # 002. You will lose 1 point for each error on the form!
Use a #2 pencil only. Darken completely, and erase thoroughly if you change your answer. Be careful not to darken two answers.
There are 50 questions. Choose the best answer --- the questions are not designed to be tricky. You may leave anytime you are finished, but please be considerate and be quiet if you finish early. If you are confused by any question on the exam, please raise your hand to get help. It is too late to ask for clarification after you hand in your scantron. ** You may keep your exams to help you study for the final. **
But if you don't want your exam, drop it off and I will recycle it.
- Preview of Written Assignment #3: Part I. Multiple Choice: Ch 8 #35,37,40; Ch 9 #27,30,31,32; Ch 10 #29,30; Ch 11 #27,30,32,33,35; Ch 12 #25,26,32,33; Ch 13 #31,37. Part II. Find images related to astrobiology: An image related to Mars; Jovian planets (moons, rings, etc.); something biological/biochemical in nature; and something outside of the solar system. Explain the science content of the image.

April 5:
- Because I will be at SDSU's Mt. Laguna Observatory on Sun-Tue, I will not have office hours next Monday afternoon (Apr 9) or Tuesday (April 10).
- Reminder: Exam #2 on Friday April 13. The exam will consist of 50 multiple choice questions. Please use a clean, unfolded ParSCORE Enrollment scantron, and fill out the Red ID, etc. before the exam. You may lose 1 point for every error on your scantron form. Please fill out the information carefully. See the StudyGuide for details. Calculators are okay, but this is a closed-book exam: No PDAs, iPads, netbooks, iphones, cell phones, mp3, etc., allowed (slide rules are ok).
- Here is a rough-draft of preliminary hints for Exam #2. This is from a previous semester and will be updated next week.
- Lecture notes on: Chicxulub & the K-T extinction. Please review the notes on Jovian Planets, Meteors & Comets, since those go along with this topic.

Apr 3:
Welcome back! Hope you had a great spring break.
- Lecture notes on The Earth's atmosphere
- Lecture notes on: The Earth's interior.
- An "astrobiology A-Z" list: This list of ideas and topics in astrobiology can serve as a good review: by the time of the final exam, you should know the definitions and relevance of all the items on the list.

Mar 22:
Read the following about the possibility of life using arsenic instead of phosphorous: Life Built on Arsenic Discovery and Dispute.
Why Silicon Aliens Would Rather Eat Our Cities Than Us from Astrobiology Magazine.
- A historical perspective on the discovery of the Archaea: "30 Rings on the Tree of Life" from Astrobiology Magazine.


Mar 18:
- Lecture Notes: Comments on the Origin of Life on Earth
- Some helpful notes on Wien's Law (in .pdf format), kindly provided by former astrobio student E. Ross.
- Here is an important news story about the possibility of life using arsenic instead of phosphorous: Life Built on Arsenic Discovery and Dispute.
- If you participated in any of the SDSU Science & Engineering Sampler events on Saturday, congratulations, and I hope they were fun and useful activities. Please be sure to submit a short (typed) report of what you did so you can earn extra credit. The same applies if you participated (or will participate) in any of the many San Diego Science Festival events. The SDSU Science Sampler write-up is due on March 23, the San Diego Science Festival is due on April 2nd.

Mar 15:
-- Lecture Notes on: The Tree of Life
- How Life Shatters Chemistry's Mirror (Astrobiology Magazine), an article on the handedness of biomolecules. Besides being cutting-edge news, it contains good review material for this course.
-- Caution: The genetic code the table in the textbook on page 176 is non-standard(!): it lists the DNA codons, not the RNA codons. DO NOT use this table. Refer to the Course Reader for the standard RNA genetic code (or any intro biology textbook or even Wikipedia).
-- Q: The Solar System, and hence the Earth, is known to be about 4.54 billion years old. This is based on the age of meteorites and rocks from the Moon. But how do we know the age of these rocks? We use a technique called "radioactive dating". (No, this isn't about your ex-boy/girlfriend ...). The textbook discusses this on pages 108-112. Also, see the Teach Yourself #6 notes for more about radioactivity.
-- Reminder: If you find a mistake in the textbook, I will award you an extra credit point. Like most textbooks, their is misteaks. (sic)

Mar 11:
Jupiter and Venus are closest together on March 13, only 3 degrees apart. Notice how Jupiter moves past Venus and becomes closer to the horizon over the next 3 days.
- Here's that opening sequence from the film "Contact" based on the novel by Carl Sagan.
- Please do not fall to behind in the reading. We will cover the biochemistry and biology topics quickly. Please read the textbook and Class Reader material first, then ask questions in class when we cover those topics if anything is not perfectly clear.
- Although we won't cover this material in detail this semester, I strongly encourage you to read these notes, as it should help make some things clearer: Quick Intro to Chemistry

March 9:
Here is the homework question that isn't going to be collected or graded, but you really should know how to do this: + Part 3) Approximately at what wavelength (in nm) is the Sun's light at its maximum (peak) intensity? (Hint: you need to know the Sun's surface temperature accurately - look up a number accurate to 100 K and quote the source.) FULLY explain all steps: why are you doing what you are doing? Now comment on your answer: How does this wavelength relate to what we call the "visible light" portion of the electromagnetic spectrum?
+ Check out the Science & Engineering Sampler events on campus on Saturday March 17, in conjunction with SDSU Month and Explore SDSU.
++ Special Offer #9: Extra Credit: Participate in any of the San Diego Festival of Science & Engineering events, occurring Mar 17-24th. In particular, the SDSU Science Sampler on Saturday Mar 17 has many good activities. The amount of extra credit is based on how many activities you participate in: 1/2 point per activity (so do an even number!), up to 3 points for events at SDSU, and 3 more for other Science Festival events. Write up a half-page summary for each activity, stating what was done and what you learned. Like all assignments, this *must be typed*

March 8:
Another solar storm! From Fox 5 TV news on Thursday night: Earth Expected To Feel The Affects Of A Solar Storm (well, not much really...). Includes some footage shot at SDSU.
- Happy birthday to the Kepler Mission, launched 3 years ago!
- Lecture Notes on: Organic Molecules: The Molecules of Life
- We won't have time to go over the topic of basic chemistry this semester, and the course does not require that you know that material, but I recommend you read the notes as background information to get a richer and more full appreciation of the chemisty of life. They can be found on the "Teach Yourself" pages.
Special Offer #8: Extra Credit The CO₂ level in the atmosphere is currently about 390 ppm (parts per million), and we know that the level can go up and down due to natural causes (e.g. think of the ice ages). So what was the CO₂ level, not spanning a thousand years, but say, 100 million of years? For extra credit, investigate this topic and submit a short (1-page) write-up and include a graph of the level of CO₂ versus time. List the sources that you used. Note: You need to do more than just read Wikipedia! But you can use that as a good start. Due on April 2nd.

March 4
- Exam #1 Results: mean score = 38.7 / 50.0; median score was a very solid 41/50 (82%).
Approximate score-to-grade conversion (details given in class):
... A = 44-50
... B = 38-43
... C = 30-38
... D = 25-29. The grades are based on a curve, but the curve was very similar to curves from previous semesters.
- Unfortunately we did get the extra credit bonus for having properly filled out scantrons - but we came so close! Maybe next time we can get the extra credit.
- Lecture notes on: Venus
- Lecture notes on: Jovian Planets, Meteors & Comets
- Lecture Notes on: Organic Molecules: The Molecules of Life
-

Mar 1
- Final Version of Studyguide Hints for the first midterm.
- Here are the instructions for the Exam:
INSTRUCTIONS:
Completely fill out the ParSCORE Enrollment scantron form. Be sure to include your Red ID on the back as well as the front, and don't add a leading zero to your Red ID -- leave the 10th block blank. Leave the phone number and `code' part blank. On the back, fill in `Test Form A' and Exam # 001. You will lose 1 point for each error on the form!
Use a #2 pencil only. Darken completely, and erase thoroughly if you change your answer. Be careful not to darken two answers.
There are 50 questions. Choose the best answer --- the questions are not designed to be tricky. You may leave anytime you are finished, but please be considerate and be quiet if you finish early. If you are confused by any question on the exam, please raise your hand to get help. It is too late to ask for clarification after you hand in your scantron. ** You may keep your exams to help you study for the final. **
But if you don't want your exam, drop it off and I will recycle it.

Feb 28
- Lecture notes on: Venus
- REMINDER: Exam Information: 50 multiple choice questions; you need a ParSCORE Student Enrollment scantron form (the big pink one), #2 pencils, eraser. No iPods, iPads, PDAs, cell phones, netbooks, etc., allowed. (Slide rules are allowed.)
- Be sure to fill out your ParSCORE form correctly! If you have mistakes, you will lose points on your exam (1 point per error). Common errors include:
. + putting an extra zero in front of your Red ID
. + putting a blank in front of your Red ID (leave the last column blank)
. + filling in wrong digits on your Red ID.
. + not filling in TEST FORM A
. + not filling in EXAM # 001
*** Please fill in your scantron information BEFORE the exam. ***
- If everyone fills in the scantron info correctly, I will award the class an extra credit point on the exam!
- Calculators are allowed for the exam.
- Additional Teach Yourself material.

Feb 26
- Here are the solutions to the multiple choice questions in Written Homework #1.
- Exam Information: 50 multiple choice questions; you need a ParSCORE Student Enrollment scantron form (the big pink one), #2 pencils, eraser. No calculators, PDAs, cell phones, ipods, etc., allowed. (Slide rules are allowed.)
- Be sure to fill out your ParSCORE form correctly! If you have mistakes, you may lose points on your exam (1 point per error). Common errors include:
. + putting an extra zero in front of your Red ID
. + putting a blank in front of your Red ID (leave the last column blank)
. + filling in wrong digits on your Red ID.
. + filling in two answers bubbles because of sloppiness
. + not erasing an answer fully
Fill out your scantron form BEFORE the exam.

Feb 23
- Lecture notes on: Star & Planet Formation; The Solar System
- A bare helium nucleus moving at high speed is often called an "alpha particle", and it is a dangerous form of particle radiation that arises from radioactivity. Radioactivity come from nuclear fission which is the breaking apart of a nucleus - it is the opposite of fusion. Now that you know what an "alpha particle" is, why is the creation of carbon called the "triple-alpha process"? (teach yourself hints)
- The current homework assignment is to "Examine the NASA/JPL PlanetQuest website". This means fully explore the site, check out the links, and read many of the pages. Ask questions if there is anything that you don't understand. You should definitely expect exam questions to come from any website that is assigned for homework. Make sure you look at the "Planet Makeover" and "Alien Safari" sections.


Feb 21
- Reminder: Our first exam is next Friday.
- If you are presenting research at the SDSU Student Research Symposium and it conflicts with our class, please let me know.
- *DRAFT* Beta Version 0.1 Studyguide Hints for the first midterm exam. This is NOT the final version, but just a guide to get you started. The information in here is from last year, and it needs to be updated. The updated version will be posted later, and the final version next week on Tuesday or Wednesday night.
- Use the Teach Yourself web pages to help you learn the material.

Feb 20
Special Offer #7: Extra Credit If you read the article in the Skeptical Inquirer about Jane Doe by Loftus, turn in a brief summary of the article and your thoughts on what you read. The whole thing should be no more than 1 side of a page - keep it short and to the point. (Suggestion: Write 3 paragraphs total, 2 on the article and 1 on your opinion.) Since this is supposed to be a quick and easy extra credit, the offer expires on Wed Feb 22.

Feb 19
- Who was this guy Bruno that's quoted on the class web page? Read the Giordano Bruno biography from the Galileo Project.
- Reminder: Exam #1 Friday, March 2nd. It will consist of 50 multiple choice questions.
- Have you noticed Venus in the sky, over in the west just after sunset? And Jupiter somewhat overhead? On Feb 25 the crescent Moon will be close to Venus, and on the next night the Moon will be close to Jupiter.

Feb 16:
- Lecture Notes on Stellar Evolution
- Special Offer #6 - Extra Credit: I will award extra credit to students who come up with a good "favicon" for the class website. If we have enough entries, we can make a contest and let the class choose the best favicon. The winner then gets two doses of extra credit. No limit to the number of entries, but only one point of extra credit.This has to be an original favicon, and the name cannot be "favicon.ico" - the rohan server rejects them because there is a malware/virus called "favicon.ico". Special Offer #6 will end on March 1. E-mail me your files in gif, jpg, or png format for extra credit. Ideally the favicon will be easy to identify (even though only 16x16 pixels) as something unique to our astrobio class.

Feb 14
- Special Offer #1,2,3, and 4 are now closed.
- "More than ever, we'll need to constantly keep in mind that memory, like liberty, is a fragile thing." - Dr. Elizabeth Loftus, as quoted in New Scientist Magazine's story "Elizabeth Loftus forecasts the future" (18 November 2006). For more on the profound work of Dr. Loftus see the ``Critical Thinking, etc.'' section of our class web pages for links to (i) the Scientific American article (that unfortunately was poorly reproduced in the Class Reader); and (ii) a really fascinating, and even anger-generating article titled, "Who Abused Jane Doe? The Hazards of the Single Case History" printed in the Skeptical Inquirer. You can also visit Dr. Loftus' wwwebsite at: http://www.seweb.uci.edu/faculty/loftus/
- Lecture notes on: AGN

Feb 13:
- Teach Yourself (#3): This problem will help you understand the relation between Hubble's law and the age of the Universe:
Suppose the Hubble constant H₀ = 750 km/s per Mpc. How old would the Universe be? Do you think this is ok? (Here are hints for the problem.)

Feb 12/13:
- Happy Valentines Day from Mars! Click on the image to get the Mars Global Surveyor website.
- Lecture Notes on The Scientific Method and Critical Thinking
- Here's my cosmological thought of the day:
"Don't think of empty space as nothing;
Think of it as something with nothing in it."
For example, consider time. You can certainly measure it. And you have an intuition of what it is. But try to define it. One thing is for sure: it is something; it is not nothing. Well, that's about as good an explanation that I can offer. The notion of space stretching is not a trivial concept, so don't fret if it doesn't make sense immediately. For some, it will never make sense, and for those people I offer the following thought. Here is a very rough adaptation of a relevant section from Lao Tsu's Tao Te Ching, Book 11 (this not at all an exact translation, but I think it gets the point across):
"Consider the teacup:
It is not the sides of the cup that give its usefulness,
But rather the empty space they create."
- Special Offer #4 ("actors needed for extra credit") is closed.
- Special Offer #5: Here is a opportunity for a student with sufficient time to devote to this project to earn a significant amount of extra credit. Partial credit can be earned for effort. "Successful" means your proposal is accepted by NASA/JPL and you share the motivation and results in class. See the article called Pick a Pixel on Mars (2010 Jan 29) in Astrobiology Magzine. The idea is for you to actually determine what part of Mars will be photographed and examined next with the high-resolution imaging camera called "HiRISE". HiRISE is part of the MRO mission, a NASA satellite currently in orbit around Mars. See me for more details once you get started on this.

Feb 8:
- To prepare for the exams, try to answer all the multiple choice questions at the end of the chapters. If you have any doubts about what the correct answer is, please do ask. Also, at least read all the other questions and see if you can answer them. If you are confused or lost, please just ask for assistance - that's why I'm here. Finally, keep in mind that about 20% of the questions on the exam will be based on the Course Reader material - read each article carefully and ask questions if you are unsure about anything.
- Special Offer #4 - Extra Credit: For those of you who are theater majors, or actors, or wannabe actors, or who just like like to talk, I have a job for you. I need two students to act out a very short dialog between two friends. This 1-2 minute dialog will be in presented in class. I will provide the "script" ahead of time and all you have to do is slowly read it. The first two students who respond to this Special Offer will be asked to perform the dialog and will earn extra credit worth 1 exam point. No acting skill is necessary. (I used to have TA's help me with this, and boy, they definitely could NOT act!) Send email to the class email account if you are interested and I will send you the dialog.

Feb 6:
- Teach Yourself (#2): Try working out this problem - it will help you understand the Doppler effect:
The observed wavelength of the H-alpha line in a star is 653.450 nm. The true wavelength of the H-alpha line (measured at rest in the lab) is 656.255 nm. What is the radial velocity of the star? (Here are hints on how to do the Teach Yourself problems.)
- Lecture notes on: Cosmology & the big bang.
Special Offer #3: For extra credit on the homework, go to NASA's Astrobiology Portal and find the site about astrobiology in space exploration missions. Then (1) Simply list names of the current and past missions that have an astrobiology component. (There are 15 in total, one of which was the Apollo moon landings); and (2) Follow various links to find when and where the Mars Science Laboratory will land on Mars. Attach these a separate page to your Homework #1.
- Later this week, researchers may actually probe in the Lake Vostok, the 4th largest lake on Earth, but the most hidden - its undernear over 2 miles of ice! Located in Antarctica (where else?), it was discovered in 1996, and it is an extremely fascinating find for astrobiology. For almost a decade, astrobiologists have been working to get into the water without contaminating it will lubrication, antifreeze, etc. from the drill. They may succeed this week. If they do, we'll hear about it on astrobiology news.

Feb 3:
- Notice the planet Venus, visible in the southwest just after sunset. Venus is the third brightest celestial object (after the Sun and Moon), and sometimes is mistaken for a UFO by folks who don't pay attention to what's visible in the sky.
- To help clarify the written homework:
(i) You must answer all questions. The length of the homework should be about 3 pages total. It takes some time to write concisely, so don't rush (or leave this to the last minute). Hint: write your answers in full, then go back and edit your answers to shorten them and make sure they fit in 3 pages.
(ii) There are two articles in the Reader written by Carl Sagan. For the homework, the chapter called "Hallucinations" is the correct one. What are the main points the author is trying to make? What evidence or ideas does the author offer to support his/her point? Be sure to use proper college-level English. Use a spelling checker.
(iii) For the Astrobiology Magazine questions, make sure you give the title and date of the article.

Jan 30:
- Head start: Read news stories from "Astrobiology Magazine" for the next homework.
- Notes on atomic structure & spectroscopy. Remember, all class notes are copyrighted.

- Special Offer #2: Need help with some astronomy concepts? Confused by solar system vs. galaxy? Is a light year a distance or a time? "Parallax" vs. "parsec"? Hubble trouble? The first two replies to this "special offer" will be loaned an introductory astronomy textbook for the semester. (This is *not* the astrobio course textbook!) Send e-mail with your name and the words "Textbook" to the class e-mail account: astr310@rohan.sdsu.edu I only have two spare textbooks - sorry I can't loan out more.

Jan 26:
- Lecture notes on: Electromagnetic Radiation.
- If you find an error in the textbook, reader, notes, lectures, or web pages, please notify me and you may earn extra credit. The more important/significant the error, the more likely you are to earn extra credit. Please review the extra credit policy on our class Information and Policy webpage (and repeated below). In general, I don't award extra credit for spelling errors or typos and definitely not for updates/revisions to the Lecture Notes. But any major errors, like an incorrect date for an exam on the syllabus, would certainly earn you extra credit. Also, excellent questions (especially ones that help other students and show that you are really thinking) may earn extra credit.
- Please review the Safety Policies for this Class, and the SDSU Emergency Preparedness website: SDSU Emergency Preparedness.

Jan 24:
The solar storm activity continues - largest since 2003. Solar flares and coronal mass ejections are creating spectacular aurora. (And some other strange events, like a funny-looking SDSU astronomer talking about solar storms on Fox 5 TV News (www.fox5sandiego.com at 10 pm tonight...)

Jan 23:
There was a very recent "storm" on the Sun that ejected a lot of plasma (hot, ionized gas), and this material whizzed past the Earth over the weekend. The near-miss was generally harmless, and it did create some gorgeous aurora. The Sun continues to be active with large "solar flares" occuring, but again, with no danger, aside from some very high altitude satellites. For the latest, see spaceweather.com.

Jan 21:
- For those who may need help or a review of some mathematics, please read Appendix C of the textbook.
- Lecture notes: Parallax, Galaxies, & Large Scale Structure of the Universe.
- Teach Yourself (#1): Try working out this problem - it will help you understand the size and scale of the solar system: What is the minimum amount of time it would take to send a command to a robotic spacecraft on the surface of Europa? (Here are hints and more "Teach Yourself" problems.)

Jan 18:
- Lecture notes: You should be able to read the PDF files with almost any OS platform (linux/unix, Microsoft Windows,Apple/Mac, etc.). Here are the notes on the metric SI system and reference temperatures, lengths, and velocities.
- Lecture notes: What is astrobiology?
- Lecture notes: Stars, Vastness of Space, Clusters and Nebulae
- Special Offer #1: I have a few spare Course Readers that I can loan out for the semester. These were donated by good-citizen previous Astr 310 students. The first few students to send e-mail to our class e-mail account can borrow a Reader. Please put the words "Astrobio Reader" in the subject line of your message.

** All class notes are copyrighted. **


On-line Class Notes Policy:
The on-line class notes are available to augment classroom learning - their sole purpose is to prevent frantic writing of notes and allow students to spend time listening, thinking and comprehending the lecture. They are not intended to be, nor do they function as, a substitute for attending the lectures. For maximum value, you should: (i) read the homework assignments first (especially the textbook & web page reading assignments which cover material well before we discuss the topic in class); and (ii) bring the notes to the lecture so you can add comments, sketches of figures, and material not in the notes.
Treating the on-line notes as a substitute for attending class is inappropriate at best and detrimental at worst.
The on-line notes will NOT be available all semester - they are posted several days before the lecture, then removed a few days after the lecture - no exceptions. This is for the students' benefit. So please keep up with the class.

Reminder: The lecture notes, along with all other class material, are copyrighted.

Please don't confuse the terms "hypothesis" and "theory". As used in science, a theory is a very strong term and only a handful of ideas in all of science qualify as a theory. A hypothesis is an educated guess or explanation, and implies insufficient evidence or comprehension for a more concrete understanding. A theory is a well-tested, well-established hypothesis, able to make far-ranging predictions and connections with other theories, and usually with an elegant mathematical or physical mechanism for its operation. A theory is much stronger than a hypothesis. It has been rigorously tested by many independent people. When speaking in technical terms, don't use the word "theory" when you simply mean speculation or conjecture or idea or educated guess (all of which are synonymous with hypothesis). In science-speak, we don't come up with theories, we come up with hypotheses. But that's not the way the word "theory" is used in common conversation. Keep this in mind so you don't get confused when you hear someone say, "It's only a theory." That theory may encompass the sum total of all of human experience and knowledge! A better way to think of the word theory is to equate it with the word "law". That is closer to the meaning that scientists intend when they call something a theory.

Last major update on 2012 Jan 16. Updates occur frequently. k