Announcements Archive



Course grades have been submitted.

Have a great summer!



This class will be complete after the class meeting of Thurs., May 3, when students may elect to take a Make-up Exam for any of the three previous hour exams. This can replace an earlier missed exam, or raise your exam score if you perform better on the make-up than the original exam. Study Guides are posted for all three hour exams (even though we did not originally have a study guide for Exam 1). As usual, you must arrive by 11:15 AM to take the exam; bring pencils and your UT picture ID. Any final Star Party slips should also be turned in at this time.



We are currently talking about black holes, in theory and in reality. There is relatively (ha!) little about this in Kaler, ch. 7, so it is especially important to attend class. There will be one last quiz on Thurs., Apr. 19, bringing the total number of quizzes to 7, so that the two lowest scores (or missed quizzes) can be dropped from the overall course grade.

A new column labeled PTOTAL has been posted on Blackboard. This is your total of Participation Points up to but not including the index card of April 12. The maximum number of points you may earn is 15. If you are low on points, you may wish to attend an upcoming Star Party (see Star Parties & Public Lectures page for details). Up to two Star Parties can count (1 point for each), but you must turn in a signed slip to receive credit. There will also be probably 3 additional opportunities to earn credit in class before the end of the semester.

Reminder: There is no final exam during exam week for this class. You may take a make-up exam for any one previous exam - whether missed, or a low score - on the universal make-up exam date of Thurs., May 3, but this is optional. If you do so, the higher of the two grades for that exam/unit will count.



We will have a quiz on Thurs., Apr. 5 based on what was covered in class on Tuesday, which can also be found in ch. 7 of Kaler. This was primarily on white dwarfs, with a brief introduction to pulsars through about 12 minutes of video.

Exam 2 is being graded; we anticipate that it will be completed by Thursday's class, enabling us to return the essay portions at the end of class.

One last reminder: there will be a Public Lecture that you can attend for credit on Wed., Apr. 4 at the time when we usually have a help session, but at a different location (see link for Public Talks). We have now had opportunities for 14 participation points through in-class activities. There will be several more such opportunities, as well as continuing Star Parties.



A Study Guide for Exam 2 has been distributed and is posted on this site; it includes lists of topics, readings in Kaler, key words, and 16 (!) review questions. For hints on how to use the Study Guide most effectively, see the last few slides for Mar. 22. The Exam will have the same format as Exam 1. You must arrive no later than 11:15 AM and cannot finish the exam before 11:20 AM; bring your UT photo ID and pencils! There will be a pre-exam Help Session on Wed., Mar. 28.

On Tues., Mar. 27 we will begin talking about the "aftermaths" of stellar deaths - the compact remnants left behind (white dwarfs, neutron stars). Some time will also be devoted to questions contributed by the class on the March 22 Card Activity. Additional questions can be sent by e-mail, although not every individual question will be answered in detail.

For students seeking to earn additional participation credits, there will be another Public Lecture you may attend for credit, on Wed., Apr. 4 (see Star Parties & Public Lectures page).



I hope everyone had a nice Spring Break!

When classes resume, we will continue our study of stellar life stories, now turning to the higher-mass stars that end their lives as supernovae. This is discussed in chs. 5 & 6 in Kaler.

Looking ahead, Exam 2 will be on Thurs., Mar. 29,, and will cover stellar aging in general. A Study Guide will be distributed on Thurs., Mar. 22. It will include a number of practice essay questions, and will thus substitute for an Optional Homework.



Exam 1 will take place on Thursday, Feb. 23. It will cover material discussed in class up to this point in the semester, much of which is also covered in Kaler, chapters 1 & 2. The exam will be partly multiple-choice questions (answered on scantron sheets) and partly short essays similar to those on the quizzes. Bring pencils and your U.T. photo ID. More details are given on slides 2 and 3 of the Feb. 21 slide set.

If you have remaining questions on the content of the Quizzes, Optional Assignment, or Participation Activities, feel free to come to our Office Hours or the Help Session on Wed., Feb. 22, or contact us by email.

Next week, after wrapping up a few details on exoplanets, we will begin the large topic of Stellar Aging, which means progressing through another type of "coolest stars" (red giants) in Kaler, ch. 3 to planetary nebulae containing "hottest stars," in ch. 4.



Quiz 1 was returned in class on Thursday. Many students did not do very well on this quiz. A detailed report and explanation of the correct answers is posted as a file on the Quizzes page. You will have an opportunity to (in principle) replace this quiz score on Thurs., Feb. 16, when we will have Quiz 2 at the beginning of class. In addition, we have posted a set of extra practice and review questions as an Optional Assignment. These will not be collected and graded, but can be the basis for questions and discussion at the Help Session on Wed., Feb. 15.

In terms of our schedule, we will be discussing brown dwarfs & extrasolar planets through Tues., Feb. 21. Since there are only a few paragraphs on these topics in ch. 2 of Kaler's book, so it is particularly important for you to learn this material by coming to class.

If you attended the Public Lecture on Saturday, your write-up must be turned in by Thurs., Feb. 16 in class.



Quiz 1 will occupy the first ten minutes or so of class on Thurs., Feb. 2. It will cover the material presented in class to date; also read ch. 1 of Kaler's book. The format is short answer essays: you choose two out of 3 questions, and write on the quiz papers.

We will finish our review of stellar properties by discussing the different lifetimes fof stars of different masses, and how to find the ages of star clusters (Kaler, pages 22 - 29). Next week, we will move on to objects off the bottom end of the Main Sequence: brown dwarfs & extrasolar planets.



On Tues., Jan. 24, we began a review of properties of light, discussed in a brief fashion on pages 3 - 8 of Kaler's book. We continue with a discussion of different kinds of spectra on Thursday, and will move on to a discussion of the observed properties of stars, including stellar spectral types (see Kaler, pages 17 - 19). Slides shown in class on Jan. 24 are posted; the slides relating to the "Solar Composition" question are in a separate file on the Participation Activities page.



In the first week of the semester we focused on both the surface and innards of our own star, the Sun. This material is only partially covered in the first half of ch. 1 of Kaler's book, so additional material was presented in class. (See Lecture Slides, from the menu at left.) Kaler addresses the behavior of light as electromagnetic radiation on pages 3 - 8, but we will discuss this topic in more detail in class on Tues., Jan. 24, and then move on to observed properties of stars (Kaler, pages 12 - 23). You may wish to review the relevant sections of your old astronomy textbook and/or notes, if you have these available.



Welcome to 309N! The course syllabus was distributed on Tues., Jan. 17, and is now posted (see link at left). Slides shown at our first class meeting are also posted; a large portion of the class period was devoted to a video on solar activity, "Secrets of the Sun." The current reading assignment is chapter 1 of the required book, "Extreme Stars" by James Kaler.

On Thurs., Jan. 19, we will discuss other aspects of our star including how it generates its energy, the saga of the "missing" solar neutrinos, and review how we read the messages of light. (The last topic should be familiar from your introductory astronomy course, although it's useful to refresh one's memory!)