Announcements Archive



Course grades have been submitted.

Have a nice Winter Break!



Our last class meeting will be devoted to Exam 3. A Study Guide has been posted since last Friday, and we are having a Help Session Wed. afternoon. The usual procedures apply: bring your UT Photo ID and arrive before 9:45 AM. This exam focuses on interacting binary systems, black holes, and GRBs (gamma-ray bursts); it is not a comprehensive exam. It is also the last exam of the semester: there is no final during Finals Week. Course grades will be posted on or before Fri., Dec. 14.

Have a nice Winter Break!



Quiz 8 was given Thurs., Nov. 29. It will be graded and returned in class on Tues., Dec. 4. We will re-take the first-day Background Survey that day, providing another participation credit point for those who need it.

Topics to be covered in Tuesday's class include GRBs (gamma-ray bursts), more about black holes, and answers to selected questions from the index cards on Nov. 29.

All students are expected to take Exam 3 on Thurs., Dec. 6. It will not be cumulative, but will focus on the last few weeks of material. A Study Guide will be posted, and office hours and help sessions will take place on Tuesday and Wednesday.



Scores and a feedback file for Exam 2.5 are now posted. We are just beginning to talk about black holes, and will continue after Thanksgiving. You should read ch. 9, 10, & 11 in Wheeler's book during the break. We have now had more than 20 points of participation credit through in-class activities. However, if you missed a couple of classes or cards, you can do Optional Homework 3, which is due at the start of class on Tues., Nov. 27. There will also be at least two more additional in-class activities, as well as Star Parties.

Quiz 8 on Thurs., Nov. 29 - not Nov. 27 as previously posted, will be an opportunity to improve your quiz total, and a good review for Exam 3 on the last class day, Dec. 6. All students are expected to take Exam 3, and there will be no make-up for it. However, it will not be a cumulative, all-semester exam, but instead will focus only on material covered since Exam 2.



Scores for Exam 2 are now posted on Blackboard. All students, whether or not they missed Exam 1 or 2, are welcome to take the make-up exam we're calling Exam 2.5, on Thurs., Nov. 15. This will cover the material from both of the earlier exams, and can replace an earlier missed or low-scoring exam. See the Study Guides for topics, resources, and review questions. There will also be a Help Session on Wed., Nov. 14, as usual.

We are now starting the last major unit of the semester: close binary star systems that tangle with each other in interesting ways, black holes, gamma-ray bursts, X-ray novae, and other exotic objects. The relevant reading is primarily chapters 9, 10, and 11 in Cosmic Catastrophes.

For those who are short on Participation Credits, you can continue to attend Star Parties for credit (up to 3 parties, 3 points), and you can also do Optional Homework 3, which is due Tues., Nov. 27 (see Homework page).



The Study Guide for Exam 2 is now posted (see Exams page). Relevant sections in the recommended books can be found on the Readings & Links page. The exam format will be similar to that of Exam 1, but on the material covered since Exam 1. Bring your UT photo ID to the exam; you will be asked to place it on the table in front of you during the exam. In order to receive credit for the exam, you must arrive no later than 9:45 AM, and no one will be allowed to leave until 9:50 AM at the earliest.

There will be a Help Session on Wed., Nov. 7 at the usual time and place. In addition, Prof. Dinerstein will address the most frequently asked questions from the index cards of last Thursday, partly in Tuesday's class, and partly in a posted feedback file. Exam 2 will be graded promptly, to give you information that may affect whether you decide to take Exam 2.5, the make-up exam, on Nov. 15. Taking Exam 2.5 cannot lower your grade; it will replace one of your earlier scores (on Exam 1 or 2), but only if this improves your overall course grade.



On Thursday, Oct. 30, we began talking about neutron stars and pulsars. There will be a quiz on Thurs., Nov. 1 on the topic of the aging and death of high-mass stars, as covered in the last two class meetings. Then we will launch into the subject of stars in interacting binary systems. The readings are mostly in Wheeler's Cosmic Catastrophes book at this point.

Exam 2 is coming up on Thurs., Nov. 8, which is after the official Q-drop deadline of Nov. 2. If you plan to drop the class, you need to bring the form to class on Thurs., Nov. 1 for signature, as the professor may not be available on Friday.



We are now well into the topic of the aging and death of single stars. We've discussed the evolutionary path of lower mass stars (up to 8 solar masses), and will have a quiz on this on Thurs., Oct. 25. Then we move on to higher-mass stars that die in supernova explosions. The Readings & Links page is being updated, and includes many sections in the assigned textbooks as well as some outside links.

Despite earlier announcements, we will have a Quiz on Nov. 1 after all, but this will be an extra quiz, which can make up for an earlier missed quiz or low quiz score. Additionally, if you are currently low on participation credits, you may wish to do the optional Homework due Tues., Oct. 30, which can provide 1 or 2 participation points (see criteria on the assignment slides).

The deadline for academic Q-drops this semester is Nov. 2. You should be checking Blackboard to see how you are doing; the letter-grade categories are spelled out on a table on the Exams page. All students are welcome to take the Make-up Exam on Nov. 15, in addition to Exam 2 on Nov. 8. The score on the make-up exam will replace that on either Exam 1 or 2, but only if the score is higher (only if it helps your grade).



We will have a Quiz on exoplanets on Thurs., Oct. 18. Graded exams and old quizzes were returned in class on Tuesday. If you did not pick your papers, you may obtain them during office hours or at the Wed. help session. If you have questions about credit you lost on the exam, first consult the feedback file on the Exams page. If you don't find the answer there (or don't understand it), then it is time to consult one of the T.A.s or instructor, or ask at the help session.

We are now talking about the last stages of life for low-mass stars, when they become red giants and, eventually, white dwarfs. See ch. 3 & 4 in Kaler, and ch. 2.1 - 2.3 in Wheeler.



Exam 1 is being graded and will be reviewed on Thurs., Oct. 11. There will also be a quiz Thursday, on recent material.

In the meantime, we will be moving quickly through the topic of brown dwarfs, and onward to exoplanets! Although our main textbooks have little information on this rapidly developing topic, an outline and some useful links are posted on the Readings & Links page. We will also be watching videos and animations on exoplanets in class this week. By the middle of next week, we will move into the topic of the aging and deaths of stars and will be picking up more readings from our two reference books.

We have now had opportunities to earn as much as 10 points of participation credit in class. Although we anticipate that another 12 - 14 points will be available in class, if you are low on points you may wish to attend a Star Party; be sure to check the link for instructions on how to earn credit for this.



Our first hour exam will be Thurs., Oct. 4. It will cover through the topic of HR diagrams of star clusters (topic III B on the Readings page). A Help Session will be held Wed., Oct. 3 at the usual time and place. The Study Guide for the exam is posted at the Exams link on this menu. If you haven't picked up your all of your graded Quizzes, you can get them during (any of) our office hours, or at the Help Session.

You must bring your UT photo ID to the exam. Bring pencils for the multiple-choice portion, which will be answered on a scantron sheet. Short essays will be written on the exam booklet, so no blue books are needed. You must arrive before 9:45 AM to receive credit for the exam, and no one will be allowed to leave the room until 9:50 AM at the earliest.



Our first hour exam will be Thurs., Oct. 4. It will cover through the topic of determining ages of star clusters from their HR diagrams, discussed on Thurs., Sep. 27. A Help Session will be held Wed., Oct. 3 at the usual time and place. The Study Guide for the exam is posted at the Exams link on this menu.

We will briefly go over the answers and frequently missed issues on the last two card activities and Quiz 3 on Tues., Oct. 2, and graded quizzes will be returned at the end of class.

If you have not yet purchased your copy of Wheeler's Cosmic Catastrophes you should do so as soon as possible. It will soon become relevant to what we cover in class, and the UT Co-op has started returning unsold textbooks to the publishers.



Quiz 3 on Thurs., Sep. 27, will be partly on spectra and partly on stellar properties. Some students are still confused about light and spectra, and it is important to understand this material in order to apply it to observing starlight. See the feedback files on the quizzes and cards, or go to a help session, for review. Also coming up is the first in-class Exam, on Thurs., Oct. 4. A Study Guide will be posted by Fri., Sep. 28.

The Card Activity for Sep. 25 is being handled as Homework. You may discuss it with other students, but should compose your own answer (not copied). Please turn in the card at the start of class on Sep. 27. You can find the question at the end of the class slides for that date, or on the new Homework link.

If you have not yet purchased your copy of Wheeler's Cosmic Catastrophes you should do so as soon as possible. It will soon become relevant to what we cover in class, and the UT Co-op has started returning unsold textbooks to the publishers.



We have now moved on to the topic of properties of stars in general, and how we are able to measure them. This will lead us into discussions of Main Sequence stars other than the Sun, the ranges of their possible properties, and objects too small to become real stars (which are called brown dwarfs). If you have Kaler's book, read through ch. 1 and most of ch. 2; otherwise, look for these topics in any introductory textbook. Some helpful links are, or will, posted on the Readings & Links page.

Our first major exam will be on Thurs., Oct. 4, with a help session the previous afternoon. A Study Guide will be available online no later than (and possibly earlier than) Fri., Sep. 28.



We will finish our review of the properties of light on Tues., Sep. 18, and there will be a Quiz on this topic on Thurs., Sep. 20. Then we will briefly review the forces and types of energy that play important roles in the lives of stars, before moving on to discussing stellar properties in general. See the Readings and Links page for suggested readings and some helpful websites on the topics we are discussing in class.

Help Sessions are now being held on Wed. afternoons, as well as weekly Office Hours as listed. If you have missed any in-class Activity Cards, you may want to attend a Star Party (see details at the link) to replace the participation credit.



On Thurs., Sep. 6, we discussed the topic of solar neutrinos. There are only a few pages on this subject in our assigned books, namely pages 21 - 26 in Wheeler. For an excellent, more detailed synopsis of the "solar neutrino problem" see "Solving the Mystery of the Missing Neutrinos," a column written by the late John Bahcall, one of the pioneers of this subject.

Next Tuesday we will finish talking about the Sun and begin a review of the properties of light and spectra. You may wish to reread this chapter in your introductory textbook. On Thursday, Sep. 13, we will have a short-essay quiz at the beginning of class, on what we have learned about the Sun. There will be a pre-quiz Help Session on Wed., Sep. 12, at the posted time and place.



We are continuing to talk about the Sun, now touching on its internal structure and how it produces energy. On Thursday we'll bring up the topic of solar neutrinos (see pages 21 - 26 in Wheeler). Class Slides and feedback on Thursday's Activity Card are posted on the corresponding pages (see menu).

Office hours and the weekly help session are available this week. Students who are feeling a little at sea, having forgotten much of their introductory astronomy course, may find it helpful to attend the help session. It will be held in Robert Lee Moore Hall, the tall building on the south-east corner of Speedway & Dean Keeton. Take the elevator to the 15th floor and bear to the left until you get to room 15.216B. The help session will be conducted in a small group discussion format; we will also answer specific questions that students may have.



At the first class meeting on Thurs., Aug. 30, students took a survey to assess their background knowledge in Astronomy, and were reminded that Ast 309N has a prerequisite of Ast 301 or the equivalent (a college-level, one-semester introductory astronomy course). We watched a video about solar storms and how they affect us on the Earth, serving as an introduction to discussing the properties of our Sun, the nearest star.

The complete syllabus is now posted, along with a few slides from the introductory class. Students may add this course up until Tues., Sep. 4, the end of the free add-drop period, but no later than that (exceptions are rare).