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MESSAGE #219. Fri May 14 3:23:21 2010. TA: James Keane wrote:
Thomas - I can't help you with a review session, but as for apparent retrograde motion I recommend the following images. Geocentric Retrograde Motion Heliocentric Retrograde Motion Basically, we see that some planets in the night sky (Mars, Jupiter, Saturn, etc.) sometimes travel in backwards loops. Actual Image of Mars's Retrograde Motion Both the geocentric and heliocentric models needed to explain this. Geocentric model did so with epicycles. The heliocentric model naturally explained it as part of the circular orbits. The heliocentric model system turned out to be far simpler, and in the end - true.
As for stellar remnants, there is an ENTIRE chapter in the book solely on them (white dwarfs, neutron stars, black holes). I strongly suggest you read this chapter.
Leah - the review documents are located on the bottom of the "Assignments" page, which can be found on the ASTR100 homepage.
MESSAGE #218. Thu May 13 20:35:05 2010. Dummea Kumahle-Vincent wrote:
MESSAGE #217. Thu May 13 15:27:33 2010. Thomas Brooks wrote:
can anyone explain apparent retrograde motion? What are the contributions of the ancient greeks? can anyone explain the reasons why we get black holes and white dwarfs?
thanks
MESSAGE #216. Thu May 13 13:37:13 2010. Leah Loreman wrote:
MESSAGE #215. Wed May 12 6:08:34 2010. Prof. Doug Hamilton wrote:
Today is the last chance for CourseEvalUM - we are catching up to MWF ASTR100, but they still lead us in total response rate 63% to 58%! Take a break from studying and help us close the gap! :)
Don't forget tonight's review session and all of the ASTR100 office hours - you can see me or any of the TAs for extra ASTR100 help.
Kenny: Wednesday 2-6pm
Bryan: Wednesday 6-7pm
Review Session: Wednesday 7-9pm
Prof: Thursday 11am-2:30pm
Erin: Thursday 1:30-3:30pm
Good Luck with your studying!
DH
MESSAGE #214. Tue May 11 22:29:14 2010. Ricki Weinstein wrote:
MESSAGE #213. Mon May 10 9:32:55 2010. Emily Urciolo wrote:
I was just wondering if anyone wanted to have a review session in a smallish group this week?? let me know
emurciolo@gmail.com
Ps: I heard that Hubble 3d is supposed to be really cool!!! its an IMAX movie http://www.imax.com/hubble/
MESSAGE #212. Sun May 9 20:09:03 2010. TA: James Keane wrote:
More information on the benefit at Noodles can be found here: Noodles Benefit
More information on EFA can be found here: EFA
MESSAGE #211. Sat May 8 8:52:31 2010. Fana Mersha wrote:
http://www.universetoday.com/
MESSAGE #210. Sat May 8 8:46:09 2010. Fana Mersha wrote:
I was unable to attend the last class (may 6), so I was hoping to borrow someone's notes. We can coordinate when to meet via email. Or if you take notes on your laptop I would really appreciate it if you could email them to me! My email address is fana.mersha@gmail.com. Thank you!!
MESSAGE #209. Wed May 5 21:15:39 2010. Ivan Lochan wrote:
http://apod.nasa.gov/apod/
MESSAGE #208. Wed May 5 15:54:33 2010. Daniel Martinez wrote:
http://www.newscientist.com/article/dn8631-gravity-theory-dispenses-with-dark-matter.html
MESSAGE #207. Wed May 5 15:33:22 2010. Leah Loreman wrote:
MESSAGE #206. Tue May 4 16:04:41 2010. Barak Taragin wrote:
MESSAGE #205. Mon May 3 21:58:28 2010. Marci Goodman wrote:
MESSAGE #204. Mon May 3 16:05:44 2010. Leila Knoll wrote:
MESSAGE #203. Mon May 3 11:22:27 2010. Pratik Saripalli wrote:
MESSAGE #202. Sun May 2 8:52:13 2010. Prof. Doug Hamilton wrote:
I too am impressed with the lost Soviet reflector that they finally recovered on the Moon. It gives me hope that I may actually find my misplaced car keys ...
MESSAGE #201. Fri Apr 30 15:24:18 2010. Daniel Martinez wrote:
http://news.yahoo.com/s/space/20100430/sc_space/giantblizzardragingonsaturn
MESSAGE #200. Fri Apr 30 14:28:08 2010. Michael Kattouf wrote:
http://www.guardian.co.uk/science/2010/apr/30/stephen-hawking-right-aliens
MESSAGE #199. Fri Apr 30 12:25:01 2010. TA: Lauren Woolsey wrote:
I did a project on lasers and lunar reflectors for my physics of waves course (my goodness, that was already three semesters ago...). If anyone is interested in a little more information in a very simple powerpoint format, check out my old presentation, on slides 3-5. Enjoy!
MESSAGE #198. Thu Apr 29 9:42:20 2010. Earl Henthorn wrote:
MESSAGE #197. Thu Apr 29 8:50:40 2010. Ricki Weinstein wrote:
MESSAGE #196. Tue Apr 27 22:31:01 2010. Ricki Weinstein wrote:
MESSAGE #195. Mon Apr 26 23:48:04 2010. Nechama Yagod wrote:
MESSAGE #194. Mon Apr 26 23:15:13 2010. Prof. Doug Hamilton wrote:
As you've noticed, the pace of the class is picking up a bit - we are going to finish the book in just 5 more lectures! After getting this assignment in, get right on to the next chapter - HW#7 is due in 1.5 weeks and covers the last three chapters.
MESSAGE #193. Mon Apr 26 20:31:10 2010. Joseph Benik wrote:
MESSAGE #192. Mon Apr 26 20:17:04 2010. Daniel Martinez wrote:
And for number 18. The previous comment says we have all the tools to find D in order to find apparent brightness but I still don't know how to find D.
Thank you
MESSAGE #191. Mon Apr 26 19:17:29 2010. Nechama Yagod wrote:
MESSAGE #190. Mon Apr 26 19:15:13 2010. Joseph Benik wrote:
MESSAGE #189. Mon Apr 26 18:58:37 2010. Daniel Sullivan wrote:
MESSAGE #188. Mon Apr 26 18:53:33 2010. Joseph Benik wrote:
MESSAGE #187. Mon Apr 26 16:00:28 2010. Carol Downey wrote:
Plug the apparent brightness and the value you get for the luminosity into the distance equation to get the distance in meters.
For the second part, you are just comparing (your answer with the size of the universe) but you will have to do some converting. If I were you, I would convert your answer in meters to kilometers and then find out how big the universe is in kilometers. (1 light-year = 9.46 trillion kilometers and there are about 13.7 billion light-years from one end of the observable universe to the other). Good luck!
MESSAGE #186. Mon Apr 26 12:24:14 2010. Leah Loreman wrote:
MESSAGE #185. Mon Apr 26 8:55:50 2010. Carol Downey wrote:
MESSAGE #184. Sun Apr 25 21:51:10 2010. Ritchie Casimir wrote:
MESSAGE #183. Sun Apr 25 20:05:42 2010. Laura Miles wrote:
Check that link out! Its a really cool one, showing pretty amazing photos from the Hubble through the years!!
MESSAGE #182. Sun Apr 25 19:31:28 2010. Leila Knoll wrote:
Any ideas?
MESSAGE #181. Sun Apr 25 18:20:10 2010. TA: James Keane wrote:
Tonight's episodes are "Aliens" at 9pm, and "Time Travel" at 10pm.
http://dsc.discovery.com/tv/stephen-hawking/
~James Keane (0103 TA)
MESSAGE #180. Sat Apr 24 19:02:49 2010. Carol Downey wrote:
MESSAGE #179. Sat Apr 24 15:27:56 2010. Boban Dedovic wrote:
I am working on Question #21 on page 193 for the Chapter 11 questions.
11: Estimate how many galaxies are shown in the photo on page 1. Explain the method you used.
My logic would be to found out how many spiral/elliptical/irregular galaxies there are in general, and then find out how many stars each would contain.
However, I cannot find that information in the text!
Any insight?
Dr Hamilton, do you have any suggestions?
Sincerely,
Thanks,
Boban Dedovic, April 24, 2010, 3:27 PM.
MESSAGE #178. Sat Apr 24 12:39:25 2010. Pratik Saripalli wrote:
MESSAGE #177. Fri Apr 23 20:08:49 2010. Dummea Kumahle-Vincent wrote:
MESSAGE #176. Fri Apr 23 19:18:46 2010. Michael Sullivan wrote:
MESSAGE #175. Fri Apr 23 18:15:20 2010. Prof. Doug Hamilton wrote:
MESSAGE #174. Fri Apr 23 1:29:37 2010. Jordan Kamzan wrote:
http://www.stumbleupon.com/su/2cOmbt/news.ninemsn.com.au/glance/1043429/nasa-releases-stunning-sun-photos
MESSAGE #173. Fri Apr 23 1:16:06 2010. Eytan Hirsch wrote:
http://www.esa.int/esaSC/SEM0W1T1VED_index_0.html
MESSAGE #172. Thu Apr 22 1:29:47 2010. Daniel Sullivan wrote:
The extra credit is clicking one of the links under Stars & Stellar Movements
MESSAGE #171. Wed Apr 21 22:38:17 2010. Melinda Brennan wrote:
MESSAGE #170. Mon Apr 19 15:34:13 2010. TA: Lauren Woolsey wrote:
Don't forget that the exam review is this evening from 7pm to 9pm in your lecture hall (PHYS1412). Bring questions! Also, anyone and everyone is welcome to come by my office hours from 6pm to 7pm today to answer more individual questions or go over any problems you have.
Good luck! Lauren
MESSAGE #169. Sat Apr 17 18:11:13 2010. Joseph Benik wrote:
MESSAGE #168. Thu Apr 15 22:58:49 2010. Prof. Doug Hamilton wrote:
MESSAGE #167. Thu Apr 15 19:37:58 2010. Galina Bakaeva wrote:
MESSAGE #166. Thu Apr 15 16:40:22 2010. Daniel Sullivan wrote:
MESSAGE #165. Thu Apr 15 8:37:30 2010. Prof. Doug Hamilton wrote:
MESSAGE #164. Thu Apr 15 2:01:09 2010. Mario Pareja-Lecaros wrote:
MESSAGE #163. Thu Apr 15 1:59:58 2010. Mario Pareja-Lecaros wrote:
http://news.nationalgeographic.com/news/2010/04/100409-black-holes-alternate-universe-multiverse-einstein-wormholes/
MESSAGE #162. Wed Apr 14 22:40:07 2010. Prof. Doug Hamilton wrote:
It is a question of density - lots of mass smashed up into a teeny tiny volume and you got a black hole!
Still haven't posted the Eval. :( But I did get the HW solutions and review sheets up on the Assignments Page.
DH
MESSAGE #161. Wed Apr 14 18:33:37 2010. Sean Murphy wrote:
MESSAGE #160. Wed Apr 14 13:10:24 2010. Justin Chang wrote:
http://marctenbosch.com/miegakure/
MESSAGE #159. Wed Apr 14 12:18:38 2010. Ryan Carmody wrote:
http://www.pbs.org/wgbh/nova/pluto/mail-nf.html
MESSAGE #158. Wed Apr 14 11:25:43 2010. Karl Bohn wrote:
Theory of planetary formation now being disputed. Guess it's time for a new edition of our textbook.
MESSAGE #157. Tue Apr 13 21:00:24 2010. Prof. Doug Hamilton wrote:
The Evaluation Form is not posted yet - I got slammed with too many "Need this ASAP" assignments this afternoon. I'll work on it a bit later tonight and see if I can post it in the morning ...
MESSAGE #156. Tue Apr 13 16:31:22 2010. Kasandra Duckett wrote:
MESSAGE #155. Tue Apr 13 15:24:34 2010. Emma Witkowski wrote:
MESSAGE #154. Tue Apr 13 12:40:03 2010. Justin Chang wrote:
http://news.nationalgeographic.com/news/2010/04/100409-black-holes-alternate-universe-multiverse-einstein-wormholes/
MESSAGE #153. Tue Apr 13 10:58:57 2010. Justin Chang wrote:
MESSAGE #152. Mon Apr 12 23:57:12 2010. Yevgeny Deviatov wrote:
http://www.youtube.com/watch?v=oAVjF_7ensg
MESSAGE #151. Mon Apr 12 20:35:25 2010. Amy Young wrote:
MESSAGE #150. Mon Apr 12 16:29:03 2010. Carol Downey wrote:
So convert 1.5 solar masses to kilograms and solve for the volume of a sphere using the radius of the star in centimeters. You answer will come out in kg/cm^3.
MESSAGE #149. Sun Apr 11 23:07:32 2010. Leah Loreman wrote:
MESSAGE #148. Sun Apr 11 22:13:09 2010. Joseph Benik wrote:
MESSAGE #147. Sun Apr 11 21:29:16 2010. Ricki Weinstein wrote:
MESSAGE #146. Sun Apr 11 21:28:24 2010. Carol Downey wrote:
MESSAGE #145. Sun Apr 11 21:20:35 2010. Carol Downey wrote:
I could be completely wrong about this, so I would ask a TA or Prof. H. first.
MESSAGE #144. Sun Apr 11 20:58:23 2010. Ricki Weinstein wrote:
http://www.stsci.edu/jwst/science/drm/pdf/drm22.pdf
MESSAGE #143. Sun Apr 11 20:37:24 2010. Carol Downey wrote:
MESSAGE #142. Sun Apr 11 20:34:33 2010. Carol Downey wrote:
You have to use the equation M1+M2 = (4pi^2 x a^3)/(G x p^2) G = 6.67 x 10^(-11) and we already have a and p, so just plug it all in and you can get the sum of the masses. (I haven't checked my answer and may have done some of the conversion wrong so I recommend doing the conversion on your own to make sure it's right.) Then to get your answer in terms of solar mass, just convert the same way you normally would. (answer from above) x 1 solar mass/2 x 10^30 kg
For B, I haven't worked out the answer for a yet but I think all you need to do is Subtract the mass of the B2 main sequence star from the sum of the two objects (m1+m2).
I hope this was helpful!
MESSAGE #141. Sun Apr 11 2:08:58 2010. Barak Taragin wrote:
MESSAGE #140. Sun Apr 11 1:24:02 2010. Barak Taragin wrote:
MESSAGE #139. Sat Apr 10 21:35:10 2010. Barak Taragin wrote:
MESSAGE #138. Sat Apr 10 20:38:17 2010. Emma Witkowski wrote:
Emma
MESSAGE #137. Sat Apr 10 20:29:07 2010. Emma Witkowski wrote:
Thanks, Emma
MESSAGE #136. Fri Apr 9 20:31:59 2010. Patrick Barry wrote:
http://www.msnbc.msn.com/id/36286975/ns/technology_and_science-space/
MESSAGE #135. Fri Apr 9 11:47:47 2010. Joseph Benik wrote:
MESSAGE #134. Fri Apr 9 11:38:34 2010. Barak Taragin wrote:
MESSAGE #133. Tue Apr 6 23:59:15 2010. Nechama Yagod wrote:
MESSAGE #132. Fri Apr 2 14:29:35 2010. Yevgeny Deviatov wrote:
I just saw that on Digg, was about to post that. lol.
MESSAGE #131. Fri Apr 2 11:36:27 2010. Seaver Li wrote:
http://www.newscientist.com/article/mg20527522.900-neptune-may-have-eaten-a-planet-and-stolen-its-moon.html?DCMP=NLC-nletter&nsref=mg20527522.900
MESSAGE #130. Tue Mar 30 21:39:13 2010. Maria Chang wrote:
Thanks!
Maria
MESSAGE #129. Tue Mar 30 19:25:17 2010. Tyler Ross wrote:
Interesting FAQ regarding blackholes, easy to follow links. I could not wait for us to cover them in class so I went ahead and did some of my own research.
MESSAGE #128. Tue Mar 30 0:06:38 2010. James Kastner wrote:
This video from Dr. Michio Kaku is very interesting, as are his other videos. He talks about physics in a way that is simple and relates concepts to the common man. Very interesting person to watch.
MESSAGE #127. Mon Mar 29 22:05:02 2010. Erin Kisliuk wrote:
Does anyone understand Chapter 8 number 21? I don't really know how they want us to use the units or the conversions to answer the questions.
MESSAGE #126. Mon Mar 29 20:11:31 2010. Lahiru Aluthgama G wrote:
http://www.ted.com/index.php/talks/brian_greene_on_string_theory.html
MESSAGE #125. Sun Mar 28 13:23:44 2010. Abinet Aklilu wrote:
Here's an article that talks about recent extrasolar planet discoveries made by the Kepler mission. The Kepler telescope was launched on March 7, 2009 to hunt for extrasolar planets. It detects the change in the brightness of a star as a planet transits it. This is the indirect technique of detecting extrasolar planets Professor Hamilton taught us on Tues. This technique is also discussed in Ch.7 of our text book.
Here's the link to the article: http://www.usnews.com/science/articles/2010/01/04/space-telescope-finds-its-first-extrasolar-planets.html
Enjoy! -Abinet
MESSAGE #124. Sat Mar 27 22:51:43 2010. Prof. Doug Hamilton wrote:
Please welcome our two new ASTR100 TAs! Lauren Woolsey will be taking over sections 0101 (Wed. 1:00-1:50) and James Keane will take 0103 (Friday 10:00-10:50). James will preside over extended Friday office hours (11-2) and Lauren will open up a Monday 6-8pm slot for all you homework procrastinators! The new office hours begin Monday March 29. Enjoy!
DH
MESSAGE #123. Sat Mar 27 22:07:10 2010. Clayton Aptekar wrote:
MESSAGE #122. Fri Mar 26 13:28:11 2010. Alex Kavalsky wrote:
MESSAGE #121. Fri Mar 26 1:21:28 2010. Shaun Morris wrote:
MESSAGE #120. Thu Mar 25 12:26:58 2010. Benjamin Park wrote:
http://news.yahoo.com/s/space/20100324/sc_space/lastchancetogetagoodlookatmarsuntil2012
MESSAGE #119. Tue Mar 23 9:21:59 2010. Michael Sullivan wrote:
http://www.dailymail.co.uk/sciencetech/article-1259813/Mars-Ice-walls-Red-Planet.html
MESSAGE #118. Fri Mar 19 10:12:28 2010. Lahiru Aluthgama G wrote:
Ok this is kind of cool. Apparently some team of astronauts in Russia is trying to simulate a manned mission to Mars here on Earth. The mission is called Mars 500 because that's how many days they would have to stay locked in that capsule until they reach Mars.
http://www.good.is/post/mars-500-training-astronauts-for-a-manned-mission-to-mars?GT1=48001
MESSAGE #117. Thu Mar 18 13:03:26 2010. Michael Kattouf wrote:
"Some experts point out that natural cycles in Earth's orbit can alter the planet's exposure to sunlight, which may explain the current trend. Earth has indeed experienced warming and cooling cycles roughly every hundred thousand years due to these orbital shifts, but such changes have occurred over the span of several centuries. Today's changes have taken place over the past hundred years or less." - http://news.nationalgeographic.com/news/2004/12/1206_041206_global_warming.html
http://www.epa.gov/climatechange/
MESSAGE #116. Wed Mar 17 20:11:33 2010. Leah Loreman wrote:
MESSAGE #115. Wed Mar 17 3:28:21 2010. Michael Kattouf wrote:
http://arstechnica.com/science/news/2010/03/general-relativity-passes-a-large-scale-test.ars
MESSAGE #114. Wed Mar 17 3:27:46 2010. Michael Kattouf wrote:
MESSAGE #113. Wed Mar 17 3:00:51 2010. Michael Kattouf wrote:
http://news.bbc.co.uk/2/hi/science/nature/8556621.stm
MESSAGE #112. Sun Mar 14 8:56:30 2010. Prof. Doug Hamilton wrote:
Sounds like an interesting movie! It turns out that the Sun will go into the red giant phase while it still has plenty of Hydrogen fuel left - the problem is all of the H is away from the center where it is too cool to fuse! This happens because the heavier Helium sinks to the center and displaces the lighter H (similar to the formation of Earth's iron core). A huge bomb might initiate some fusion, but only temporarily.
To really fix the Sun, all we would have to do is remove the Helium center! Then the H would flow into the center, heat up and fuse, and all would be well. In the future, such operations may become routine and the stellar patients might be expected to fully recover and go on with their shiny happy lives.
DH
MESSAGE #111. Sat Mar 13 13:16:35 2010. Joseph Pierro wrote:
http://news.yahoo.com/s/space/20100312/sc_space/lifeenablingmoleculesspottedinorionnebula
MESSAGE #110. Fri Mar 12 16:44:06 2010. Elliot Wertheim wrote:
One of my favorite "you probably haven't heard of it" movies is Sunshine. It came out in 2007 to a lukewarm critical reception. The plot of the movie is fairly simple. At some point in the future, our sun is dying out. The people of the Earth decide to send a spacecraft to the sun, in order to "jumpstart" its fusion process. Their idea is setting off a massive bomb in the sun, creating a "sun within a sun". My question is this: Assuming some massive technology improvements, is this at all realistic? Could a new star be created directly out of the fading remnants of its predecessor?
Anyway, this question aside, its a really good movie. Good acting, dialogue, some action/love story. Great stuff.
MESSAGE #109. Thu Mar 11 10:28:09 2010. William Schenk wrote:
PopSci article on NASA finding tons of lunar ice!
MESSAGE #108. Thu Mar 11 5:23:59 2010. Prof. Doug Hamilton wrote:
For Kaye's question, it is too late for Venus! If we could move it to where Mars is (and maybe make Mars its moon!) Venus would still remain far hotter than the Earth due to its massive atmosphere of the greenhouse gas CO2. Remember from class that Venus probably once has a global ocean like Earth and that the evaporated water from this ocean acted as a greenhouse gas, raising the planet's temperature and ultimately evaporating its entire ocean into a steam atmosphere. Over millions of years, the H from H2O were lost to space, while the O combined with rocks to form CO2. Today, there is as much O in CO2 in Venus' atmosphere as there is O in Earth's H2O oceans, which is strong evidence for this past history. Since the H is gone, Venus' CO2 cannot turn back into water, even if we able to lower its temperature. Poor Venus! If we'd only thought to move it 4 billion years ago before it had lost its oceans, then it might have been habitable today!
MESSAGE #107. Thu Mar 11 1:31:27 2010. Garrett Kemp wrote:
MESSAGE #106. Wed Mar 10 20:49:58 2010. John Connor wrote:
MESSAGE #105. Wed Mar 10 18:25:54 2010. Daniel Sullivan wrote:
MESSAGE #104. Wed Mar 10 17:58:16 2010. Alex Kavalsky wrote:
MESSAGE #103. Wed Mar 10 17:43:50 2010. Daniel Sullivan wrote:
MESSAGE #102. Wed Mar 10 17:36:22 2010. Kaye Gilchrist wrote:
MESSAGE #101. Wed Mar 10 16:47:48 2010. Christine Hylind wrote:
Christine Hylind
MESSAGE #100. Wed Mar 10 12:50:27 2010. Emma Witkowski wrote:
This is a really intersting article I found while researching geology for Chapter 5. It discusses the threat of methane, a more powerful greenhouse gas than carbon dioxide. As the arctic is continuously rising in temperature it vent more and more amounts of methane. It was a good read, never thought about yet another, more dangerous possible threat to our environment.
MESSAGE #99. Wed Mar 10 11:45:15 2010. Cameryn Mann wrote:
MESSAGE #98. Wed Mar 10 6:35:06 2010. Prof. Doug Hamilton wrote:
MESSAGE #97. Mon Mar 8 21:36:59 2010. Joseph Benik wrote:
MESSAGE #96. Mon Mar 8 20:55:23 2010. Tina Nguyen wrote:
MESSAGE #95. Mon Mar 8 12:46:28 2010. Benjamin Park wrote:
This is an interesting article about Dark matter. Hope we talk about this at one point during the semester.
MESSAGE #94. Mon Mar 8 8:34:03 2010. Joseph Benik wrote:
Scientists reaffirm theory that giant asteroid killed dinosaurs
MESSAGE #93. Sun Mar 7 9:52:00 2010. Jordan Hansbrough wrote:
MESSAGE #92. Sat Mar 6 21:48:10 2010. Alex Kavalsky wrote:
MESSAGE #91. Sat Mar 6 21:17:20 2010. Clayton Aptekar wrote:
Interesting article on glaciers on Mars
MESSAGE #90. Sat Mar 6 16:29:49 2010. Prof. Doug Hamilton wrote:
This is an issue where the wide range of math backgrounds in our class of 240 students comes into play. For many of you, the math problem on the exam is trivial and can easily be done in your head. For many others, however, the problem is the most difficult one on the exam. More people than you might expect didn't even attempt it.
All or nothing grading based on getting the right answer would have allowed us to grade much faster, but would have penalized students who made "small" errors. Seeing the work allows us to separate small errors from large ones and grade accordingly. Although this takes more time, it is our way of trying to be fair to all students. Those of you smart enough to do the math problem in your heads should also be smart enough to put down a few of the intermediate steps!
There will be more problems like this on the next midterm and on the final exam, so it worth having this discussion now!
DH
MESSAGE #87. Fri Mar 5 22:18:56 2010. Connor Brooks wrote:
It may be just my personal opinion, but when I read the question I instantly knew the answer, did it in my head and wrote it in sentence format because I understood the equation. Please correct me if I am wrong, but is that not the point of the question and the test in general? This is especially true when you consider how unlikely it would be for someone to randomly guess the answer, on top of which considering they couldn't have taken it from a neighbor who would have had a different version of the test. In fact I would consider it easier for someone to accidentally get the right answer when they didn't previously understand the equation by working it out on paper than by randomly guessing. I guess I'm just ranting at this point, but if you could shed a little more light on this for me, I would appreciate it. Thanks.
MESSAGE #86. Fri Mar 5 19:51:53 2010. Prof. Doug Hamilton wrote:
To make it up to you, I'm going to offer 2 more bonus points for March Blog Posts! (I've never done that before). There will also be bonus points for filling out the mid-course evaluation form that I will point you toward next week.
On another note, the TAs suggested that I move forward the deadline for homework #3 from Tuesday to Thursday next week. I was initially reluctant, but do think that it is the right thing to do given that we are still behind because of the snow days. So HW#3 is now due on Thursday!! ASTR100 Blog Readers are always the first to know! Please help spread the word - I'll also send out a general email to the class soon. But be sure to start the HW early and make use of office hours next week if you get stuck!
MESSAGE #85. Thu Mar 4 19:28:49 2010. Dummea Kumahle-Vincent wrote:
MESSAGE #84. Wed Mar 3 20:48:24 2010. Emily Perry wrote:
MESSAGE #83. Wed Mar 3 20:17:21 2010. Justin Chang wrote:
MESSAGE #82. Tue Mar 2 22:16:45 2010. Joseph Benik wrote:
My pts for the syllabus sheet showed up weeks ago. I think they were the first thing professor Hamilton posted.
MESSAGE #81. Tue Mar 2 21:28:18 2010. Daniel Martinez wrote:
MESSAGE #80. Tue Mar 2 13:31:37 2010. Yevgeny Deviatov wrote:
http://www.space.com/scienceastronomy/water-moon-north-pole-100301.html
MESSAGE #79. Tue Mar 2 12:10:03 2010. Kevin McCabe wrote:
http://news.yahoo.com/s/space/20100302/sc_space/chileearthquakemayhaveshorteneddaysonearth
MESSAGE #78. Mon Mar 1 23:12:46 2010. Christopher Caruso wrote:
MESSAGE #77. Mon Mar 1 22:09:42 2010. Aaron Czinn wrote:
http://eclipse.gsfc.nasa.gov/eclipse.html
MESSAGE #76. Mon Mar 1 21:03:38 2010. Uzodinma Ihekwoaba wrote:
MESSAGE #75. Mon Mar 1 14:16:07 2010. Najma Knobloch wrote:
MESSAGE #74. Sun Feb 28 18:18:49 2010. Carol Downey wrote:
MESSAGE #73. Sat Feb 27 14:40:04 2010. Mario Pareja-Lecaros wrote:
MESSAGE #72. Thu Feb 25 19:02:21 2010. Leah Loreman wrote:
Also if anyone would want to get together to study Monday anytime before 1 on or off campus maybe for brunch/lunch (I'm a commuter, so sometimes thats easier) please email me! lmloreman@gmail.com
Thanks!
MESSAGE #71. Thu Feb 25 6:57:35 2010. Prof. Doug Hamilton wrote:
ASTR100 Exam I is on Tuesday! My exams are difficult, so get some study time in as soon as you can. I've just posted an Exam I review sheet off the "Assignments" link which gives some details of the exam, some general advice, and a list of topics that it would be wise to know something about.
Good Luck!
MESSAGE #70. Tue Feb 23 21:54:14 2010. Prof. Doug Hamilton wrote:
I am also writing to wind up the HW#1 saga. Most to you who have written have worried about working together. Again, this is one of the best ways to learn and we encourage it. Just don't cross the line into copying. As we discussed in class, one sentence duplicated on two papers is almost always enough for the honors council to find both parties "Responsible".
A lot of you wrote to me, mostly with situation that I could not check - I didn't answer emails where I had nothing that I could say. I did answer most of you who gave me enough detail to spot check HW papers and most of those were fine. If you've not heard from me, relax you're HW#1 will not be further investigated. I still need to meet with a handful of students, but those students should all have received emails from me at this point.
So let's hope for a clean HW#2 and Exam I!
MESSAGE #69. Tue Feb 23 11:20:43 2010. Garrett Kemp wrote:
MESSAGE #68. Tue Feb 23 0:13:12 2010. Kelly Klein wrote:
MESSAGE #67. Mon Feb 22 23:19:32 2010. Abinet Aklilu wrote:
Here is an interesting article about a meteorite found in Canada. The scientists say it's even older than the Sun.
http://www.guardian.co.uk/science/2006/dec/01/uknews
-Abinet
MESSAGE #66. Mon Feb 22 21:11:18 2010. John Connor wrote:
MESSAGE #65. Mon Feb 22 21:05:18 2010. Prof. Doug Hamilton wrote:
By the same token, I would encourage Kaye and others to keep an open mind and not be so quick to disbelieve the hypothesis. The time to judge the hypothesis is after we've seen evidence that might support or refute it.
So come to class tomorrow and we'll go to it!
MESSAGE #64. Mon Feb 22 19:14:05 2010. Eytan Hirsch wrote:
http://hubblesite.org/explore_astronomy/black_holes/
MESSAGE #63. Mon Feb 22 18:57:00 2010. Jordan Kamzan wrote:
http://www.nasa.gov/externalflash/50th/main.html
MESSAGE #62. Mon Feb 22 17:35:18 2010. Kaye Gilchrist wrote:
MESSAGE #61. Sun Feb 21 20:19:11 2010. Barak Taragin wrote:
MESSAGE #60. Sun Feb 21 14:03:30 2010. Prof. Doug Hamilton wrote:
i) I am fear-mongering the class
ii) These issues should be handled privately not publicly.
There is some truth to these claims so let me respond here.
i) First, I am trying to scare the class. It is a very serious problem when there are already cheating cases on HW#1 - especially after all of the up front warnings. I want you all to be aware of where the line for cheating lies and to be well to the right side of that line. If the level to which this issue has risen prompts you to be more careful, that is probably a good thing.
Second, the comment from my class email: "If you do not, no mercy - you'll get the hammer without the lead brick." is perhaps too colorful. What that means is "If you do not, no mercy - I will refer your case to the honor council.", just as it states in the class syllabus. My role is to determine whether or not a given instance of suspected academic dishonesty is serious enough to be forwarded to the honor council.
ii) As for pubic vs. private, I am going to back off from my request for "apology posts" to this site. From the wording of the relevant posts, it is impossible to tell whether I have scared people who are innocent of all wrongdoing or whether there is something more going on. I do, however, admire people who have the moral courage to admit when they have made a mistake. For this reason, I will still accept these sorts of messages, but to my private email rather than to this site.
I'll end with a qualified apology to those who have posted here, or written to me directly, or thought about doing one of these things regarding HW#1. If you are innocent of wrongdoing, I am sorry for having stressed you out.
DH
MESSAGE #59. Sun Feb 21 13:16:07 2010. Anonymous3 wrote:
After reading Anonymous1 and Anonymous2 comments as well as Professor Hamilton's, I would like to say that I too worked with a classmate on the homework because several of the problems were difficult to us. We collaborated on the work together, just like Anonymous2 and Anonymous1. I apologize if my work appeared to be plagiarized because all with the exception of the math problems were done solo. I, like Anonymous2, hope that this did not violate the code of conduct and if so hope that I will be forgiven.
-Anonymous3
MESSAGE #58. Sun Feb 21 11:01:29 2010. Bryan Miller wrote:
http://www.valdosta.edu/~cbarnbau/astro_demos/
MESSAGE #57. Sat Feb 20 20:55:04 2010. Anonymous2 wrote:
My post is in response to the previous post made by Professor Hamilton. Over this past week, a classmate and I got together because he was slightly confused about some of the math involved on the homework. We met in McKeldin Library so we could collaborate on some of the problems that gave him trouble (and one in particular that confused me.) My situation is basically identical to Anonymous1's: I worked together on the homework with friends. I feel much better after reading the professor's post because he encourages us to work together, but I just wanted to get it off my chest and make sure that what I did was not a violation of the code. I apologize if I did violate the code. It was definitely unintentional. I know how hard the class works on the homework and I would hate to undermine their hard work.
Best,
Anonymous2
MESSAGE #56. Sat Feb 20 19:29:23 2010. Prof. Doug Hamilton wrote:
What Anonymous1 wrote today took courage, especially since she didn't (and still doesn't) know whether or not she is on my cheater list. She deserves credit for her bravery.
To clarify one of her points, I don't expect you to go solo on the ASTR HW assignments - working with friends is one of the best ways to learn! The problems are not easy, and I encourage you to teach others, learn from others, and work together in groups. Working together, however, does cross the line into academic dishonesty when direct copying (from the book, from another source, or from each other) occurs. That is plagiarism.
If one student copies from another, both are guilty of academic dishonesty. The student who allows his/her paper to be copied has facilitated academic dishonesty which is also against the student honor code.
I know that there are more of you out there with guilty consciences. Follow Anonymous1's lead and 'fess up on this blog. Partial pardons are available until 9am Tuesday.
DH
MESSAGE #55. Sat Feb 20 17:20:32 2010. Leah Loreman wrote:
MESSAGE #54. Sat Feb 20 17:18:48 2010. Leah Loreman wrote:
For the second extra credit question...there isn't really a question? What are we suppose to show you to show we did/understand it?
MESSAGE #53. Sat Feb 20 12:34:17 2010. Anonymous1 wrote:
On homework number one i dishonestly worked with two friends by doing the assignment together. This was a homework meant to be done on our own so by doing this, I gave myself an unfair advantage over the rest of my classmates. My reason for doing so was out of insecurity that I would not be capable to get the correct answers on my own and feared ruining my grade by messing up the first homework assignment although I did contribute and work hard. None the less, I am sorry for being dishonest and not doing this work on my own. I have learned my lesson and now understand that it is important not only for the moral of honesty but for my own good that I do the assignments on my own in the future so that I 1.) better absorb the information, and 2.) do not give myself an upper hand over everyone else who may have been in a similar predicament. This will not happen again and instead next time I will seek guidance from a TA if I am feeling lost with the information.
I am truly sorry and hope I can be forgiven, Anonymous1
MESSAGE #52. Fri Feb 19 10:20:16 2010. Clayton Aptekar wrote:
http://www.facebook.com/pages/College-Park-MD/UM-Observatory/21259379814
MESSAGE #51. Fri Feb 19 10:04:25 2010. Christine Hylind wrote:
MESSAGE #50. Fri Feb 19 9:34:07 2010. Tina Nguyen wrote:
MESSAGE #49. Fri Feb 19 5:57:43 2010. James Kastner wrote:
Also, excuse the blank post I made below, I've never used this blog system before and pressed the wrong button.
Thanks.
MESSAGE #48. Fri Feb 19 5:52:41 2010. James Kastner wrote:
MESSAGE #47. Thu Feb 18 22:25:09 2010. Emma Witkowski wrote:
so if anyone could send the notes I would really appreciate it!
ewitkows@umd.edu
MESSAGE #46. Thu Feb 18 20:35:30 2010. Andrew Connelly wrote:
MESSAGE #45. Thu Feb 18 20:24:32 2010. Clayton Aptekar wrote:
An incredible article on the debate of the dwarf planet title of Pluto.
MESSAGE #44. Thu Feb 18 19:42:08 2010. Benjamin Park wrote:
http://news.yahoo.com/s/afp/20100218/sc_afp/scienceastronomysupernova_20100218083221
MESSAGE #43. Thu Feb 18 19:40:46 2010. Prof. Doug Hamilton wrote:
The Solutions for HW#1 are now posted on the Assignments link of the class website. Take a look to get a sense of what we are looking for before you get too deep into HW#2! Meet up with others and/or take advantage of office hours if you get stuck.
The ASTR100 policy for recovering from the snow days is to keep all of our assignments and tests on track. This will require more effort from you all, especially for HW#2, as we will have less lecture and section support for this assignment. Again, I encourage you to take advantage of office hours - I moved mine to Monday 10-12 next week to better support HW#2.
Finally, I am concerned about the cheating cases that I just emailed you all about. A cheater attempts to make himself or herself look better that he or she is and does so to the detriment of the rest of the class. It is exactly analogous to someone who cheats on his/her taxes with the result that every one else's taxes rise slightly. The honest students in ASTR100 are the victims here! For this reason, I've asked the cheaters to apologize to the class on this blog. We'll see what happens.
DH
MESSAGE #42. Thu Feb 18 19:31:54 2010. Najma Knobloch wrote:
MESSAGE #41. Thu Feb 18 19:27:22 2010. Tina Nguyen wrote:
MESSAGE #40. Thu Feb 18 19:16:42 2010. Joseph Benik wrote:
v = d / t
velocity equals distance over time
MESSAGE #39. Thu Feb 18 18:47:46 2010. Emily Perry wrote:
Im a bit confused on question 21 for chapter 4. Is there a common sense equation that I should know about?
I apreciate your responses
MESSAGE #38. Thu Feb 18 16:13:02 2010. Emma Witkowski wrote:
ewitkow@umd.edu
It would be much appreciated! Thanks, Emma Witkowski
MESSAGE #37. Wed Feb 17 16:25:39 2010. Joseph Benik wrote:
On the left side click Kepler's Second Law. Then click the checkbox for "sweep continuously" and the "Start sweeping" button
You can fiddle with the semi-major axis and eccentricity and see how it affects the swept out portions.
MESSAGE #36. Wed Feb 17 11:27:05 2010. Angelleda Dilts wrote:
MESSAGE #35. Wed Feb 17 11:26:11 2010. Angelleda Dilts wrote:
MESSAGE #34. Tue Feb 16 23:27:18 2010. Leah Loreman wrote:
MESSAGE #33. Tue Feb 16 0:33:07 2010. Yevgeny Deviatov wrote:
MESSAGE #32. Mon Feb 15 21:45:27 2010. Abinet Aklilu wrote:
Here’s another great source on our solar system. It also has some very interesting basic clear and concise information about comets, asteroids, dwarf planets and satellites. It covers topics such as the composition of the planets, size and distance comparison, how our solar system was formed and other solar systems.
http://www.nasa.gov/worldbook/solarsystem_worldbook_update.html
There are also some great images with good descriptions on the NASA website (at the following link)—if anyone is interested:
http://www.nasa.gov/multimedia/imagegallery/iotd.html
-Abinet.
MESSAGE #31. Mon Feb 15 19:51:05 2010. Melinda Brennan wrote:
There was a pretty cool article in the Diamondback today about an Astronomy professor here at UMD who has been doing research about the effects of asteriods smashing into the earth and how we still don't have a plan for what we would do about an Armageddon-sized one. Just thought it was interesting anod you guys would like it :)
http://www.diamondbackonline.com/news/trying-to-stop-the-big-smash-1.1158550
MESSAGE #30. Mon Feb 15 17:51:52 2010. Matthew Marquis wrote:
Does anyobody have the ASTR book that lives in Allegany hall or near it? If so could i use it tonight to finish the homework. There are no more copies at the bookstore. I would appreciate your help.
thanks.
MESSAGE #29. Thu Feb 11 17:02:48 2010. Tina Ching wrote:
http://www.cnn.com/2010/TRAVEL/02/05/easter.island.travel/index.html
enjoy =]
MESSAGE #28. Wed Feb 10 15:38:11 2010. Daniel Martinez wrote:
MESSAGE #27. Tue Feb 9 16:20:01 2010. Joseph Benik wrote:
22 i couldn't have figured this problem out myself but our TA in discussion section did a similar problem and gave us the relevant equations. visual the orbit as a circle and calculate its circumference as distance. c = pi * 2r
calculating for velocity v = d/t
MESSAGE #26. Tue Feb 9 15:33:45 2010. Kaye Gilchrist wrote:
MESSAGE #25. Tue Feb 9 12:49:08 2010. Leah Loreman wrote:
MESSAGE #24. Mon Feb 8 21:55:11 2010. Prof. Doug Hamilton wrote:
Jordan - correctness! I'm not interested in whether you can fill pages of paper with writing, I'm interested in whether you understand astronomy!
MESSAGE #23. Sun Feb 7 17:37:04 2010. Jordan Kamzan wrote:
MESSAGE #22. Sat Feb 6 23:04:29 2010. Jeremiah Van Rossum wrote:
Global warming, or climate change, is caused primarily by an increase in the amount of green house gases, such as carbon dioxide, in the atmosphere. To give you an idea of how strong the affect is just take a look at the surface temperatures of Mercury and Venus compared to their distances from the Sun. Venus is about 50 million kilometers farther away from the Sun yet has an average surface temperature that's 15 degrees celsius hotter. The numbers aren't exact but you get the idea. The thicker atmosphere traps more energy from the Sun instead of reflecting it off into space.
Jeremiah
http://www.nasa.gov/worldbook/venus_worldbook.html http://www.nasa.gov/worldbook/mercury_worldbook.html
MESSAGE #21. Sat Feb 6 14:53:12 2010. Daniel Martinez wrote:
MESSAGE #20. Fri Feb 5 20:36:42 2010. Dummea Kumahle-Vincent wrote:
MESSAGE #19. Fri Feb 5 19:52:41 2010. Jeremiah Van Rossum wrote:
MESSAGE #18. Fri Feb 5 18:41:15 2010. Joseph Benik wrote:
MESSAGE #17. Fri Feb 5 12:55:46 2010. Leah Loreman wrote:
MESSAGE #16. Fri Feb 5 11:32:13 2010. Ivan Lochan wrote:
MESSAGE #15. Fri Feb 5 10:39:24 2010. Jeremiah Van Rossum wrote:
MESSAGE #14. Thu Feb 4 20:32:56 2010. Shaun Morris wrote:
MESSAGE #13. Thu Feb 4 19:27:01 2010. Elaine Park wrote:
MESSAGE #12. Wed Feb 3 22:36:56 2010. Prof. Doug Hamilton wrote:
I'd recommend skipping the Open House on Friday if it is snowing! :)
MESSAGE #11. Wed Feb 3 21:04:55 2010. Christine Hylind wrote:
Check it out, it's pretty helpful!
MESSAGE #10. Wed Feb 3 20:28:08 2010. Megan Kowalski wrote:
http://www.youtube.com/watch?v=xwGs8_otT64
Also, I found this cool video (http://www.youtube.com/watch?v=Rk3Hjk_oHZ0&feature=fvw) that shows a lunar and solar eclipse occuring with some music in the background. It helped me visualize the different eclipses better.
MESSAGE #9. Wed Feb 3 20:19:58 2010. Maria Chang wrote:
Specifically, there's a comic about the scale (logarithmically) of the observable universe, with some unexpected objects too. Not necessarily 100% accurate, but entertaining nonetheless. The Observable Universe, from top to bottom
Enjoy!
MESSAGE #8. Wed Feb 3 16:05:09 2010. Joseph Benik wrote:
MESSAGE #7. Wed Feb 3 12:47:51 2010. Alex Kavalsky wrote:
If you want to read up on it, here's the article I found.
MESSAGE #6. Tue Feb 2 22:52:27 2010. Nathan Calcagni wrote:
MESSAGE #5. Tue Feb 2 18:07:11 2010. Elliot Wertheim wrote:
http://www.youtube.com/watch?v=Q4_7OsKLkGw&feature=player_embedded#
MESSAGE #4. Tue Feb 2 17:10:45 2010. Laura Miles wrote:
It's a link to the Astronomy Magazine's online page... specifically the link to information about the sky this month (so obviously it changes each month.) It's really cool though!
Keep this in mind: "Several major planets, and at least one minor one (the asteroid Vesta), give solar system observers plenty of targets for a night under the stars. The two brightest objects — Venus and Jupiter — pass close to each other low in evening twilight in mid-February."
MESSAGE #3. Tue Feb 2 16:22:04 2010. Boban Dedovic wrote:
Thus far in ASTR100, I have learned many things that have been both new and interesting. While I knew that light took a long time to travel, I never knew that looking into outer space gave us such insight as to see into the past. This explains how scientists and physicists study the stars with a certain degree of certainty.
Moreover, I was intrigued to find out that the universe is truly that grand and massive. WHile here on earth we can easily comprehend the size of a basketball or even a building, I still find it difficult to realize that our planet alone is over 24,000 miles across the equator and orbiting at a speed of more than 100,000 km/hr.
Finally, as Dr. Hamilton outlined it is important for us to distinguish between a solar system and galaxy; therefore, I will provide a clear explanation: A solar system is a collection of objects orbiting around a single star, like our sun and the 8 (or 9?) planets while a galaxy is a collection of stars in space that contains millions/trillions of them in a disc shape like the milky way.
Sincerely, Boban Dedovic TueThu 9:30 - 10:45, section 0101 Brian Knesel
MESSAGE #2. Tue Feb 2 6:40:03 2010. Prof. Doug Hamilton wrote:
MESSAGE #1. Mon Jan 25 21:59:32 2010. Prof. Doug Hamilton wrote:
But Wait - there's More! Simply post something fun here by February 28 and receive 2 juicy bonus points!*
* Offer void where prohibited by law, you must be enrolled in ASTR100 to participate, you must be a resident of Earth, and bonus points have no cash value.