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MESSAGE #82. Wed Dec 18 9:22:13 2013. James Hazelrig wrote:
MESSAGE #81. Sat Dec 14 20:11:18 2013. Jacob Shpiece wrote:
MESSAGE #80. Tue Dec 10 14:56:39 2013. James Hazelrig wrote:
MESSAGE #79. Thu Dec 5 12:30:19 2013. Prof. Doug Hamilton wrote:
MESSAGE #78. Mon Dec 2 11:16:06 2013. James Hazelrig wrote:
MESSAGE #77. Sun Dec 1 10:38:50 2013. Prof. Doug Hamilton wrote:
MESSAGE #76. Sun Dec 1 10:31:56 2013. Prof. Doug Hamilton wrote:
MESSAGE #75. Sat Nov 23 21:13:33 2013. James Hazelrig wrote:
MESSAGE #74. Thu Nov 21 21:01:47 2013. James Hazelrig wrote:
MESSAGE #73. Tue Nov 19 20:37:37 2013. Emily Garhart wrote:
MESSAGE #72. Thu Nov 14 14:48:03 2013. Leanne Whittemore wrote:
Hello UMD Observatory Friends (Plus lots of other folks who might be interested)!
Well, you've probably heard some of the hoopla over the months, about some comet becoming "comet of the century" or some other such hype. Well, there was a comet discovered in Sept 2012 and it is very interesting, but was not easily observable for awhile. I've been holding off from doing an observing session for two reasons: it's in the morning sky and it's been slightly dimmer than expected. However, the past 24 hours have seen some nice jumps in brightness, so we are going to try observe comet ISON tomorrow Fri 15 November before sunrise!
And as it turns out, there are actually several comets visible in the morning sky! All require binoculars or a telescope to be seen.
We will be observing from two locations, first from the observatory, then from a garage on campus!!
3am-4:30am AT THE UMD OBSERVATORY observe comets C/2013 R1 Lovejoy C/2013 V3 Nevski
We will then transition/move over to the Terrapin Trail Garage
4:45am-6:15am (or when it's too light to see) AT THE TERRAPIN TRAIL GARAGE (top level) observe comets C/2012 S1 ISON C/2012 X1 Linear 2P Encke (rises about 5:30)
MESSAGE #71. Thu Nov 7 20:22:56 2013. Mark Nellis wrote:
MESSAGE #70. Wed Nov 6 11:38:02 2013. Stephanie Pennington wrote:
MESSAGE #69. Tue Nov 5 23:48:53 2013. Ryan Felton wrote:
MESSAGE #68. Tue Nov 5 17:46:26 2013. Mahnegar Amouzegar wrote:
MESSAGE #67. Tue Nov 5 9:24:02 2013. Prof. Doug Hamilton wrote:
Mars is a difficult target and there have been lots of failed missions: wikipedia
The Indian spacecraft is safely in low Earth orbit from where it will depart toward Mars once its systems have been rechecked: news story
MESSAGE #66. Thu Oct 31 3:15:29 2013. Mahnegar Amouzegar wrote:
MESSAGE #65. Wed Oct 30 15:05:45 2013. Emily Garhart wrote:
MESSAGE #64. Mon Oct 21 7:41:14 2013. James Hazelrig wrote:
MESSAGE #63. Sun Oct 20 20:52:38 2013. Richard Yang wrote:
MESSAGE #62. Sun Oct 20 17:49:38 2013. Ajay Mysore wrote:
MESSAGE #61. Fri Oct 18 18:10:56 2013. Prof. Doug Hamilton wrote:
MESSAGE #60. Fri Oct 18 10:19:01 2013. Kaitlin Evans wrote:
MESSAGE #59. Wed Oct 16 16:25:44 2013. Leonce Ndango-Koyakosso wrote:
MESSAGE #58. Wed Oct 16 15:32:14 2013. Amanda Drazen wrote:
MESSAGE #57. Mon Oct 14 14:18:01 2013. Prof. Doug Hamilton wrote:
Midterm scores are posted ...
MESSAGE #56. Tue Oct 8 14:57:19 2013. James Hazelrig wrote:
MESSAGE #55. Mon Oct 7 0:40:41 2013. Ryan Felton wrote:
MESSAGE #54. Sun Oct 6 22:11:27 2013. Ryan Felton wrote:
MESSAGE #53. Sat Oct 5 8:02:20 2013. Asad Muhammad wrote:
MESSAGE #52. Fri Oct 4 11:58:39 2013. Prof. Doug Hamilton wrote:
MESSAGE #51. Wed Oct 2 17:07:36 2013. Mark Nellis wrote:
Consequently through a process of slowly baking of the crust this could cause a viscoelastic crust in which crustal thinning takes places cause by ductile flow in the lower portions of the crust. By the thinning of the crust this would leave a relatively thin surface area for underlying magma plumes to puncture the surface and cause the wide spread remnants of lava plains that we see today. Now assuming that the core has cooled substantially could the slow baking of the crust replace the lost heat that would have been generated by the core and "re-energize" magma pockets causing volcanism on Venus, at least on a small scale? The magma wouldn't need to be held under high temperatures to overcome the relatively thin and ductile crust. Would this type of volcanism produce primarily pancake volcanoes or dome volcanoes?
MESSAGE #50. Wed Oct 2 10:29:41 2013. Prof. Doug Hamilton wrote:
Check out Working with Equations to practice some similar problems.
MESSAGE #49. Tue Oct 1 17:28:10 2013. Kaitlin Evans wrote:
MESSAGE #48. Tue Oct 1 0:13:47 2013. Stephanie Pennington wrote:
MESSAGE #47. Mon Sep 30 22:31:31 2013. Jacob Shpiece wrote:
MESSAGE #46. Mon Sep 30 19:28:14 2013. Amanda Drazen wrote:
MESSAGE #45. Sun Sep 29 20:10:39 2013. Kyle Elliott wrote:
MESSAGE #44. Sun Sep 29 17:28:26 2013. Michael Moss wrote:
MESSAGE #43. Sun Sep 29 17:27:20 2013. Michael Moss wrote:
I think I posted this correctly..
MESSAGE #42. Sun Sep 29 15:39:33 2013. Amanda Drazen wrote:
MESSAGE #41. Sun Sep 29 0:40:47 2013. Kyle Elliott wrote:
Here's the link for it: http://phys.org/news/2013-09-radio-evidence-exotic-phenomena.html
MESSAGE #40. Sun Sep 29 0:04:51 2013. Jacob Shpiece wrote:
MESSAGE #39. Wed Sep 25 22:09:20 2013. James Hazelrig wrote:
MESSAGE #38. Wed Sep 25 15:44:14 2013. Prof. Doug Hamilton wrote:
#35: Typically we are looking for answers accurate to 2-3 decimal places. If m/M (satellite mass/planet mass) is less than a percent or so, it is safe to ignore the small mass in Kepler's third law.
#29: ASTR121 is a fun class - nobody has signed up for it yet though! If interested, you can check out the class website (mostly ready!) by simply changing "120" to "121" in the URL.
MESSAGE #37. Wed Sep 25 12:57:03 2013. Lauren Handleton wrote:
MESSAGE #36. Wed Sep 25 12:50:08 2013. Lauren Handleton wrote:
MESSAGE #35. Wed Sep 25 0:05:14 2013. James Knell wrote:
MESSAGE #34. Tue Sep 24 22:19:45 2013. Jacob Shpiece wrote:
MESSAGE #33. Tue Sep 24 22:03:09 2013. Leonce Ndango-Koyakosso wrote:
MESSAGE #32. Tue Sep 24 19:28:27 2013. Kaitlin Evans wrote:
MESSAGE #31. Tue Sep 24 16:39:35 2013. Franco Tartaglia wrote:
Just a reminder - anyone interested in the study group can email me at email@example.com.
So far I have 2 people!
MESSAGE #30. Mon Sep 23 7:53:30 2013. James Ashley wrote:
MESSAGE #29. Mon Sep 23 1:57:37 2013. James Hazelrig wrote:
MESSAGE #28. Sun Sep 22 16:48:58 2013. Leanne Whittemore wrote:
Anyways, having trouble with the problem from W4 question a about how these distances relate to Kepler's Third Law. I understand the law just not how it relates to the "lapping" of Mercury and Venus as related to the Earth. Maybe I misunderstood the first part?
MESSAGE #27. Sun Sep 22 13:10:45 2013. Prof. Doug Hamilton wrote:
Also, either two weeks before or two weeks after each lunar event is a solar eclipse (2 partial, 1 annular, 1 total) occurring in some part of the world. Can you explain why these are the only solar eclipses over the two-year period? More details on each eclipse can be found here.
And another interesting event, the autumn equinox, occurs at exactly 4:44pm today - Happy fall!
MESSAGE #26. Sun Sep 22 11:49:56 2013. Leanne Whittemore wrote:
MESSAGE #25. Sun Sep 22 11:42:23 2013. Leanne Whittemore wrote:
He also has his own website where you can contact him. http://www.patrickjmt.com
The best part? It's all FREE!
MESSAGE #24. Thu Sep 19 17:37:33 2013. Christopher Boughter wrote:
MESSAGE #23. Thu Sep 19 15:39:56 2013. Franco Tartaglia wrote:
As was evident from my past two homeworks and discussion quiz, I realize that I do not fully understand some of the questions that are asked. With that said, if anyone is interested, I will be hosting a homework study session on Saturdays (time will be decided amongst those who wish to attend). I reside at the Courtyards, which is right outside of campus near Metzerott Road.
I will make a formal announcement tomorrow in class about this. I have a dining area and living area which can sustain no more than 7 people comfortably.
Walking to campus or taking the bus (105 or Purple Line 116) would be the best way to get here. If you decide to drive, you would have to pay to park at metered spots, but parking is free at the metered spots after 4PM.
If you are interested in attending, please email me at: firstname.lastname@example.org
MESSAGE #22. Thu Sep 19 8:28:35 2013. Prof. Doug Hamilton wrote:
MESSAGE #21. Wed Sep 18 18:33:25 2013. Ryan Felton wrote:
There is really no need to use the Moon's orbital velocity and distance from Earth to solve #31. That is just extra work and doesn't fit in with the topics of chapter 3.
An approach more in line with the chapter is to consider the sidereal and synodic month and decide which one would be appropriate for the problem. You can then figure out how many degrees the Moon moves per day (a circle has 360 degrees) and then find out many degrees it moves per hour.
Hope that helps Kaitlin.
MESSAGE #20. Wed Sep 18 1:27:36 2013. Ryan Felton wrote:
For number 44, the best way I found to visualize the differences is to open power point and make two sets of moon-earth-sun groups using the shapes available from power point. (They don't need to be to scale but at least make the Sun the biggest circle and the Moon the smallest circle.) Then make a bunch of lines and connect them the way the book does in Fig 3-11. Once you do that and set up one with the Sun fairly close and another with the Sun much further it is easier to see how the size of the umbra changes.
MESSAGE #19. Tue Sep 17 22:21:35 2013. Jacob Shpiece wrote:
MESSAGE #18. Tue Sep 17 22:03:13 2013. Kaitlin Evans wrote:
I'm having trouble figuring out 31. Any hints on how to calculate the time it takes for the Moon to move through and angle equal to 0.5 degrees against the background of the stars?
MESSAGE #17. Tue Sep 17 19:57:45 2013. Emily Garhart wrote:
MESSAGE #16. Mon Sep 16 22:47:44 2013. TA: Qian Wang wrote:
Some of you didn't quite get last Friday's quiz about seasons all right - here's a video showing how Earth's tilt leads to seasons. I find this a lot more helpful than diagrams. Make sure you understand it fully - it's important!
Also, alignment of stars has no effect on seasons at all.
MESSAGE #15. Mon Sep 16 22:06:59 2013. Prof. Doug Hamilton wrote:
MESSAGE #14. Sun Sep 15 23:20:19 2013. Amanda Drazen wrote:
MESSAGE #13. Sat Sep 14 21:00:57 2013. Kaitlin Evans wrote:
MESSAGE #12. Thu Sep 12 12:53:52 2013. Prof. Doug Hamilton wrote:
MESSAGE #11. Wed Sep 11 23:26:31 2013. Victoria Martz wrote:
P.S here is a neat image of NGC2392 a planetary nebula !
MESSAGE #10. Wed Sep 11 21:59:25 2013. Leanne Whittemore wrote:
MESSAGE #9. Tue Sep 10 22:06:27 2013. Jacob Shpiece wrote:
http://www.youtube.com/watch?v=akek6cFRZfY This is the song Outward to the Edge, done by Symphony of Science, a youtube project that promotes science by taking quotes from various lectures done by notable scientists and science enthusiasts and autotuning them. This video is about human exploration of the solar system, and includes people like Neil deGrasse Tyson and Brian Cox. There are a number of other videos, many on astronomical subjects like stars, black holes, the big bang, and mars as well as other areas of science like biology.
http://www.slate.com/blogs/bad_astronomy.html This is the blog Bad Astronomy, written by a notable astronomer Phil Plait. It regularly updates with articles on a wide range of topics, that include explanations of current NASA missions (as well as other space related missions across the world), exciting new developments in astronomy or other areas of science, global climate change, as well as especially beautiful astronomical photography.
http://xkcd.com/1248/ This is one of the many astronomy related comics from the webcomic xkcd, done by Randall Munroe. The webcomic updates every Monday, Wednesday and Friday, and often includes science related humor.
http://what-if.xkcd.com/13/ Finally, this is a blog also written by Randall Munroe called What if. In it, Munroe answers bizarre science (and other) questions with surprising accuracy. He often examines the question as first posed, and then examines it in more and more extreme conditions, and the posts are often quite humorous. The link that I provided asks the question "If every person on Earth aimed a laser pointer at the Moon at the same time, would it change color?"
These are all really fun sites that have been created centered around science and astronomy. I hope you guys enjoy!
MESSAGE #8. Mon Sep 9 21:40:20 2013. Prof. Doug Hamilton wrote:
MESSAGE #7. Sat Sep 7 15:56:24 2013. Foteine Dimitracopoulos wrote:
I have a couple of links to some really cool websites:
This one takes you to a site where you can see the Sun at any interval of time you enter (try September 23, 2011) and you can move forward in any increment of time you choose. You can also make movies on this website and save them.
This one takes you to a site where you can access data from SOHO and see the activity of the Sun throughout the year starting from 1996. If you find a solar event, you can find a certain graph in which you'll be able to see a movie of that event, and see any CMEs that may have occurred on that date.
Take a look if you're interested :)
MESSAGE #6. Fri Sep 6 23:56:02 2013. Franco Tartaglia wrote:
Hope everyone got to see the LADEE launch that happened at 11:27PM!
I will post a video and picture of the launch on the UM Observatory's Facebook Page:
For those of you who don't know what LADEE is:
"NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE, pronounced like "laddie") is a robotic mission that will orbit the moon to gather detailed information about the lunar atmosphere, conditions near the surface and environmental influences on lunar dust. A thorough understanding of these characteristics will address long-standing unknowns, and help scientists understand other planetary bodies as well."
MESSAGE #5. Thu Sep 5 19:33:18 2013. Asad Muhammad wrote:
MESSAGE #4. Thu Sep 5 14:45:44 2013. Leanne Whittemore wrote:
MESSAGE #3. Wed Sep 4 21:21:19 2013. Franco Tartaglia wrote:
Bill Nye (The Science Guy!),CEO of the Planetary Society, will be preforming on "Dancing with the Stars" on September 16th. While this is unusual (and unexpected) it seems that he will go to great lengths to provide science outreach (although the implications of how he is to achieve that are unknown in this particular instance). From the article he states, "As unusual as this may seem, I believe we can broaden awareness of the Society and thereby humankind's exploration of the Cosmos one ballroom dance at a time [...]".
Also stated in the article - Buzz Aldrin did this as well three years earlier. All we need now is Neil deGrasse Tyson's participation.
[Note: I am not (and would never think of) promoting Dancing with the Stars.]
MESSAGE #2. Tue Sep 3 22:22:36 2013. Ryan Felton wrote:
MESSAGE #1. Mon Sep 2 19:58:04 2013. Prof. Doug Hamilton wrote:
* Offer void where prohibited by law, you must be enrolled in ASTR120 to participate, and bonus points have no cash value. Bonus points will be awarded in early October; please allow 6-8 additional days for delivery.