Longmont Astronomical Society Newsletter. Image Credit: Chris Fauble

Image Credit: Chris Fauble Longmont Astronomical Society Newsletter April 2016

Next LAS Meeting April 21 st Time-Domain Astronomy and Las Cumbres Observatory Global Telescope by Dr. Tim Brown Abstract: Astronomer's view of the universe is changing from seeing the sky as unchanging "wallpaper", to a dynamic picture in which everything changes, all the time. More, we are realizing that the ways in which things change often give us clues to the physics of astronomical objects that we could not obtain otherwise. The buzzword for this view is "time-domain astronomy", and its hardware manifestations range from the 8-meter Large Synoptic Survey Telescope (LSST), down through the Kepler Mission's 1-meter space telescope, to 30-cm backyard telescopes run by enthusiastic amateurs. In the middle of this range is Las Cumbres Observatory Global Telescope (LCOGT), so far the only observatory dedicated exclusively to the general field of time-domain astronomy, and equipped to observe many kinds of time-varying phenomena. LCOGT operates a worldwide network of telescopes with apertures from 40 cm to 2 meters, working on programs that include extrasolar planets, supernovae, near Earth asteroids, and active galactic nuclei. Location: The meeting will be at the IHOP Restaurant, 2040 Ken Pratt Boulevard, Longmont. Please join us for coffee, dinner, or just desert around 6 pm; The general meeting and presentation will begin at 7 pm. Upcoming Events April 15 th 8 pm Imagine Charter School 6 th Grade Star Party, 1573 Twilight Ave, Firestone, CO. April 16 th 8:30 pm Majestic View Nature Center 7030 Garrison St, Arvada, CO April 21 st 7 pm LAS Meeting "Time- Domain Astronomy and Las Cumbres Observatory Global Telescope" by Dr. Tim Brown at IHop Restaurant, 2040 Ken Pratt Boulevard, Longmont. May 19 th 2016-7 pm LAS Meeting NASA s Messenger Mission by Dr. Dan Baker at IHOP Restaurant, 2040 Ken Pratt Boulevard, Longmont. I will briefly review the history of observational astronomy (and show that observing the time domain is getting back to old roots), and then describe LCOGT's origins and facilities, ending with some highlights of the science that LCOGT scientists are now doing. Page 1 Copyright April 2016. All rights reserved. Longmont Astronomical Society.

April Celestial Highlights Jupiter Moon New moon: April 6 th 5:52 am First quarter: April 13 th 10:01 pm Full moon: April 21 st 11:25 pm Third quarter: April 29 th 9:30 pm Mercury Mercury is visible in the evening sky from April 2 nd throughout the rest of the month. It begins the month at -1.5 magnitude in brightness and slowly fades to magnitude +2.9 by the end of the month. It may be viewed about an hour after sunset very low in the west. Venus Venus is not visible this month. Mars Jupiter opposition was on March 8 but it still is fabulous month to view Jupiter. It is up high and convenient to view in the evenings. Shadows from Jupiter moons Io and Europa are visible on the disk at the same this month April 5 from 2:18 am to 3:41 am. Both Io and Europa shadows may be seen transiting from 3:37 am to 4:19 am. So from 3:37 to 3:41 am you can see both moons and their shadows transiting. Mars begins the month with an apparent brightness of -0.5 and is 12 arc sec across. At the end of the month it will be magnitude -1.5 and will be 16 arc sec across. Mars opposition will be on May 22 nd. Assuming the longitude of the Great Red Spot is 241.3 it may be seen at mid transit at the following times this month: Apr 1 3:57 am alt 23 Apr 2 11:49 pm alt 58 Apr 5 1:27 am alt 47 Apr 5 9:18 pm alt 51 Apr 7 3:05 am alt 28 Apr 7 10:56 pm alt 59 Apr 10 12:35 am alt 51 Apr 10 8:26 pm alt 46 Apr 12 10:04 pm alt 58 Apr 14 11:43 pm alt 55 Apr 16 1:21 am alt 40 Copyright March 2016. All rights reserved. Longmont Astronomical Society. Page 2

Apr 17 9:12 pm alt 56 Apr 18 2:59 am alt 20 Apr 22 12:29 am alt 45 Apr 23 2:08 am alt 26 Apr 24 9:59 pm alt 59 Apr 26 11:38 pm alt 50 Apr 29 9:08 pm alt 59 May 1 10:46 pm alt 54 Saturn Saturn is in lower part of the constellation Ophiuchus. It is magnitude +0.4 in brightness as month begins and +0.2 on April 30. Its disk increases from 17 arc sec across to 18 arc sec this month. Meteor Showers The Lyrids meteor shower peaks on April 21 st but since it is also full moon only the brightest will be visible. Comets Comet 252P (Linear) is visible this month in constell ation Ophiuch us. It is magnitude 5.7 in brightness and coma is 5.7 arc min across. (Image credit Gary Garzone). Uranus Uranus reappears in the morning sky after the 24 th. It is in the constellation Pisces; it is magnitude +5.9 in brightness and its disk is 3.3 arc sec across. Neptune Neptune is visible low in the morning sky in constellation Aquarius. It is magnitude 7.9 and 2.2 arc sec across. Page 3 Copyright April 2016. All rights reserved. Longmont Astronomical Society.

Comet C/2013 X1 (PANSTARRS) is visible this month in constellation Pisces. It is fairly low and dropping into evening twilight as the month progresses. It begins the month at magnitude 8.6 and brightens to 8.3 by months end. The coma diameter decreases from 4.4 arc min to 2.8 arc min. Comet C/2014 S2 (PANNSTARRS) is visible in the constellation Ursa Major. It is magnitude 9.8 in brightness and its coma is 2 arc min across. Comet C/2013 US10 (Catalina) is visible in the constellation Camelopardalis. It moves into constellation Perseus on the 16 th. As the month begins it is magnitude 8.9 in brightness and will fade to magnitude 10.7 by month end. The coma is decreases from 4.4 arc min to 2.8 arc min in diameter. (Image Credit Paul Robinson). Copyright March 2016. All rights reserved. Longmont Astronomical Society. Page 4

Overhead Sky at 9: It is a springtime galaxy bonanza in the eastern sky this month. The constellations Virgo, Coma Berenices, and Canes Venatici provide a rich assortment of the best and brightest. Messier 51 in Ursa Major is high up and always worth a look. Jupiter is now center stage for convenient early evening viewing. This page was designed for viewing like a magazine. If you are using Adobe Reader select the following menus: View->Page Display->Two Page View Also set View->Page Display->Show Cover Page in Two Page View Page 5 Copyright April 2016. All rights reserved. Longmont Astronomical Society.

30 pm April 15 It is time to take a farewell view of Messier 42, the Great Orion Nebula, before it disappears in the evening twilight next month. Be sure to check out Mercury about 45 minutes to an hour after sunset. Gemini is still high so aim your small scope or binoculars to open cluster M35. Use one of your larger scopes to view NGC2392, the Eskimo nebula also in Gemini. Copyright March 2016. All rights reserved. Longmont Astronomical Society. Page 6

LAS March 17 th meeting at IHop The meeting began at 7 pm with announcement of the agenda for the evening and upcoming star parties. project was first proposed to NASA over 15 years ago. She reviewed the mission highlights as it progressed in its journey to Pluto. She discussed some of the stunning Image credit: NASA/JHUIAPL/SwRI The guest speaker was Dr. Fran Bagenal with the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado. Her presentation was Pluto the Pugnacious Planet. Fran has been a member of New Horizons team since the images that have received and discoveries made by the team that were published a week before in Science Magazine. Pluto s upper atmosphere is much colder and way more compact than models predicted. (See Page 7 Copyright April 2016. All rights reserved. Longmont Astronomical Society.

http://science.sciencemag.org/content/3 51/6279/aad8866). Pluto s four small moons rotate rapidly and their obliquities suggest that their shapes were caused by collisions. (See http://science.sciencemag.org/content/3 51/6279/aae0030). Particle instruments aboard New Horizons indicate that the interaction region sunward of Pluto is quite small around 6 planet radii; beyond Pluto it is about 400 planet radii. (See http://science.sciencemag.org/content/3 51/6279/aad9045 ). New Horizons observations of Pluto indicated regionally diverse colors and compositions. (See http://science.sciencemag.org/content/3 51/6279/aad9189 ). Surprisingly Pluto s surface geology is active and is centered on a vast basin of thick volatile, convective ices. ( See http://science.sciencemag.org/content/3 51/6279/1284 ). Following Fran s presentation we had a short business meeting. Mike Fellows gave the monthly financial report. Vern Raben did an update on the Library Telescope Project two telescope kits were delivered to the Louisville Public Library on March 19. Planetary Image Processing Just extract the zip file to a directory on your machine. Navigate to that folder with Windows Explorer and then double click on the Autostakkert application to run it. The application will start and you first click on the 1) Open button toward the upper left. After you navigate to the folder where you stored your videos, select the video files you wish to stack. You may select multiple files and it will stack them all. The files selected should be at the same magnification, exposures, etc. Next set the following for Image Stabilization : For planets select Planet COG. For lunar and solar in which the full disk may not be see select Surface otherwise select Edge. Vern provided a brief tutorial of using the AutoStakkert application to align and stack planetary images. The application is available for download from http://www.autostakkert.com/wp/downl oad/ If planet fits entirely within the image but is not completely visible such as before opposition when a portion of the disk is dark uncheck the Copyright March 2016. All rights reserved. Longmont Astronomical Society. Page 8

portion of the disk that is not visible. Next click the Analyze button. with 2X barlow. If you end up with an image where stitches from these small alignment windows show, you just need to decrease the number of alignment points to correct. The quality of the frames in the video will be analyzed an then sorted. You may scroll through the frames by moving slider on top of the window at the right. The best quality frames are on the left so that will be used for the reference image. Now you need to set the alignment points which is done using window on the right. Adjust the Set Size slider at top so entire planet is covered (usually not necessary to change). I try to end up with 80 to about 100 alignment points, so adjust the alignment point size. Other people use only a few dozen. I usually set AP size to 25 for small relative size planet in the image, 50 for Jupiter Click on the Place Aps in Grid button. You ll end up with something like this: Page 9 Copyright April 2016. All rights reserved. Longmont Astronomical Society.

Finally, move the Alignment points window out of the way, and click the 3) Stack button. The AutoStakkert program will then process each video and create a stacked image for each. A new directory will be created under your video images source directory, named something like AS_???_Multi. The directory contains the aligned an stacked images which you may then sharpen with an application such as Registax6. I ll cover Registax6 in detail in a future tutorial. Copyright March 2016. All rights reserved. Longmont Astronomical Society. Page 10