October 2015 First Light Newsletter

Transcription

1 October 2015 First Light Newsletter October, 2015 (Issue No. 135) AlachuaAstronomyClub.org North Central Florida's Amateur Astronomy Club Serving Alachua County since 1987 Astronomical League's pin for Asterism Program. Member Member Astronomical League Member NASA Night Sky Network Astronomical League's pin for the Lunar II Program.

2 NASA DSCOVR VIDEO & MOON S DARK SIDE By Dr. Howard Cohen Emeritus Associate Professor of Astronomy University of Florida Robert Munyer, AAC member, wrote a recent (2015 August 31) about the DSCOVR video (2015 August 5) showing the Moon passing in front of an illuminated (full) Earth as viewed from the DSCOVR satellite. Here, the Sun also illuminates the far side as the Moon that observers on Earth cannot see. (Note: DSCOVR s location is between Earth and Sun approximately one million miles from Earth where it can monitor the Sun s particles from the solar wind.)

3 If you have not seen this spectacular video, From a Million Miles Away, NASA Camera Shows Moon Crossing Face of Earth? Then go to Munyer s informative correctly explains the geometry of the video and includes some pertinent remarks about the Moon s dark side. Unfortunately the use of the term Moon s dark side has now become so pervasive through the media creating a universal myth that the Moon truly has a dark side. It does not. On-line news stories about this video were filled with this term. Some examples: Though the moon's so-called dark side isn't visible from Earth... CNN A satellite caught this stunning view of the Earth and the dark side of the moon from a million miles out in space... ABC Action News The dark side of the moon looks even cooler when seen crossing the Earth from a million miles away... NBC News

4 NASA's EPIC video shows dark side of the moon passing over Earth... CNET The pictures show the dark side of the moon that is never visible from Earth, fully illuminated by the sun... CBS News I could cite many more examples. The last example is striking since the article refers to the dark side yet states the dark side is fully illuminated by the sun! Confusing at best. Geek Snack even goes further stating, NASA recently managed to snap some very nice pictures of the dark side of the Moon so that we need not wonder anymore about its appearance. Apparently Geek Snack does not know that we have been photographing the far (back) side of the Moon from spacecraft since 1959 when the USSR s Lunar Probe 3 first photographed the Moon s other side. Apollo astronauts then became the first humans to view the far side and continued to photograph it. More recently, the Lunar Reconnaissance Orbiter (launched 2009) has returned high resolution images of the far side. Of course, one could argue that the term dark side of the Moon is just an original reference to just the unknown side of the Moon rather than lack of light. However, I would respond that the continued use of dark side helps propagates wrong information about the Moon to the public. Mark Twain even wrote, Everyone is a moon, and has a dark side which he never shows to anybody. (Pudd'nhead Wilson's New Calendar in Following the Equator, 1897.) Did Twain understand that the Moon does not have a dark side or was he just simply using the term to mean unknown in the sense that everyone has a personality hidden from others? Finally, some who have viewed the video have wondered why no solar eclipse happened during the passage shown in the NASA video since the Moon was between Sun and Earth. The answer is that the satellite, Moon, Earth alignment was not precise in this video. In fact, the leading edges of both Earth and Moon show a slight terminator (darkening) that illustrates this. Do not confuse the series of color fringes on the Moon s edge with the terminator in the video. These color fringes, as NASA explains, result from combining three monochromatic photos taken at different wavelengths. Then it takes about 30 seconds to combine the three monochromatic images into a color image. Both the Earth and the Moon move slightly during this time. So the color fringes are artifacts from that process Also, the Earth s image shows a faint, almost central specular reflection of the Sun. However, the reflection looks slightly off center showing the slight misalignment. The view in the video also shows how much brighter the sunlit face of Earth is compared with the Moon's sunlit (and gray) face illustrating the much greater reflectivity of Earth. The DSCOVR video prompted needed attention on space and astronomy. Unfortunately, such events also help propagate misinformation. Astronomy organizations as the AAC must be relentless in helping communicate correct information to the public. School Outreach By Mike Toomey

5 Our first evening school school star party will be for a Gainesville-area elementary school on Tuesday, October 20. We expect at least 100 students, along with parents and a few siblings. Please register for this event on the website. Your confirmation will include the location of the event as well as other set-up instructions. (You can always un-register later). In conjunction with the Community Sciences Coalition (CSC), club volunteers will be presenting one-hour programs immediately after school. Each group will consist of about twenty 4th and 5th graders. We will provide hands-on demonstrations both in- and outside the classroom. Volunteers are welcome to choose their own topic(s), bring their own show-and-tell materials, or use club materials when available. You are welcome to shadow other volunteers at these activities before diving in. Keep in mind, you do not need to possess an encyclopedic knowledge of astronomy for these activities. It's fine to say, I don't know the answer to that. It's even better to ask students what they know, and then build upon that. Our first after-school program was held at Caring & Sharing in September. We were cheerfully received by twenty enthusiastic 4th graders. Ivo Rabell offered views of the sun through a Coronado Personal Solar Telescope (PST) just before clouds rolled in. Pam Mydock and I used the balance of the hour talking about the solar system and the motions of Earth's moon, including a primer for the upcoming (now past) lunar eclipse. The students were well-informed and had lots of great questions. We will return to Caring & Sharing in the spring. Our next after-school program will be on the east-side of Gainesville on Thursday, October 22, from 3:00pm 4:00pm. As always, please register for this event on the website for complete details. Mike Toomey has served the AAC in many capacities since 1998, including President, Secretary, FirstLight Editor, Star Party Coordinator and School Outreach Coordinator. Mike resides in Gainesville and is the author of An Illustrated Guide to Macaroni Art, Part I. The Early Years: The Latins Through the Goths. Newberry Star Park By Andy Howell

6 Last month, Newberry Star Park was pressure-washed and repainted a sky-blue "charismatic sky" color using Behr Ultra Premium Plus paint. Thanks to Lisa Eager for making arrangements to hire a good painter for this work! Also last month, Newberry Star Park received new letters to replace the old plywood letters that were delaminating and losing paint. The new Gemini letters are injection-molded plastic, designed for long life in an outdoor setting. Thanks to the ever reliable JoAnn Stevener who procured the letters for Alachua Astronomy Club! Lisa Eager, Andy Howell, JoAnn Stevener, and Allen (JoAnn's spouse) are also to be thanked for mounting the new letters to the NSP building. Andy Howell is also to be thanked for all the blisters he got on his hands while dismantling the old letters. The entire project (pressure washing, painting, and letters) cost the Club approximately $750. When one considers that the NSP building is AAC's single most valuable asset, it is worth keeping in top shape for the years ahead. If you haven't seen Newberry Star Park's new look, you should definitely plan to attend the star party & outreach on October 10! Register HERE.

7 Meetings and Events Newberry Star Park Star Party and Public Outreach Saturday, Oct. 10, 7-11 p.m. Newberry Star Park NW 16th Avenue, Newberry, FL AAC Public Meeting Tuesday, Oct. 13, 2015, 7-9 p.m. Kika Silva Pla Planetarium 3000 NW 83rd Street, Building X-129 Gainesville, FL Speaker and host: James Albury, planetarium director and co-host of the TV show Star Gazers. Big Shoals State Park Saturday, Oct. 17, 2015, 5:30-11:30 p.m. Star Party and Outreach See event calendar for details and to register. New Members since August 1!

8 Stacy Dreher Sharon Gavin Tabitha Spinuzza Ann Welch In Memoriam JoAnn Stevener informed us of the sad news that James A. Quinlan passed away Sept. 10. James was a longtime AAC member who enjoyed sharing his love of astronomy with all whom he met. James was a scholarship member for 2015, and he will be greatly missed. President Andy Howell If you haven't voted yet in the NameExoWorlds contest, vote for us! VOTE HERE First Light Newsletter Editor Laura Wright The wonders of the Astronomical League Observing programs never cease to amaze and teach us about the wonderful night sky. Please check out the Asterism Program

9 Scroll down the list until you come to our entry that proposes the names Verne, Heinlein, Asimov, and Clarke for Upsilon Andromedae and its four known exoplanets. According to the International Astronomical Union (IAU), astronomy clubs and non-profits from 45 countries submitted 247 proposals. Members of the public have already cast over 300,000 votes. Winners will receive commemorative plaques and will be eligible to propose a name for a minor planet. The voting deadline is October 31, 23:59 UTC. You can vote more than once, for each electronic device you own (computer, phone, tablet, etc.) Get out there and vote! VOTE HERE - Andy Certificate. In the introduction of the observing program, Troy Stratton, the Asterism Program Chair says "asterisms are a group of stars that appear to be associated with each other, but are not. The most well known asterism is the Big Dipper which is only a small portion of the larger constellation Ursa Major. Asterisms are often named and may be composed of stars that are members of one or more constellation. There is a list of asterisms on the program page from which to observe and sketch 100 asterisms to qualify for the certificate and pin." The Lunar II Program was developed by the Astro League in response to the many avid lunar observers and their desire for a more challenging program to follow the popular Lunar Program. Find these and more Observing programs at Best regards, Laura The Night Sky this Month

10 October's Night Sky From Seasky.org October 1 - Comet C/2013 US10 Catalina. Newly discovered comet C/2013 US10 Catalina may reach naked eye visibility on October 1. The comet will continue to brighten and could reach magnitude 5 by November 6. October 8 - Draconids Meteor Shower. The Draconids is a minor meteor shower producing only about 10 meteors per hour. It is produced by dust grains left behind by comet 21P Giacobini- Zinner, which was first discovered in The Draconids is an unusual shower in that the best viewing is in the early evening instead of early morning like most other showers. The shower runs annually from October 6-10 and peaks this year on the the night of the 8th. The second quarter moon will block out all but the brightest meteors this year. If you are patient, you may be able to spot a few good ones. Best viewing will be in the early evening from a dark location far away from city lights. Meteors will radiate from the constellation Draco, but can appear anywhere in the sky. October 11 - Uranus at Opposition. The blue-green planet will be at its closest approach to Earth and its face will be fully illuminated by the Sun. It will be brighter than any other time of the

11 year and will be visible all night long. This is the best time to view Uranus. Due to its distance, it will only appear as a tiny blue-green dot in all but the most powerful telescopes. October 16 - Mercury at Greatest Western Elongation. The planet Mercury reaches greatest western elongation of 18.1 degrees from the Sun. This is the best time to view Mercury since it will be at its highest point above the horizon in the morning sky. Look for the planet low in the eastern sky just before sunrise. October 13 - New Moon. The Moon will located on the same side of the Earth as the Sun and will not be visible in the night sky. This phase occurs at 00:06 UTC. This is the best time of the month to observe faint objects such as galaxies and star clusters because there is no moonlight to interfere. October 21, 22 - Orionids Meteor Shower. The Orionids is an average shower producing up to 20 meteors per hour at its peak. It is produced by dust grains left behind by comet Halley, which has been known and observed since ancient times. The shower runs annually from October 2 to November 7. It peaks this year on the night of October 21 and the morning of October 22. The first quarter moon will set shortly after midnight leaving fairly dark skies for what should be a good show. Best viewing will be from a dark location after midnight. Meteors will radiate from the constellation Orion, but can appear anywhere in the sky. October 26 - Venus at Greatest Western Elongation. The planet Venus reaches greatest eastern elongation of 46.4 degrees from the Sun. This is the best time to view Venus since it will be at its highest point above the horizon in the morning sky. Look for the bright planet in the eastern sky before sunrise. October 26 - Conjunction of Venus and Jupiter. A conjunction of Venus and Jupiter will take place on October 26. The two bright planets will be visible within 1 degree of each other in the early morning sky. Look to the east just before sunrise for this impressive planetary pair. October 27 - Full Moon, Supermoon. The Moon will be located on the opposite side of the Earth as the Sun and its face will be will be fully illuminated. This phase occurs at 12:05 UTC. This full moon was known by early Native American tribes as the Full Hunters Moon because at this time of year the leaves are falling and the game is fat and ready to hunt. This moon has also been known as the Travel Moon and the Blood Moon. This is also the last of three supermoons for The Moon will be at its closest approach to the Earth and may look slightly larger and brighter than usual. October 28 - Conjunction of Venus, Mars, and Jupiter. A rare, 3-planet conjunction will be visible on the morning of October 28. The planets Venus, Mars, and Jupiter will all form a tight 1- degree triangle in the early morning sky. Look to the east just before sunrise for this spectacular event. Copyright 2015 Alachua Astronomy Club, Inc. All rights reserved. Contact FirstLight@alachuaastronomyclub.org Alachua Astronomy Club, Inc NW 13th St., #161 Gainesville, FL

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