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STAR FIELDS
Newsletter of the Amateur Telescope Makers of Boston Including the Bond Astronomical Club Established in 1934 In the Interest of Telescope Making & Using Vol. 27, No. 7 July 2015

Sperling received a BA from Michigan State University after graduating from Montgomery Blair High School in Silver Spring, Maryland. He followed that with an MA in History of Science from the University of California, Berkeley. He has taught astronomy and related courses at Sonoma State University, California State University, Hayward, UC Berkeley, and San Francisco State University. He has also taught many personal interest adult classes. Sperling currently lives in San Mateo, California. Norm founded the astronomical supplier and publisher blog, Everything in the Universe, in 1977. He was an assistant editor for Sky & Telescope magazine and, as of 2011, the editor and publisher of the Journal of Irreproducible Results, a science humor magazine. He has authored What Your Astronomy Textbook Won't Tell You and edited and published John Dobson's book How and Why to Make a User-Friendly Sidewalk Telescope. He has also been published in Technology Review, Astronomy, Pacific Discovery, Journal of College Science Teaching, Mercury, Popular Astronomy, Telescope Making, Griffith Observer, and Reflector. Norm also invented for Spherical Concepts, Inc. an acrylic globe named "The Stars Above", which is sold as a personal planetarium. Please join us for a pre-meeting dinner discussion at Changsho, 1712 Mass Ave, Cambridge, MA at 6:00pm before the meeting.

This Month's Meeting . . .
Thursday, July 9th, 2015 at 8:00 PM Phillips Auditorium Harvard-Smithsonian Center for Astrophysics Parking at the CfA is allowed for the duration of the meeting

Aurora Borealis. . .

Development of the Astroscan Wide-Field Newtonian
This month's speaker will be former ATMoB member, Norman Sperling. Norm will cover some of the history and background of the development of the popular Astroscan telescope. The Astroscan is a wide-field Newtonian reflector telescope produced by the Edmund Scientific Corporation. It was designed by Norman Sperling and Mike Simmons to be used as an introductory telescope. Rather than using a more traditional equatorial or alt-azimuth mount, the Astroscan features a spherical housing around the primary reflector, which sits in a cast aluminum cradle. The design is durable and allows for simple operation by novice amateur astronomers. It won an Industrial Design Award in 1976.
Aurora Borealis. June 23, 2015, Harvard, MA. Image by Al Takeda

Sunspot, Active Region AR2371, produced an M2 class flare and sent a coronal mass ejection toward the Earth on June 21st. On the evening of June 22rd, the Kp index fluctuated between 7-8 and produced an auroral display that was seen visually. Faint whitish "curtains" could be detected and occasionally, dim reddish areas would appear on the northern horizon between the Big Dipper and Cassiopeia. ~ Al Takeda ­ Member at Large and Newsletter Editor ~


June Meeting Minutes . . .
Minutes of ATMoB Annual meeting held on June 11, 2015 in the Phillips Auditorium at the Harvard-Smithsonian Center for Astrophysics. President Neil Fleming called the meeting to order at 8:00 PM. The Secretary's Report of the May 14, 2015 meeting was prepared and given by Glenn Chaple. Eileen Myers gave the Treasurer's report. Tom McDonagh gave the Membership Secretary's report Glenn Chaple gave the Observing Committee Report: Steve Clougherty gave the Clubhouse Report Old Business: The election of officers was conducted by President Neil Fleming. The nominees presented by the Nominating Committee were: President: Neil Fleming Vice President: Glenn Chaple Secretary: Sidney Johnston Membership Secretary: Tom McDonagh Treasurer: Eileen Myers Member at Large: Bruce Tinkler Member at Large: Al Takeda The Secretary was asked if other nominations were made. Sidney reported that no other nominations were presented to him. Since no other nominations were put forward to challenge the nominees presented by the nominating committee, a voice vote was taken. Election results: Accept the nominations for the positions: Unanimous, by voice vote. No votes: none Abstentions: none A proposal to increase the dues for the ATMoB was presented to the membership. The Proposal: Keep the reserve fund constant Increase the dues to fund operating expenses with dues collected. The proposal presented the current yearly dues and type of membership, and the proposed increased yearly dues: as followed:

Type of Membership General Family Senior: Student

Current Dues $25.00 $35.00 $12.50 $12.50

Proposed increase $35.00 $45.00 $15.00 $15.00

An extended discussion followed presentation of the proposed dues increase. A motion to accept the proposed dues increase was made: Moved: Mario Motta Seconded: Chase Green A vote by show of hands was taken: Accept the proposal: Unanimous No: none Abstentions: none New Business: None The June meeting program consisted of presentations made by our members.

Mario Motta *

Dr. Mario Motta, MD spoke about the harmful effects light emitted by certain Light Emitting Diodes (LEDs) with a color temperature greater than 3,000 Kelvin outdoor lighting. Mario explained that LEDs with temperature of 2,700 Kelvin are available, and insisted th should be used instead.

of blue - those used in a color at those

Although manufacturers advertise the older LEDs as white lighting, the chemical nature of these LEDs produces blue light. The blue light increases glare and has a detrimental effect on people's biological circadian rhythm. There are blue sensitive detectors in the eyes, which have nothing to do with seeing, but are sensitive to the blue light of our sky. These detectors have an effect on the hormone melatonin, which is produced in the brain. This hormone is important in regulating the day and night biological cycles. Plants and animals are also negatively affected by the emission of excess blue light by LEDs and other artificial lighting.

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Mario cautioned us that commercial LEDs with higher color temperatures are being "pushed" by certain companies and should not be used for outdoor lighting purposes. Some towns have been sold on installing the higher color temperature LEDs as streetlights. It is recommended by the International Darksky Association (IDA) that members urge towns to not install the higher effective temperature LEDs. On a more positive note, there are newer LED designs that use an absorbing layer incorporated into their structure to absorb the excess blue light. LEDs which do not emit the undesired blue light are available. Research is ongoing to make better ones. Some cities that initially had 4,000 Kelvin LED lighting have switched to 2,700 Kelvin lighting after much public outcry over the glare produced by the blue LEDs . A lengthy report by Dr. Mario Motta, MD on the harmful effects of LEDs with high emission of blue light is available at: http://artificiallightatnight.weebly.com/uploads/3/7/0/5/370534 63/motta-mario.pdf .

the spacecraft after it passes Pluto. Editors Note: KBO 2014 MU69 has been selected by NASA to be the next target for the New Horizons spacecraft. Penny Lucinian gave a report on her radio observations of radio waves arriving at Earth from outer space. She described her antenna and electronics for making radio astronomy observations in the 20 megahertz frequency band, including 19.020 to 19.990 megahertz. The meeting was adjourned at 9:30 PM. ~ Sidney Johnston, Secretary ~

Membership Report . . .
Membership count as of June 26, 2015, is at 320 individuals. Please welcome our newest and returning members: Nikosi Muhangi, Mark Bouyer, Walter Carrington, John Bilancieri, and Anees Buxamusa. The club's fiscal year began June 1st. The membership renewal period begins at this time. Please renew today! Many members' subscriptions to S&T and Astronomy magazine are tied to their last renewal date. You can avoid interruption of subscription delivery by renewing now! Please follow the instructions outlined in the June 2015 Starfields newsletter. New members in 2015 are not required to renew at this time. If you cannot access the website or have forgotten your password, please contact me via email at: membership@atmob.org. Our communication lifeline includes the ATMOB-Announce and ATMOB-Discuss mailing lists as well as our fantastic newsletter. Please refer to these tools for up to date information on Clubhouse openings, events and interesting astronomy related discussions. Contact me with questions regarding accessing these options at: membership@atmob.org. The Amateur Telescope Makers of Boston, Inc. is a 501(c)3 organization. Donations are gladly accepted and are tax deductible to the fullest extent allowed by law. Consider making a tax-deductible contribution to the club during your estate and tax planning this year. Many companies make matching contributions at an employee's request. It is a simple way to make your donation go twice as far.

Bernie Voltz updating the membership on the upcoming 2017 eclipse trip. *

Bernie Volz gave a report on the planned eclipse trip scheduled for August 2017. Plans are to stay at the Stony Creek Inn in Columbia, Missouri. The group's first choice for viewing is at Les Bourgeois Vineyards located in Rocheport, Missouri. Plans are to drive to secondary location if clouds appear.

John Sheff talked about the New Horizons planet Pluto mission. *

~ Tom McDonagh ­ Membership Secretary ~

John Shelf gave a report on the flyby of the planet Pluto by the New Horizon Spacecraft. A Kuiper Belt object will be visited by 3


Annual Club Picnic at the Clubhouse . . .
Saturday, September 19, 2015 at 3:00 PM All Members and their Families are invited Saturday, September 19th is the date of this year's Annual Club Picnic at the Clubhouse in Westford, start time 3:00 P.M. Enjoy a day with good food and lots of astronomy talk with other ATMoB members. Please bring a favorite dish to share soup, appetizer, fancy bread,... A helpful. We will provide hamburg ketchup, mustard, coffee, paper goods - salad, main dish, dessert, serving utensil would be ers, drinks, potato chips, and plastic cutlery.

May 2015 Clubhouse Report The clubhouse hosted two work parties during May and a total of 26 members and friends were on hand for various projects. Tree and brush trimming continued in May and several members helped haul away numerous loads to the tree line on the West side of the property. We have completed about half of the necessary trimming on the East side of the observing field to date. Other members scraped and sanded the porch railing on the clubhouse. The railing and posts will be stained once this prep work has been completed. Special thanks to John Blomquist for hauling his tractor to the clubhouse during the week and spending nearly 5 hours mowing the lawn. His effort has greatly reduced the number of members needed to hand push-mow the property. Phil Rounseville conducted a mirror cleaning clinic during the afternoon of the second work party on May 30. John Maher trained a group of members who are interested in using the Meade 10 inch SCT telescope housed in the clamshell observatory. Thanks to the kitchen crew for providing a great lunch on both occasions. The next scheduled work party will be held on Saturday, Aug. 1. Thanks to the following members and friends for all of their volunteer efforts during the month of May: Susan Adam, Jason Adam, Joshua Ashenberg, John Blomquist, Paul Cicchetti, Steve Clougherty, Paul Courtemanche, Nina Craven, Karl Dean, Jeffrey Dean, Charlie Gettys, Jim Gettys, Joe Henry, Jan Hoey, Eric Johanson, Dick Koolish, Penny Lucinian, John Maher, Mike Mattei, Bill Murphy, Eileen Myers, Gary Phillips, Dave Prowten, Cheryl Rayner, John Reed, Bill Robinson, Phil Rounseville, Jacob Siegel, Art Swedlow, Al Takeda, Bill Toomey, Sai Vallabha, and Joe Wolfe. ~ Clubhouse Committee Chairs ~ ~ Steve Clougherty, John Reed and Dave Prowten ~ Clubhouse Saturday Schedule July 11 THE CONJUNCTION Joe Henry + Cheryl Rayner July 18 Karl Dean Bill Robinson July 25 John Maher Glenn Meurer Aug 1 WORK PARTY # 8 Eileen Myers + Rich Nugent Aug 8 Brian Maerz John Panaswich Aug 15 STELLAFANE Aug 22 Dave Siegrist Bill Toomey Aug 29 WORK PARTY #9 Bruce Berger + Mike Hill Sept 5 ARUNAH HILL DAYS Jim Gettys + Eileen Myers Sept 12 Eileen Myers Rich Nugent

Club members, their families and friends are invited. There will be astronomy activities for kids of all ages. Planned activities are a tour of the clubhouse facilities, a demonstration of mirror grinding, and the ever popular walk "up the hill", stopping along the way to talk about the MIT Haystack Observatory facility. Share your astronomy stories and experiences. Bring any astrophotography images you would like to show. There will be daytime H-alpha and white light solar viewing and night sky observing after sunset (all, weather permitting). The picnic is on rain or shine. Bring lawn chairs or blankets to sit on. Bring your favorite suntan lotion and mosquito repellent. Observing will continue until Midnight if the sky is clear, so bring your telescope and your observing clothing and gear. The club's scopes will be open too. Directions to the Clubhouse can be found on the last page of Star Fields and at the club website www.atmob.org. Questions - Email Eileen Myers at starleen@charter.net Don't miss the fun! Organized by ATMoB's Good Times Co-Hosts and Co-Chefs ~ Eileen Myers ­ Treasurer ~

Clubhouse Report . . .

Steve Clougherty Weed Whacking *

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Sky Object of the Month . . .
July 2015 Xi () Scorpii (1998) ­ Double Star in Scorpius

When I first viewed xi Scorpii with a 3-inch reflecting telescope in the summer of 1971, I was surprised to see a faint double star in the same field. I had "discovered" 1999 (magnitudes 7.5 and 8.1; separation 11.8". Although nearly 5 minutes of arc separate 1999 from xi Scorpii, the two have the same common proper motion and are likely gravitationally bound. When viewing xi Scorpii and 1999, pay close attention to the colors of their component stars. Xi Scorpii A and B are Ftype stars, while C is a cooler G8 dwarf. Both 1999 stars have K spectral classes. What colors do you see?

Sketch by Jeremy Perez (www.perezmedia.net)

Our cosmic wanderings take us 93 light years away to the triple star xi () Scorpii (1998), located in the Scorpion's northwest corner. A 60mm refractor magnifying 60X will reveal two stars (xi Scorpii A and C), of magnitudes 4.9 and 7.3 and separated by 7.0". If the seeing is extremely steady, check out the brighter star with a larger scope (minimum aperture of 4 inches) and magnification of 150X or more. You should capture a magnitude 5.2 companion (xi Scorpii B) just 1.1" away. Xi Scorpii A and B are a binary pair with an orbital period of 46 years. As the diagram shows, they are currently near greatest separation.

www.dibonsmith.com

~ Glenn Chaple ­ Observing Committee and VP ~

Sky Object of the Month . . .
August 2015 SS Cygni ­ Dwarf Nova in Cygnus

Light curve for SS Cygni over 500 day period (AAVSO)

www.constellation-guide.com

Having been a member of the American Association of Variable Star Observers (AAVSO) for the past 35 years, I was recently asked to name my favorite variable star. I answered without hesitation, "SS Cygni." I'm not alone. It's a favorite among many variable stars, and here's why.

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SS Cygni is a prime example of a dwarf nova. Most of the time, it shines at a magnitude of around 12. Suddenly and without warning, it brightens to 8th magnitude ­ the four-magnitude jump taking a day or less. Such an outburst lasts for several days to a week before SS Cygni returns to quiescence. The outbursts occur at approximately 50-day intervals (see accompanying light curve). If you were to start observing SS Cygni now and each clear night to follow (you never know when the next outburst might occur), you might catch 2 or 3 before Cygnus drops low in the northwest sky in December. The accompanying finder charts show the way to SS Cygni. Begin by centering your finder on the 5th magnitude star 75 Cygni, found by tracing a line from delta Cygni through Deneb and extending it an equal distance beyond and slight northward (Chart A). Using a low-power eyepiece, you should encounter a V-shaped group of stars headlined by 75 Cygni (labeled by its magnitude [5.1 with decimal omitted] in Chart B). The opening of the V leads to a triangle of 8th and 9th magnitude stars. Chart C is a close-up of the triangle, showing the magnitudes of nearby stars (again, decimals omitted) and the location of SS Cygni itself. A star hop to SS Cygni might take 10-15 minutes on your first attempt ­ perhaps 5-10 on the next. After a few evenings, you should be able to lock onto SS Cygni in a minute or less. Then the fun begins. SS Cygni might even be at outburst that first night. If not, keep a nightly vigil. That first night an 8th magnitude star greets your eye where a 12th magnitude one had been the night before should have you hooked! About 372 light-years away, SS Cygni was discovered in 1896 by Louisa D. Wells of the Harvard College Observatory, and has been observed nonstop ever since. Like its kindred dwarf novae, of which over 375 are known, SS Cygni is a tight binary comprising a red dwarf and white dwarf orbiting each other ­ in this case every 6 Ѕ hours. Material from the red dwarf is gravitationally pulled towards the white dwarf, spiraling inward to form an accretion disk. Instabilities in the accretion disk lead to the outbursts. For reasons I've already mentioned, SS Cygni is one of the most-observed variable stars in the night sky. It's bright enough, even at quiescence, to be glimpsed in a 4-inch scope. I encourage you to join the crowd and discover for yourself the allure of this fascinating variable star.

Chart B (AAVSO)

Chart C (AAVSO)

Upcoming Conventions . . .
Connecticut River Valley Astronomers Conjunction
Friday, July 10, 2015 through Sunday, July 12, 2015 Some ATMoB members stay over Friday night to observe; some go only for the day on Saturday Northfield Mountain Recreation and Environmental Center 99 Millers Falls Road (Route 63), Northfield, MA 01360 Highlights: Solar observing ("Barlow Bob" Memorial Solar Star Party), dark sky observing, lectures, swap tables, raffle prizes Speakers: Jack Megas - "The Universe According to Chaple"

Chart A (freestarcharts.com)

Steve Hubbard - "Dance of the Polar Lights"

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Dick Parker - "Building Your Own Antique Telescope" Ed Faits - "Humans or Robots: The Future of Space Exploration" Keynote Speaker: J. Kelly Beatty ­ "Encounter with Pluto" http://www.philharrington.net/astroconjunction/

Discoveries" Kim Arcand - "Light and IYL 2015" Andrew Vanderburg - "Kepler's Second Chance: Planet Discoveries from the K2 Mission" Keynote Speaker: J. Kelly Beatty ­ "Light Pollution and the International Dark-Sky Association"

Stellafane Convention
Presented by the Springfield Telescope Makers Thursday, August 13, 2015 through Sunday, August 16, 2015 Springfield, Vermont Highlights: Dark sky observing, solar observing, lectures, mirror grinding and telescope making demos, swap tables and raffle prizes. ATMoB Speakers: Al Takeda ­ "Deep Sky Imaging with Small Scopes" Glenn Chaple "Seeing Red ­ Observing Carbon Stars" "An Introduction to Telescopes for All Ages" Mario Motta ­ "The Health and Environmental Dangers of Blue Light at Night" Phil Rounseville ­ "Making Pitch Laps" John Briggs ­ "Discover and Enjoy the Night Sky" John Briggs is also the founder and organizer of the Hartness House Workshop Series. This year's theme: Innovation in Astronomy Education and Outreach http://stellafane.org/convention/2015/2015-hhw.html Thursday, August 13, 2015 Hartness House, Springfield, VT www.stellafane.org

For Sale . . .
George East has retired and is selling his house and observatory in Sudbury. The following items are for sale: Vintage fork-mounted Celestron 14 with Byers retrofit drive, wedge and tripod. Primary mirror needs re-coating. $2000 SBIG ST-8XE CCD Camera and CFW-8 5-position Filter Wheel with L, R, G, B, H-Alpha filters. $1000 Mirror grinding machine. $100 Bridgeport vertical milling machine with J Head and 9" x 36" table, 1 Hp motor and phase converter, collets, vise, rotary table, drill chuck, boring head, and misc. milling cutters. $2500 South Bend lathe, 16" swing x 36" between centers, phase converter, collets, taper attachment, 3 and 4 jaw chucks, face plate, boring bar, follower, steady rest, drill chuck and misc. tool holders and cutting bits. $1800 Note: Phase converter allows 3-phase motor to operate from household power. Please contact George at George.East@comcast.net or 978-460-3049. ~ Submitted by George East ~

AstroAssembly 2015
Friday, October 2, 2015 through Saturday, October 3, 2015 47 Peeptoad Road North Scituate, Rhode Island www.theskyscrapers.org/astroassembly2015 Highlights: Solar observing, lectures, swap tables, raffle prizes Speakers: J. Kelly Beatty - "New Horizons Flyby of Pluto ­ The Latest 7

Editor: * Photos by Al Takeda unless otherwise noted.

************************************** September Star Fields DEADLINE Sunday, August 23rd Email articles to Al Takeda at newsletter@atmob.org Articles from members are always welcome. **************************************


POSTMASTER NOTE: First Class Postage Mailed September 14, 2015 Amateur Telescope Makers of Boston, Inc. c/o Tom McDonagh, Membership Secretary 48 Mohawk Drive Acton, MA 01720 FIRST CLASS

EXECUTIVE BOARD 2015-2016
PRESIDENT: VICE PRES: SECRETARY: MEMBERSHIP: TREASURER: Neil Fleming Glenn Chaple Sidney Johnston Tom McDonagh Eileen Myers president@atmob.org (978) (978) (617) (978) 597-8465 505-9169 966-5221 456-3937

How to Find Us... Web Page www.atmob.org
MEETINGS: Held the second Thursday of each month (September to July) at 8:00PM in the Phillips Auditorium, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge MA. For INCLEMENT WEATHER CANCELLATION see www.atmob.org and check your email on the ATMOB-ANNOUNCE list. CLUBHOUSE: Latitude 42 36.5' N Longitude 71 29.8' W The Tom Britton Clubhouse is open every Saturday from 7 p.m. to late evening. It is the white farmhouse on the grounds of MIT's Haystack Observatory in Westford, MA. Take Rt. 3 North from Rt. 128 or Rt. 495 to Exit 33 and proceed West on Rt. 40 for five miles. Turn right at the MIT Lincoln Lab, Haystack Observatory at the Groton town line. Proceed to the farmhouse on left side of the road. Clubhouse attendance varies with the weather. It is wise to call in advance: (978) 692-8708. -------------------------------------------------------------------------------------

MEMBERS AT LARGE: Bruce Tinkler Al Takeda PAST PRESIDENTS: 2012 ­ 14 2010 - 12 2006 - 08 COMMITTEES CLUBHOUSE : Mike Hill Bernie Kosicki Virginia Renehan John Reed Steve Clougherty David Prowten Bruce Berger Al Takeda

(781) 862-8040 (508) 494-7877 (508) 485-0230 (978) 263-2812 (978) 283-0862 (781) 861-8031 (781) 784-3024 (978) 369-1596 (978) 387-4189 newsletter@atmob.org

OBSERVING: NEWSLETTER

Heads Up For The Month . . .
To calculate Eastern Daylight Time (EDT) from Universal Time (UT) subtract 4 from UT. July 15 New Moon July 18 Venus 0.4-deg N. of Moon July 24 First Quarter Moon (Moonset at midnight) July 28-29 S. Delta Aquariid Meteors peak July 31 Full Moon Aug 6 Last Quarter Moon (Moonrise at midnight) Aug 13 Perseid Meteors peak Aug 14 New Moon Aug 22 First Quarter Moon (Moonset at midnight)

----------PUBLIC OUTREACH STAR PARTY COORDINATOR: Virginia Renehan

starparty@atmob.org