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September 2019 the vol. 46 no. 09 Skyscraper September 2019 AMATEUR ASTRONOMICAL SOCIETY OF RHODE ISLAND 47 PEEPTOAD ROAD NORTH SCITUATE, RHODE ISLAND 02857 WWW.THESKYSCRAPERS.ORG In This Issue: Friday, September 6, 7:00pm 1 President’s Message at Seagrave Observatory 2 Solar Variability: Member Presentations: Our Inconstant Sun My Astronomical Summer 4 Solar Spectrum in the Sky Vacation This summer, Steve Hubbard was 4 Neptune at Opposition able to go to MARS (Maine Astron- 5 NASA Night Sky Notes: omy Retreat). He will be sharing 5 Spot the Stars some fun details and pictures of the of the Summer Triangle event which featured super dark 6 Globule Cluster in Sagitta: skies and some great viewing. Messier 71 Jim Hendrickson and Francine 7 The Sun, Moon & Planets Jackson recently returned from a in September trip to New York City where they visited many sites with cosmic sig- 9 AstroAssembly 2019 nificance. They will present some of their finds. Seagrave Observatory is closed as of August 28 until further notice. Out of an abundance of cau- tion, we will not be having any President’s night time observing due to the threat of EEE virus. We hope to Message reopen again in late September by Steve Hubbard or Early October. Please watch Now that summer is winding down, usually good weather, lots of visitors, great our website for updates. we are approaching one of my favorite As- speakers and of course, great food. tronomy seasons. Fall! Longer nights, cool This year is no exception. Your very hard temps and NO mosquitoes. It doesn’t get working second VP, Bob Horton and his Phases of the Moon much better than that, right? team have been hard at work putting anoth- And there are lots of great things to see er exceptional program together for us. We First Quarter Moon too. Like the Andromeda Galaxy, Saturn, have some wonderful speakers with very September 6 03:10 Cassiopeia and M15. We’ll be having an- interesting talks lined up for you. Take a Full Harvest Moon other member star party at the end of Sep- look at our website for more details. There’s September 14 04:33 tember, so there’s every reason to get those a link to register and everything you need telescopes, binoculars or just your eyeballs to know to make sure that you don’t miss Last Quarter Moon out there and enjoy all the late summer / this. September 22 02:41 early fall skies have to offer. When you look back on your life some- New Moon As if this wasn’t exciting enough, Fall is day, don’t subject yourself to regret, self-re- September 28 18:26 also AstroAssembly time!!! I can hardly be- crimination and heartache because you lieve it, but this will be my 46th year of As- missed AstroAssembly. You absolutely troAssembly. It’s always a great event with won’t regret it, I promise! Solar Variability: Our Inconstant Sun by Dave Huestis I went to bed last night wondering where visible, to solar maximum, where hundreds online looking to see if solar physicists were the Sun had gone. Then it dawned on me. A of sunspots can be counted. That peak ac- thinking of giving that period a name. Oth- little astronomy humor to begin a serious tivity then subsides back down to another er deep minimums which produced glob- discussion on our life-giving star—the Sun. solar minimum. This period is called a so- al climate effects received names like the Our Sun coalesced out of a vast cloud of lar cycle, and currently we are at solar min- Maunder Minimum (1645-1715), Dalton gas and dust some 100 times the size of our imum at the end of Cycle 24, which began Minimum (1790-1830) or Sporer Minimum solar system roughly five billion years ago. in January 2008. (All other solar activity (1450-1540). Fortunately, a group of the Gravity contracted this mass until the core follows this pattern, including solar flares, new cycle formed and Cycle 24 began. of this proto-star reached about 24.5 mil- prominences and coronal mass ejections Original forecasts of very high solar ac- lion degrees Fahrenheit. At that time nucle- (CME’s). tivity for Cycle 24 were predicted. However, ar fusion began, converting about 600 mil- There is also a 22-year cycle. At the end as the months progressed the forecasts were lion tons of hydrogen to helium per second. of an 11-year cycle, groups of the new cy- downgraded. This process has been ongoing since then. cle have reversed polarity magnetic fields. It is an easy task to follow the progress Most folks take for granted that the Sun You can read more about this topic and of each solar cycle. Decades ago, I used my rises and sets every day due to the Earth’s other pertinent solar facts on the Skyscrap- own telescope equipped with a special solar almost 24-hour rotation. The only change ers website: http://www.theskyscrapers. filter to conduct sunspot counts. This pro- most people recognize is the seasonal cy- org/stuff/contentmgr/files/2/f19a9ea97f- cess was fine for clear or partly cloudy days, cles caused by the fixed 23.5 degree tilt of 57f5a6effa42c91b8dc910/documents/so- but often around here in southern New En- our planet’s axis in its orbital path about the lar_lab.doc. The appearance of reversed po- gland we can experience days upon days of Sun. Reference this video to refresh your larity groups, along with the fact that they overcast skies. Today, solar observatories memory on the Earth’s annual journey: form at higher north and south solar lati- orbiting the Earth provide uninterrupted https://www.youtube.com/watch?v=d6rgy- tudes, indicates the Sun is transitioning to a high-resolution solar images, thereby mak- JkrMXg new cycle. However, groups of old and new ing sunspot counting very convenient. Although our Sun is a very stable G2 polarities do coincide during the transition. Several members of Skyscrapers have yellow dwarf star, it does have a slight “vari- Current Cycle 24 was slightly unusual been participating in a sunspot count proj- ability.” Over an average 11-year cycle solar in that it sported two peaks. The largest, in ect since September 18, 2012. In addition, in activity waxes and wanes. Most apparent of April 2014, was preceded by an earlier peak order to provide my Bryant University as- this activity manifests itself in the appear- in March 2012. Despite this scenario, Cycle tronomy lab students an “eyes on” project, ance of dark sunspots, regions of intense 24 displayed the lowest peak since 1906. they conduct sunspot counts for an 11-week magnetism residing as depressions in the Also, the last minimum, between Cy- period each semester. During solar max- Sun’s photosphere (the visible “surface” cle 23 and Cycle 24, was quite deep (pro- imum it was indeed a challenge for them of the Sun). Solar activity rises from solar longed). There were many spotless days. At to get the hang of determining groups and minimum, where no or few sunspots are the time I was searching the solar literature counting spots. However, by the end of a The Skyscraper is published President Outreach Chairperson monthly by Skyscrapers, Inc. Steve Hubbard [email protected] Linda Bergemann [email protected] Meetings are held monthly, usually on the first or second 1st Vice President Observatory Committee Chairperson Friday or Saturday of the month. Jim Hendrickson [email protected] Jeff Padell [email protected] Seagrave Memorial Observatory is open every Saturday night, 2nd Vice President New Member Steward weather permitting. Bob Horton [email protected] Tracy Prell [email protected] Directions Secretary Librarian Directions to Seagrave Memorial Observatory are Kathy Siok [email protected] Dave Huestis [email protected] located on the back page of this newsletter. Treasurer Assistant Librarian Submissions Submissions to The Skyscraper are always welcome. Matt Ouellette [email protected] Weston Ambrose Please submit items for the newsletter no later than September 15 to Jim Hendrickson, 1 Sunflower Cir- Members at Large Historian cle, North Providence, RI 02911 or e-mail to jim@ Bob Janus [email protected] Dave Huestis [email protected] distantgalaxy.com. Lloyd Merrill [email protected] Editor E-mail subscriptions Trustees Jim Hendrickson [email protected] To receive The Skyscraper by e-mail, send e-mail Jeff Padell [email protected] with your name and address to jim@distantgalaxy. Astronomical League Correspondent (ALCor) com. Note that you will no longer receive the news- Jim Crawford [email protected] Jeff Padell [email protected] letter by postal mail. Conrad Cardano [email protected] 2 The Skyscraper September 2019 semester most of them became good solar sphere to shrink, preventing space debris read reports hoping for a Maunder-type observers. I wish they could have continued from de-orbiting due to atmospheric drag. minimum in the hopes a decades-long once the lab finished. The opposite extreme also poses dan- solar minimum would mitigate the effects As Cycle 24 continues towards solar ger. When solar activity is high, our atmo- of global warming. Yes, global warming. minimum (a determination of which can sphere expands, thereby increasing drag on Precisely stated. Climate change says little. be made only after we have reached and our orbiting spacecraft. In fact, Skylab, a I’ve become quite cynical as I’ve aged, and surpassed it), there have been many spot- United States orbital laboratory, reentered I believe humankind is past the point of less days. 2018 totaled 221 days, while 2019 the Earth’s atmosphere ahead of schedule in intervention.
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