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The Reflector Newsletter of the Peterborough Astronomical Association Solar Wind Creates — and Whips — a Magnetic Tail Around Earth

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The Reflector Newsletter of the Peterborough Astronomical Association Solar Wind Creates — and Whips — a Magnetic Tail Around Earth Volume 14 • Issue 7 September 2015 ISSN 1712-4425 peterboroughastronomy.com twitter.com/PtbAstronomical The Reflector Newsletter of the Peterborough Astronomical Association Solar Wind Creates — and Whips — a Magnetic Tail Around Earth Image credit: ESA / C. T. Russell (L), of Earth’s magnetic tail and its cause: the solar wind; Southwest Research Institute / IBEX Science Team (R), of the first image of the plasma sheet and plasmasphere created around Earth by the solar wind. ETHAN SEIGEL s Earth spins on its axis, stream of charged particles, the creating a long magnetotail that our planet’s interior spins solar wind, and has its own in- not only flattens and narrows, as well. Deep inside our tense magnetic field that extends but whips back-and-forth in the Aworld, Earth’s metal-rich core much farther into space than our onrushing solar wind. The par- produces a magnetic field that own planet’s does. The solar wind ticles are so diffuse that collisions spans the entire globe, with the travels fast, making the 150 million between them practically never magnetic poles offset only slightly km (93 million mile) journey to our occur, but the electromagnetic in- from our rotational axis. If you fly world in around three days, and is teractions create waves in Earth’s up to great distances, well above greatly affected by Earth. Under magnetosphere, which grow in Earth’s surface, you’ll find that this normal circumstances, our world’s magnitude and then transfer ener- magnetic web, called the magne- magnetic field acts like a shield for gy to other particles. The charged tosphere, is no longer spherical. It these particles, bending them out particles travel within the mag- not only bends away from the di- of the way of our planet and pro- netic field toward both poles, and rection of the sun at high altitudes, tecting plant and animal life from when they hit the ionosphere re- but it exhibits some very strange this harmful radiation. gion of Earth’s upper atmosphere, features, all thanks to the effects of But for every action, there’s they collide with ions of oxygen our parent star. an equal and opposite reaction: and nitrogen causing aurora. Mis- The sun isn’t just the primary as our magnetosphere bends the sions such as the European Space source of light and heat for our solar wind’s ions, these particles Agency and nasa Cluster mission world; it also emits an intense also distort our magnetosphere, See “Plasmasphere” on page 15 2 • peterboroughastronomy.com President’s Message Summer Draws To A Close he paa had a very active summer a viewing session at the Kinsmen Center. this year. We don’t have meetings in This was spearheaded by Boyd and he had July and August but many of us did additional help from paa members Brett Tgather for special events. We kicked these and Sean. August also saw our appearance off with the President’s bbq and viewing at Emily Provincial Park where we had session in June at the Robinson Road Ob- about seven telescopes set up and about ten servatory, a viewing session at the Crebar’s members. A good crowd of campers enjoyed in July and of course the annual Perseids the celestial delights. I received an invita- Meteor Shower in August. John Crossen tion to return next year to Emily the day and I visited Activity Haven to give a pre- after this event. sentation about the meteor shower the day As we enter the final four months of before. meetings for this year we need to start The meteor shower itself fizzled a bit but thinking about the annual election of of- our master of traffic control John Cameron ficers. A number of positions will be open reported that we had 404 members of the including that of president. This is my sec- public on the hill that night. John did his job ond term, fourth year and I will be stepping well. He prevented two city police cruis- down. ers from going up the hill. Well done John. Rodger Forsyth Peterborough Kids were also provided with PAA President Welcome Back e greet the fall return with a And don’t forget to check out the spectac- total lunar eclipse on September ular Perseid Meteor Shower portrait from 27th. This is the last of four con- John Chumak, our friend from Ohio. Wsecutive total lunar eclipses spanning over Till next month, enjoy this issue. two years, known as a Lunar Eclipse Tetrad. Phillip Chee This one is well placed for North American Editor, The Reflector viewing especially in the eastern part as it will be visible throughout. That isn’t the only highlight of the month. The other, of course, is the return of the club newsletter from it’s summer The Reflector hiatus. We have John Crossen reporting about the Perseid Meteor Shower viewing The Reflector is a publication of the Peterborough Astronomi- on Armour Hill and the Emily Park camp- cal Association (P.A.A.) Founded in 1970, the P.A.A. is your local group for astronomy in Peterborough and the Kawarthas. ers’ viewing. www.peterboroughastronomy.com • [email protected] Ken Sunderland has a surprising article Phone: 705.292.0729 Club Mailing Address on the phases of Venus. Rick Stankiewicz Rodger Forsyth, President reports on seeing “stars” during his trip to Peterborough Astronomical Association 536 Robinson Road RR #1 New York City. Peterborough, ON K9J 6X2 Vol 14 • Issue no. 7 • September 2015 • 3 The Reflector Close to Perfect Counts in Astronomy JOHN CROSSEN nd that’s just what it was on you look, the more you’ll see” was his sage August 12 atop Armour Hill. A few advice to novice observers. clouds drifted overhead, but noth- While wandering through the crowd Aing that blotted out the sky for hours. The I saw a number of people using the as- crowds were still coming up the hill as I was tronomy apps on their cell phones. “This is leaving at 10:45, so it looked as though at- cool” and “that’s amazing” were recurring tendance was excellent. comments from the digital dot watchers as paa members Brett Hardy, Rodger For- they compared their screens to the real stars syth, Michael McCarthy and Boyd Wood overhead. had their scopes set up with long lines of Jeanne Crebar was on hand along with eager stargazers waiting for a glimpse her grand-daughters who were visiting. Not through the eyepiece. Boyd had just re- bad for an 82-year-old lady. I often think of turned from a month-long motorcycle tour Jeanne as the female counter part of John of Newfoundland, so it was good to see him Dobson the famous telescope maker. Like back in the fold. him, Jeanne is filled with enthusiasm, cu- Prime targets for the night were Sat- riosity and an amazing amount of energy. urn, the Ring Nebula, the Double Cluster Jaime Morales was also on hand and I think and Andromeda. The rising fall constella- I heard Dean Shewring’s voice emanating tions also pleased the dot-connectors who from somewhere in the dark. I’m sure other recognized them from their star charts. I members were on hand to assist with the overheard people pointing out the Sum- stargazing and John Cameron was once mer Triangle and Deneb in Cygnus. Brett again directing parking and traffic flow up reminded viewers to take their time at the the hill. We all thank you, John. eyepiece and enjoy the sight. “The longer See “Armour Hill” on page 15 4 • peterboroughastronomy.com Emily Park 2015 A Great Turnout of Campers and PAA JOHHN CROSSEN mily Park has become a regular tering people growing from behind it. And outing for the Peterborough Astro- speaking of “every scope” the paa turnout nomical Association. Over the past was the best ever thanks to Brett, Rodger, Efew years we’ve seen the star party grow Harold, Boyd, Sean, Ken, Paul, David and from a Girl Scouts only affair to encompass yours truly with the annoying flash camera. all the campers. Sorry, you can’t take people pictures in the The Park Staff have also made some dark without a flash. improvements which we greatly appreci- Targets for the night included the First ate. Our most recent visit found the viewing Quarter Moon, Saturn, the Ring Nebula and grounds much more even and level. That a host more. Most of the scopes were GoTo made setting up and leveling scopes a lot models, so finding fresh celestial targets easier. Plus it made the ground safer for was a push-button cinch. And because all walking around in the dark. This year the GoTo scopes track with their object, there staff also blocked the road into the adjoin- was no time wasted realigning between ing parking area so there were no more viewers. headlights blasting across the viewing area. The event has become so popular that The public turnout for the event was we’ve been invited back again next August. fantastic. Every scope had a line of chat- Great work Emily Park Staff and the paa! When it Comes to Moons, Jupiter Outshines Them All Vol 14 • Issue no. 7 • September 2015 • 5 The Reflector Rodger and John Talk Up a Storm — A Meteor Storm Photo by Rodger Forsyth JOHN CROSSEN resident of the paa Rodger For- the air will cause them to burn up leaving a syth and Buckhorn Observatory’s plasma trail for our viewing pleasure. John Crossen presented the story As usual, Rodger and John’s presentation Pof the Perseid Meteor shower to a group of was followed by a lively question period.
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