Gazer News

Astronomy News for Bluewater Stargazers Vol 14 No.2 Mar/Apr 2020 Mar/Apr 2020 SGN Contents p 1: From the President; and a home for the dome! p 2: Southern Cross spotted -twice. p 3: Special Feature: What’s going on with ? p 4: Betelgeuse: Comparison images p 5: Betelgeuse: pronunciation and dimming explained? p 6: New aurora type discovered -amateurs helped again! p 7: More about “dune” aurora p 8-10: Quetican Field of View: Iceland: Fire and Ice This month’s feature (see pg 13) is , the p 11: Sky Sights: March/April Hunter. Three articles on Betelgeuse can be found on pg 3 to p 12: Sky Sights: (cont’d) 5. In Orion this winter, note the star α-Orionis (Betelgeuse). Its p 13: Constellation page: Orion p 14: Miscellaneous Page and Classifieds magnitude has noticeably dimmed and it now shines fainter p 15: Image of the Month: from Machu Picchu than (magn. 1.64) in Orion’s other shoulder. See pg 4 for more about observing the brightness changes yourself. From the President: The weather gods treated me very perversely over the The charming cartoon above was drawn by astronomy last two weeks of January. Rebecca and I decided to professor George Reed (West Chester University), who take a holiday away from the snow and ice by travelling promoted astronomy in his courses/planetarium programs. I to Peru and Ecuador to visit Machu Picchu and the came across these first when his complete sky charts were Galapagos Islands. This is the low season down there published in May 1980 in Sky&Telescope. They remain my but it also happens to be the rainy time of (I found favourites. George Reed passed away August 2016. that out after we had booked!). So we packed our rain Coleman Dome Stays in Bruce! gear and anticipating cloudy weather I did not take any of my DSLRs to do any astro imaging.

So, guess what? Over the two weeks we were there we got a total of about 2 hours of rain. Most days were either bright and sunny (Peru) or just cloudy and pleasantly warm. The Galapagos were downright hot and very humid. Zeus, (the god of the sky, rain, thunder and lightning) must have been otherwise occupied.

In Cusco, Peru, there were nights when the skies were clear and I saw Venus near the crescent Moon on several occasions. Also during an early morning transfer to the airport for a morning flight to Quito, up in the sky was the Southern Cross with α and β-Centauri nearby. (See pg 2). Cusco was the farthest south we got, 13° BAS member Frank W. has rescued the Coleman Dome. below the equator so Orion which is on the celestial Frank plans to refurbish it atop a suitable building to add equator would be past the zenith to the north by that another observatory to his Allenford “complex”. Frank has amount. It was strange to see it lying on its side. Also contacted ObservaDome which built it in the 1970’s for strange was the fact that the first crescent Moon was parts to bring it back up to operating condition. Let Frank sunlit on the east side like a last crescent in northern know if you would like to help out in the rebuild project. It skies. And Venus sank virtually straight down into the would be good experience to see how one of these comes horizon in the west. Lesson learned: Always, always, together. He already has one volunteer -the guy who helped always pack your best camera on trips! take it apart -that was a sad day…) S G N Crux Spotted Mar/Apr 2020 pg 2

Disclaimer: S G N reports on the activities of the Bluewater BAS Executive 2020-2021 Astronomical Society (formerly Bruce County Astronomical President: John Hlynialuk [email protected] Society) but any opinions presented herein are not necessarily V-President: Eric Ingard [email protected] endorsed by BAS. See the BAS website at Secretary: Lorraine Rodgers [email protected] www.bluewaterastronomy.com for up-to-date details relating Treasurer: Cheryl Dawson [email protected] to BAS events. SGN is produced and edited by John Hlynialuk Memb-at-Lrg: Zoë Kessler [email protected] and I am solely responsible for its content. Your original articles, Membership: Marian Ratcliffe [email protected] images, opinions, comments, observing reports, etc., are welcome. I reserve Past Pres: Brett Tatton [email protected] the right to edit for brevity or clarity. Errors or omissions are entirely mine. I will not publish your emails or other materials without your specific permission. No part of this publication shall be reproduced in any form whatsoever without the editor’s consent. However, the Sky Calendar and Feature Constellation pages are free to copy for non-commercial use. Feel free to forward this issue in its entirety to friends. Email comments and/or submissions to [email protected]

Southern Cross spotted The first time I saw Crux was in 2011 on a trip to do astronomy in Chile. (Image at bottom). A lot of planning went into that sighting, but the second time I spotted Crux was totally by accident. On Jan 27, Rebecca and I were waiting for an early morning transfer to the Cusco airport after our visit to Machu Picchu and the hotel where we waited for the cab happened to have an open air courtyard. Up in the sky was the Southern Cross with alpha and beta-Centauri neatly framed by the two-story structure. At 4:58 am Crux was about 42° in elevation. (Image right). The only camera I brought was a Canon point-and-shoot but it did have a long exposure setting. I captured both Crux and to its left the two brightest in Centaurus. Dawn was breaking so it is not the best shot I have ever taken. The image lower right taken with a proper DSLR on a tracking mount shows what the area looks like from a dark sky site (Chile, 2011).

Image right: Southern Cross on Apr. 1, 2011 from San Pedro de Atacama. The fifth star of the asterism, the “base runner” is visible between “2nd and 3rd base”. Lower right of frame is the eta- Carina Nebula; the “star” in upper left is actually the globular cluster omega- Centauri, which was labelled a star by early mappers. The dark patch below Crux is the . The Incas say that the god Ataguchu, in a fit of temper, kicked the Milky Way and a fragment flew off, forming the Small Magellanic Cloud leaving the black mark of the Coalsack behind. Beware of Inca gods in a bad mood! In this shot alpha and beta Centauri are left of photo. Canon 50D, 118 s exposure at ISO 2000, f/4.5 at 38 mm focal length (17-85 mm zoom). Image piggy back Polaris mount. S G N What’s Happening to Betelgeuse? Mar/Apr 2020 pg 3 Betelgeuse Fades from 0.5 to 1.66 Magnitude! Universe Today reports that Betelgeuse keeps getting dimmer and dimmer and everyone is wondering what exactly that means. The star will go supernova at the end of its life, but that's not projected to happen for tens of thousands of or so. So what's causing the dimming? Villanova University astronomers Edward Guinan and Richard Wasatonic were the first to report Betelgeuse's recent dimming and in a new post on The Astronomer's Telegram, they report a further dimming of Betelgeuse. They also point out that although the star is still dimming, its rate is slowing.

Betelgeuse is a red supergiant star in the constellation Orion. It left the main sequence about one million years ago and has been a red supergiant for about 40,000 years. It's a core- collapse SN II progenitor, which means that eventually, Betelgeuse will burn enough of its hydrogen that its core will collapse, and it will explode as a supernova. It's a semi- regular variable star, with cycle of about 420 days long, and another of about five or six years. A third cycle is shorter; about 100 to 180 days. Though most of its fluctuations are predictable and follow these cycles, some of them are not, like the current dimming. This artist’s visualization shows Astronomers have been monitoring Betelgeuse for a long time. Visual estimates of the star go back about 180 years, Betelgeuse as it was revealed by new and since the 1920s, the American Association of Variable observation techniques with ESO's Star Observers (AAVSO) have taken more systematic Very Large Telescope. These measurements. About 40 years of photometric measurements observations led to the sharpest-ever by Villanova University astronomers show the star is as dim looks at the star. (Image credit: ESO/L. as it's ever been. Calçada)

According to Guinan and Wasatonic's post on Astronomer's Telegram, Betelgeuse's temperature has dropped by 100 Kelvin since September 2019, and its has dropped by nearly 25 percent in the same time frame. According to all happen, they just don't know when. Whatever the cause, we of those measurements, the star's radius has grown by about know the eventual end: a supernova explosion. 9 percent. This swelling is expected as Betelgeuse ages. Whether this dimming is directly related to the approaching Betelgeuse is close in astronomical terms, only about 650 cataclysmic death of this unstable star is unknown. As Guinan light-years away, and that makes it the only star other than our and Wasatonic say on Astronomer's Telegram, "Betelgeuse Sun on which we can see surface details. Like all stars, should be closely watched.” Betelgeuse generates heat in its core through fusion. The heat is transferred to its surface via convection. The currents that When Betelgeuse does eventually go supernova, it will be the carry the heat are called convection cells, which can be seen most fascinating act of nature ever witnessed. Other on the surface as dark patches. As the star rotates, these cells supernovae like SN 185 and SN 1604 were much farther rotate in and out of view, which contributes to Betelgeuse's away than Betelgeuse, which will become the third brightest observed variability. Convection cells can be massive, even object in the sky, perhaps even brighter. Betelgeuse will light more so on the surface of a huge star like Betelgeuse. up the sky like no other supernovae, and will last for months, visible in daytime, casting shadows at night. This dimming episode may not be the star itself, but rather a Then in about three years, it will fade to its current brightness. cloud of gas and dust obscuring the light. As time goes on, About six years after it goes supernova, Betelgeuse won't and Betelgeuse burns more of its fuel, it loses mass. As it even be visible in the night sky. Orion the Hunter will be loses mass, its gravitational hold on its outer edges is missing a star. weakened, and clouds of gas escape the star into the surrounding regions and dim the light being emitted. When exactly all this will happen, nobody knows. And though this recent dimming likely isn't directly connected to We've never been able to observe any other red super-giants Betelgeuse's eventual supernova explosion, astronomers the way we can Betelgeuse. Astronomers know what will don't know that for sure either. S G N Betelgeuse drops from 12th to 29th place! Mar/Apr 2020 pg 4

Betelgeuse has dimmed in brightness significantly in the last and centre star, are 1.74 and 1.69 respectively. In the lower few months and if you look closely, you can tell the difference left corner of Orion, opposite (-0.03), the faintest star of in the appearance of the constellation. Starting around the the Orion rectangle is at magnitude 2.07. Another star end of September, the brightness of Betelgeuse slowly in the neighbourhood is also comparable in brightness to declined from its 0.5 magnitude to its current level of 1.66, a Betelgeuse right now -Elnath, the tip of the right horn of physical decrease in brightness of more than 50%! The RASC Taurus is magnitude 1.62. Handbook lists Betelgeuse as a variable having a range of 0.0 to 1.3 but it has now dropped below the lower limit given. For With the possibility, however slim, of a major event, it is not the last decade it has varied between 0.2 and 0.7 and only surprising that the media has latched on to this. Recent once, in Jan 2019, did it fade to magnitude 0.9. The current newspaper headlines read: “Is Betelgeuse Set to Blow?” or decline to 1.66 is unprecedented in close to 2 centuries of “Will Betelgeuse go Supernova?” etc. Astronomers are being monitoring! cautious saying that it is only a possibility, but remote. Still some less than responsible journalists are making the most of Check the brightness of Betelgeuse it. Please note that even if it does go boom, we are in no The next time you see Orion, check some nearby stars for a danger of cooking by radiation or having our atmosphere brightness comparison. The star in the other shoulder of stripped off since the star is about 650 light years away, -a Orion, Bellatrix, shines at magnitude 1.64 according to the nice safe distance to watch the show. To quote the article on Observer’s Handbook 2020. (All values given here are from page 3 above, a Betelgeuse supernova would “light up the the OH 2020). A quick check on Feb 8 showed the two at the sky like no other supernovae, and will last for months, same brightness although there was a slight reddish tint to visible in daytime, and cast shadows at night”. Betelgeuse. In the Belt of Orion, and , the left IAU/Sky&Tel chart left shows α-Ori at magn. 0 and circle around the symbol indicates a variable star.

Comparison Stars Magnitude Bellatrix 1.64 Alnitak 1.74 Alnilam 1.69 2.25 Saiph 2.07 Rigel -0.03 Betelgeuse = 1.66 (Jan 30, 2020 measurement)

Image above is Frank W.’s comparison images of Betelgeuse (left) and Bellatrix (right) taken Feb 3, 2020 with a Tec 140 mm refractor. Both are 4 second exposures at ISO 3200 with a Canon 6D. Each image is enlarged the same amount. Other than the colour difference, it is hard to say which is brighter.

Image left is from a crop from a photo taken Sep 29, 2019 on a hazy morning. The haze makes the brightness difference of Betelgeuse and Bellatrix stand out and is a fair indication of the pre-dimming appearance. Star in the trio at top is , 3.4 magn. Canon 6D, 12 mm SamYang at f/2.8, ISO 2500. (John H. photo). S G N Beetle-juice? Battle-goose? or Yad al-Jauza? Mar/Apr 2020 pg 5 From “Beetle-Juice” to “Battle-Goose”, What’s even worse is that detailed research reveals that What IS the Pronunciation? there have been several mistranslations of the original Arabic name, so we are using an incorrect basis right from the start. Wikipedia lists several pronunciations for Betelgeuse: Wikipedia says: ”The star's name is derived from the Arabic Yad al-Jauzā', meaning "the hand of Orion". The يد الجوزاء (biːtəldʒuːz/, or bit'-uhl-jooz (hard j soundˈ/ /ˈbɛtəldʒuːz/, or bet'-uhl-jooz Arabic letter for Y was misread as B by medieval translators, /ˈbiːtəldʒɜrz/ or bit'-uhl-jerz creating the initial B in Betelgeuse." So it should really be /ˈbiːtəldʒuːs/ or bit’-uhl-joos pronounced “Yettle-geeze”! Yikes!

The authoritative RASC Observer’s Handbook says it should Tony Flanders, a Sky&Telescope associate editor sums it up be pronounced Bet’ - tell - Juice with the emphasis on Bet, well: “The one thing worse than being pretentious and like the second item above and that is consistent in all the correct is being pretentious and incorrect.“ issues of the OH I have going back to the 1970’s. One final suggestion that clears the air is to call it "al'fuh Or- A little research suggests the name "beetle juice" came ee-on'-iss" i.e. Alpha Orionis! about because of the 1988 Tim Burton film, though that pronunciation may have preceded the movie. In any case, be careful to not repeat it three times.

Dust Causing Dimming? ESO press release: Using E S O ’ s Ve r y L a r g e Telescope (VLT), a s t r o n o m e r s h a v e captured new images of Betelgeuse’s surface showing not only the fading red supergiant b u t a l s o h o w i t s a p p a r e n t s h a p e i s changing.

At the time of writing Betelgeuse is at about 3 6 % o f i t s n o r m a l Paranal in Chile. “ESO’s Paranal Observatory is one of few brightness, a noticeable change. A team led by Miguel capable of imaging the surface of Betelgeuse,” he says. Montargès, an astronomer at KU Leuven in Belgium, has Instruments on VLT allow observations from visible to mid- been observing the star with ESO's Very Large Telescope infrared, to see both the surface of Betelgeuse and the since December, and among the first observations is a material around it. stunning new image of Betelgeuse’s surface, taken late last year with the SPHERE instrument.

The team also happened to observe the star with SPHERE in January 2019, before it began to dim, giving us a before-and-after picture of Betelgeuse. Taken in visible light, the images highlight the changes occurring to the star both in brightness and in apparent shape.

Like all red supergiants, Betelgeuse will one day go supernova, but astronomers don’t think this is happening now. They have other hypotheses.

“The two scenarios we are working on are a cooling of the surface due to exceptional stellar activity or dust ejection towards us,” says Edward Guinan, Astronomy professor at Villanova University, PA, has Montargès. “Of course, … a surprise can still happen.” measured the brightness of Betelgeuse over 25 years and the data from Sep 2019 is displayed above. The rate of dimming has decreased Montargès and his team used the VLT at Cerro recently, from Dec 7, 2019 (Julian date 2458825) to Feb 9, 2020. S G N Another new aurora type: “dunes” Mar/Apr 2020 pg 6

Amateur Aurora Watchers Do It Again press release University of Helsinki Working together with space researchers, Finnish amateur photographers have discovered a new Screen snap from video of “dunes” (finger-like structures left) auroral form. Named 'dunes' by the hobbyists, the above a regular curtain aurora. Video by Kari Saari phenomenon is believed to be caused by waves of oxygen atoms glowing due to a stream of particles released from the Sun.

In the recently published study, the origins of the dunes were tracked to a wave guide formed within the mesosphere and its boundary, the mesopause. The study also posits that this new auroral form provides researchers with a novel way to investigate conditions in the upper atmosphere. The study was published in the first issue of the high-impact journal AGU Advances. hobbyist observations and scientific methods coming together Unknown fingerprint appears in the sky to explain the waves. "It was like piecing together a puzzle or M i n n a P a l m r o t h , P r o f e s s o r o f conducting detective work," says Helin. "Every day we found Computational Space Physics at the new images and came up with new ideas. Eventually, we got University of Helsinki, heads a research to the bottom of it…” group developing the world's most accurate simulation of the near-Earth space and The phenomenon was photographed at the same time in both space weather that cause auroral Laitila and Ruovesi, southwest Finland, with the same detail emissions. The sun releases a steady flow observed in the auroral emission in both images. Maxime of charged particles, known as the solar Grandin, a postdoctoral researcher in Palmroth’s team, wind. Reaching the Earth’s ionised upper atmosphere, the identified stars behind the emission and determined the ionosphere, they create auroral emissions by exciting azimuths and elevations of the stars with the help of the atmospheric oxygen and nitrogen atoms. The excitation state astronomy software program Stellarium. This made it possible is released as auroral light. to use the stars as points of reference when calculating the altitude and extent of the auroral phenomenon. In late 2018, Palmroth published a book entitled 'Revontulibongarin opas' (‘A guide for aurora borealis Grandin found that the auroral dunes occur at a relatively low watchers’). The book was born out of Palmroth's cooperation altitude of 100 km, in the upper parts of the mesosphere. The with Northern Lights enthusiasts and the answers she wavelength of the wave field was measured to be 45 km. provided to questions about the physics of the phenomenon in the hobbyists' Facebook group. A total of seven similar events – where a camera had recorded the same even pattern of waves – were further identified from Thousands of magnificent photographs of the Northern Lights the 'Taivaanvahti' ('Sky Watch') service maintained by Ursa taken by hobbyists were surveyed and categorised for the Astronomical Association. book. Each auroral form is like a fingerprint, typical only of a certain phenomenon in the auroral zone. During the Unexplored region classification, hobbyists pointed out that a certain auroral form The part of the auroral zone where the Earth's electrically- did not fit into any of the pre-existing categories. Palmroth set neutral atmosphere meets the edge of space is an extremely aside these unusual forms for later consideration. challenging environment for satellites and other space-borne instruments. Palmroth says this is why it is one of the least By an almost unbelievable coincidence, just days after the studied places on our planet. book was published, the hobbyists saw this unusual form again and immediately informed Palmroth. The form appeared "Due to the difficulties in measuring the atmospheric as a green-tinged and even pattern of waves resembling a phenomena occurring between 80 and 120 kilometres in striped veil of clouds or dunes on a sandy beach. altitude, we sometimes call this area 'the ignorosphere'," she says. "One of the most memorable moments of our research collaboration was when the phenomenon appeared at that The dunes were observed precisely in that particular region of specific time and we were able to examine it in real time", says the auroral zone. The observed phenomenon guided the Northern Lights and astronomy hobbyist Matti Helin. researchers towards a middle ground between atmospheric research and space research, as the usual methodology of Waves newly revealed by the aurora space physics could not explain it alone. Investigations into the phenomenon were launched, with (con’t next page) S G N Another new aurora type: “dunes” Mar/Apr 2020 pg 7

" T h e d i ffe re n c e s i n brightness within the dune waves could be due to either waves in the precipitating particles coming from space, or in t h e u n d e r l y i n g atmospheric oxygen atoms," says Palmroth. "We ended up proposing that the dunes are a re s u l t o f i n c re a s e d oxygen atom density.”

Next, the team had to d e t e r m i n e h o w t h e variability in the density of the oxygen atoms caused by gravity waves in the atmosphere results in such an even and w i d e s p re a d fi e l d o f waves. Normally at the altitude of study there are many different kinds of gravity waves travelling in different directions at Above: Dune aurora may form in a 20 km layer as a gravity different wavelengths, which is why they do not easily form wave gets trapped between an inversion layer and the the even wavefields exhibited by the dunes. mesopause. See explanation left. (Graphic credit: Jani Närhi)

The Northern Lights illuminate a tidal bore Space researchers focus on the atmosphere The study suggests that the phenomenon in question is a Prior to this discovery, mesospheric bores were not observed mesospheric bore, a rare and little-studied phenomenon that in the auroral zone, nor have they been investigated via takes place in the mesosphere. The tidal bore phenomenon is auroral emissions. a wave common to many rivers, where the tide travels up the river channel. "The auroral zone as a whole is usually discounted in studies focused on the bore, as auroral emissions impair the Various types of gravity wave are born in the atmosphere and technique used to identify mesospheric bores," says then rise. In very rare cases, gravity waves can get filtered as Palmroth. they rise between the mesopause and an inversion layer that is intermittently formed below the mesopause. The inversion Traditionally, researchers specialising in the atmosphere and layer makes the filtered waves bend and enables them to space have largely investigated their topics of interest travel long distances through the channel without attenuation. separate from each other. This is because there are only a handful of known mechanisms of interaction between the Very rarely, a gravity wave rising up in the atmosphere can be ionosphere bathing in the precipitating electrons, and the filtered and bent to travel between the mesopause and an neutral atmosphere. inversion layer intermittently formed below the mesopause. The mesopause and the inversion layer are colder than the With the help of measuring devices operated by the Finnish other layers of the atmosphere. In the wave channel Meteorological Institute, the dunes were found to occur established between these two layers, gravity waves coming simultaneously and in the same region where the from below can travel long distances without subsiding. electromagnetic energy originating in space is transferred to Dune-shaped auroral emissions are created when solar wind the ignorosphere. charges the oxygen atoms surging through the channel. "This could mean that the energy transmitted from space to When the oxygen atoms in the bore collide with the electrons the ionosphere may be linked with the creation of the precipitating down upon the atmosphere, they become inversion layer in the mesosphere," says Palmroth. "In terms excited. When releasing this excitation, they create the of physics, this would be an astounding discovery, as it would auroral light. This is why mesospheric bores – a phenomenon represent a new and previously unobserved mechanism of thus far considered a very challenging subject of research – interaction between the ionosphere and the atmosphere." can occasionally be seen with the naked eye. Quetican Field of View by Doug Cunningham Mar/Apr 2020 pg 8 Iceland – A Country of Wonder, of Fire and Ice “Some say the world will end in fire, Some say in ice. From what I’ve tasted of desire I hold with those who favour fire. But, if I had to perish twice, I think I know enough of hate To know that for destruction, ice Is also great And would suffice.” “Fire and Ice” Robert Frost 1874 – 1963 There is a special island, Iceland, which has been shaped over time by Fire, Ice and Plate Tectonics. It is, without a doubt, a country rich in Earth Science wonders. It is located close to the Arctic Circle and positioned roughly midway between Greenland and the British Isles. It is a relatively small country, with a land area of only 103,000 sq.km, similar in size to that of mainland Nova Scotia and New Brunswick combined. Although Iceland has a small population of about 350,000 people, it hosts close to 2 million tourists a year.

From the editor: Astronomers looking for clear, transparent, steady skies, have to contend with clouds, of course, but there are other atmospheric effects that sometimes block our view. This includes smoke from forest fires and ash from volcanic eruptions. One of the first records of astronomical observing being affected in this way was from William Herschel in 1783 -a result of the eruption of the Laki volcano on Iceland.

Doug writes: To the west of the Vatnajokull glacier [more on pg. 10] is the famous Laki volcano, sitting alongside the Laki fissure, the site of the devastating volcanic eruption in June of 1783. In May, 1783, a series of earthquakes were felt to the west of Iceland’s Vatnajokull glacier. By June 8th, 1783, and continuing for the next 8 months, the Laki volcano, and the nearby Grimvotn volcano, were erupting violently in a single “volcanic tectonic episode”. A long fissure with 130 volcanoes opened up, and they were accompanied by “phreatomagmatic explosions, caused when the ground water meets rising basaltic magma. Volcanologists estimate that the explosive eruptions produced plumes that reached 15 kilometres into the air with global consequences. Laki Fissure and Volcano Chain located on the Mid-Atlantic A quote from Jon Steingrimsson and Keneva Kunz book: Rift in the SW part of Iceland (Web Archive) Fires of the Earth: the Laki Eruption, 1783-1784: 50% of cattle and horses died. Icelanders called it “Mist “This past week, and the two prior to it, more poison fell from Hardships”. the sky than words can describe - ash, volcanic hairs, rain full of sulfur and saltpeter, all of it mixed with sand. The snouts, These Laki Fissure volcanic eruptions drove enough ash and nostrils, and feet of livestock grazing on the grass turned bright aerosols high enough into the atmosphere that brilliant sunsets yellow and raw. The water went tepid and light blue, and gravel were observed throughout the northern hemisphere, and slides turned grey. All the Earth’s plants burned, withered and astronomical observations on deep sky objects were affected turned grey, one after another”. by the reduced transparency. Consider the following observations by William Herschel on M51, the Whirlpool For Iceland, the consequences were catastrophic! During the galaxy, using his 20 foot reflector, and made just after the Laki famine that followed the eruptions an estimated 25% of eruptions, and then compare those observations, with ones he Iceland’s population perished. Approximately 80% of sheep, made four years later with the same telescope. Quetican Field of View Iceland: Fire and Ice (Cont’d) Mar/Apr 2020 pg 9

From William Herschel’s Journal: From the editor: Herschel did much of his survey work with Observation on M51, 1783 Sept 20, Telescope 20 ft Reflector, the "20 ft reflector” mentioned here. In fact, he had 2 of these, 200X “Most difficult to resolve, yet I no longer doubt it. In one of 12-inch aperture and the other an 18.7 inch. Both had the southern nebula (NGC 5194), I saw several stars by the same focal length, 20 ft or 6100 mm. Long focal lengths various glimpses, In the northern (NGC 5195) also three or were used because the mirrors could more easily be ground four in the thickest part of it, but never distinctly. Evening into a spherical shape -accurate parabolas were beyond the very bad. technology of the day. As a comparison, the closest BAS telescope is the 5000 mm 12-inch Cassegrain obtained from U Then, about 4 years later he wrote: of G. That one is an f/16 while Herschel’s would have been Observation on M51, 1787 May 12, Telescope 20 ft Reflector about f/20. Another advantage of such a long focal length is 734X “Bright, a very uncommon object, nebulosity in the that eyepieces of reasonable focal lengths can be used. For center with a nucleus surrounded by detached nebulosity in the 200x Herschel quotes above, the eyepiece focal length the form of a circle, of unequal brightness in three or four would have been about 30 mm, a relatively easy task to grind. places, forming altogether a most curious object.” He also used an 8.3 mm eyepiece on the second observation - a bit trickier to construct.

Four images of Messier 51, the Whirlpool Nebula, at the (b) Lord Rosse's drawing of 1845, as published by Nichol. (c) same orientation and scale. Images are shown as negatives Rosse's drawing of 1850. (d) Modern electronic image to highlight fine detail. (a) John Herschel's drawing of 1833. captured with the CFH12K camera on the Canada-France- [I couldn’t find one of William’s drawings -ed] Hawaii Telescope.

Doug’s Iceland article continues: The reasons for Iceland’s popularity are not hard to find. Awaiting visitors is a warm and welcoming population, spectacular glaciers, extinct and active volcanoes, geyser fields, amazing waterfalls, whale watching, abundant sea birds, and displays of northern lights. Paula and I both agreed, Iceland is one of those exceptional places that, when you visit, as we did in September 2019, there just doesn’t seem to be enough time to experience all the natural wonders. We circumnavigated the whole island, getting a flavour for the country but not staying in any one place for a lengthy time.

Iceland sits above two active tectonic plates, the North Laki American plate and the Eurasian Plate. It displays the full complement of geophysical phenomena, including earthquakes and volcanic eruptions. To preserve and protect their spectacular natural, biological and geological heritage, the Icelandic Government has established three main National Parks, Pingvellir National Park, Snaefellsjokull National Park, and Vatnajokull National Park. We were fortunate to visit portions of all three. Quetican Field of View Iceland: Fire and Ice Mar/Apr 2020 pg 10

The first national park we visited was Pingvellir National Park (anglicized to Thingvellir). It is close to the capital city of Reykjavik and is one of the most popular tourist sites in Iceland. The park lies in a rift valley that marks the crest of the Mid-Atlantic Ridge (image right). On one side of this ridge is the North American Plate, and on the other is the Eurasian Plate. Over time, the motion of these tectonic plates have caused numerous faults, or cracks, in the area, and the largest one, called Almannagia, makes a small canyon. Each year hundreds of thousands of tourists walk down this canyon and see with amazement the rocks on one side from the North American Plate and, on the other side, rocks from the Eurasian Plate. Seeing this firsthand with your eye, and appreciating the geology with your mind, is wonderful! I climbed up both sides! We found the Snaefellsjokull National Park much larger and even more spectacular than Pingvellir. It is the home of the famous Snaefellsjokull stratovolcano, 1,446 metres in elevation, (shown in my photo left) which last erupted about 1800 years ago. The caldera at the top of this volcanic mountain was used by Jules Verne, in his 1864 science fiction novel, “Journey to the Centre of the Earth” as the entry point to a passage leading to the center of the Earth. This was Jules Verne’s first major science fiction novel, -a wonderful blend of imagination and 1860’s science. Verne’s descriptions of the adventures of the three main characters, Professor Otto Hardwigg, his nephew Harry, and a hired Icelandic guide, Hans Bjelke as they descend deeper into the Earth makes for a riveting adventure story. I had never read this particular Jules Verne book, but, after seeing the Snaefellsjokull Volcano Both Paula and I found the Vatnajokull National Park to be the myself, I bought the book at Chapters and, once I started most spectacular of Iceland’s national parks. We first saw the reading it, I couldn’t put it down. The 2012 printing has a Vatnajokull Glacier (image lower right) from its SE end above the new and inspiring “Introduction” written by Bear Grylls, town of Hofn, where I took the photo of the glacier descending a SAS military trained explorer who had also climbed from the mountains to the sea. The glacier covers 14 % of Iceland’s Mount Everest. At the end of the novel is an interesting land area, and comprises Iceland’s largest national park, and the second largest national park in Europe. The glacier is truly immense, covering 8,100 sq. km, and measuring between 400-600 metres in thickness. At its highest, it rises 2 km above the sea. Underneath the glacier lurk two live volcanoes: Baroarbunga, the largest, and Grimsvoten, the most active. The Vatnajokull glacier’s melt waters feed many rivers, resulting in many huge waterfalls, including Dettifoss, Europe’s largest volume waterfall (right).

Even the ground shakes there! Iceland is superlative! It is one of those surprising All photos on this countries, that transports visitors to a different world, an page by Doug amazing land of friendly people, northern lights, whales, Cunningham. and many geological wonders. Paula and I enjoyed the country and its people so much that we vowed to return again, and next time we hope to stay longer. S G N Sky Sights Mar/Apr 2020 pg 11 Mar 18: Mars, Moon, Jupiter, Saturn The last crescent Moon March 2020 appears with three planets in the dawn sky this morning. View Date GMT Event below is for 5:30 EDT locally. Mars has been slipping eastward 02 15:16 Aldebaran 3.3°S of Moon and passes Jupiter on Mar 20, Pluto Mar 23 and Saturn on 02 19:57 FQ Moon rises locally at 1:15 am EST Mar 31. It hangs around near Jupiter and Saturn for 2 weeks or so. By the end of March it reaches magnitude 0.8 just a bit 05 23:26 Pollux 5.2°N of Moon fainter than Saturn at 0.6. Jupiter is brightest at magn. -2.0. 06 21:08 Beehive 1.1°S of Moon The Moon slips past Saturn Mar 18, but next month in April, 07/08 Venus 2° from Uranus evening sky the planets are spread out more. See next page for details. 08 08:23 Regulus 3.8°S of Moon 08 03:00 Daylight Saving Time starts 08 12:00 Neptune in Conjunction with Sun (not vis.) 09 17:48 FM rises locally at 7:26 pm EDT (Daylight Time) 10 06:33 Moon at Perigee: 357 123 km 16 09:34 LQ Moon rises locally at 3:01 am EDT 18 08:19 Mars 0.7°N of Moon: Occn.(S. America, Antarctica) 18 10:18 Jupiter 1.5°N of Moon 19 00:04 Saturn 2.1°N of Moon 20 03:50 Vernal Equinox (10:50 pm Mar 19) 21 17:48 Mercury 3.6°N of Moon 24 02:00 Mercury at Greatest Elong: 27.8°W 24 09:28 NM rises locally at 7:51 am EDT 24 15:23 Moon at Apogee: 406 690 km Moon, Mars, Jupiter, Saturn 24 22:00 Venus at Greatest Elong: 46.1°E March 18 5:30 am Look East 29 21:52 Aldebaran 3.6°S of Moon April 2020 Date GMT Event Mar 24: Mercury at its Best Look to the dawn sky on Tuesday Mar 24 for an appearance of Mercury (magnitude 01 10:21 FQ Moon rises locally at 12:07 pm EDT 0.25), coincidentally the same date as the NM. Three 02 07:59 Pollux 4.9°N of Moon mornings earlier, on Mar 21, there is a nice thin crescent 5° 03 06:25 Beehive 1.3°S of Moon away (diagram below). Mercury is in quarter phase. 03 14:36 Venus 0.3°S of Pleiades 04 18:45 Regulus 3.9°S of Moon 07 18:08 Moon at Perigee: 356 909 km 08 02:35 FM rises locally at 7:35 pm EDT 14 22:56 LQ Moon rises locally at 2:49 am EDT 14 23:04 Jupiter 2.0°N of Moon 15 09:26 Saturn 2.5°N of Moon 16 04:33 Mars 2.0°N of Moon 20 19:01 Moon at Apogee: 406 463 km 22 06:00 Lyrid Meteors, 20/h, peak 1 am EDT, New Moon 23 02:26 NM rises locally at 6:39 am EDT 26 03:34 Aldebaran 3.8°S of Moon 26 10:00 Uranus in Conjunction with Sun (not vis.) 29 14:19 Pollux 4.7°N of Moon 30 13:18 Beehive 1.6°S of Moon 30 20:38 FQ Moon rises locally at 12:05 pm EDT See page 12 at bottom for BAS EVENTS

Apr 22: Lyrid Meteors peak at 20 per hour around 1 am Tuesday night/Wed morning. The advantage for this weak shower is that the Moon is about as new as it can get and will not interfere with any viewing. And the weather in April is starting to get a bit more balmy as long as we don’t get a late spring snow storm (or a cool shower or even overcast skies). Viewing is likely at the Fox Observatory. Sky Sights Mar/Apr 2020 pg 12 MERCURY is in the morning sky in March and Planets April and reaches elongation Mar 24. It is relatively easy to spot until the end of April. VENUS, reaches -4.5 at end of Apr and stays the predominant Evening Star. Look for it to pass through he Pleiades Apr 3. Photo op! MARS, (+1.2 to 0.4) is in morning skies with Jupiter and Saturn. Three planets group there as Mars passes below each of the other two in turn. JUPITER, is a morning planet and gradually brightens to -2.0. It is part of the three planet morning group along with SATURN, shining at 0.6 magnitude. URANUS, and NEPTUNE, are close to the Sun inMarch and April and difficult to observe. Dwarf planet, Ceres (8.6) stays in Capricornus east of Saturn and Mars into the spring sky. Asteroid, Vesta (7.4 fading to 7.8) travels through the Taurus and is near Venus in late April. PLUTO (mag. 14.3) stays Jupiter in Mar/Apr morning skies preceding sunrise. Finder charts for Pluto in 2020 are now on the BAS website.

Table below gives the sunrise/sunset times and the Sun’s altitude for dates in March and April. The Sun continues heading southwards in our sky. The moon phase dates are in the Astronomy Events listing pg. 11 along with moonrise times for Owen Sound. Outside of the Bruce-Grey area, check https:// www.timeanddate.com for Moon and precise Sunrise/set times for your location. Apr 3: Venus and Pleiades: Venus passes through M45 on Apr 3 (-4.7) outshines the cluster, -a tricky shot. You could try longer and it is within a degree or so of the cluster from April 1 to 5. The exposures of M45 before Venus appears and then “paste” Venus planet and cluster are well above the horizon even at 9 pm on in later with Photoshop. This is cheating a bit, but it will provide a those dates. This is a spectacular photo op, but the nebula more realistic view that one would see with binoculars or a around M45 needs a longer exposure while the bright planet telescope with wide field eyepiece.

Sunrise/set times: Owen Sound 44°35‘N 80°55’W Times in Eastern Daylight Time (EDT)

Date Rise Noon altitude Set Mar 10 7:44 am 41.7° 7:24 pm Mar 20 7:25 am 45.7° 7:36 pm Mar 30 7:07 am 50.0° 7:50 pm Apr 10 6:47 am 53.7° 8:03 pm Apr 20 6:30 am 57.3° 8:15 pm Apr 30 6:14 am 60.5° 8:27 pm Data from www.timeanddate.com S

E W

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Apr 14 to 16: Moon and Planets The morning sky is the scene of the planet action in mid-April. The crescent Moon Next BAS Meeting Mar 4, 2020 @ Bailey Hall passes Jupiter, Saturn and then Mars in the dawn sky as seen around 4 am in the diagram above. On Apr 14, the last BAS Events in Mar/Apr quarter Moon is about 7° west of Jupiter, on Apr 15 the Moon is about half as far from Saturn and on Apr 16, it is Mar 4: BAS meets in Bailey Hall OSDSS 7 pm. about 3° from Mars. At this time, it os decidedly more Mar 21: Dark of Moon viewing at Fox Obs. Messier Marathon crescent-shaped, being about 5 days before new. Until the Mar 28: Coffin Ridge star talk/viewing. Contact John H. if you can help summer when Mars moves away from Jupiter and Saturn, Apr 1: BAS meets at Bailey Hall OSDSS 7 pm Astronomy Trivia Night the crescent Moon makes a visit to the sky near these three Apr 25: Dark of Moon viewing at Fox Obs. Messier Marathon (part 2) planets about mid-month. May 2: Coffin Ridge star talk/viewing. Contact John H. if you can help SGN : Orion the Hunter Mar/Feb 2020 pg 13

Orion (Ori) α−Orionis - Betelgeuse δ−Orionis - Mintaka DOUBLE STARS η−Orionis - Algjebbah β−Orionis - Rigel ε−Orionis - Alnilam Mag Sep(s) Remarks κ−Orionis - Saiph γ−Orionis - Bellatrix ζ−Orionis - Alnitak β 0.1-8.0 9 White-Orange. λ−Orionis - Meissa δ 2.5-6.9 53 White-Lilac. ζ 2.0-5.5-10 2.5-57 Yellow-Blue. Orion is generally considered to be the most beautiful and imposing η 3.6-5.0 1 constellation in the heavens. It is easily recognized; the four bright θ 5 thru 11 - At least 7 stars in this multiple stars forming a large rectangle and the three second-magnitude system; lies in the heart of the stars, equally spaced and forming a straight line (Belt of Orion) Great Nebula aka the Trapezium enclosed by the rectangle, are a delight to the eye. No other ι 2.9-7.3-11 11-50 In a fine field constellation has so many bright stars. Compare the colours of λ 3.7-5.6-10.9-11.8 4-29-78 Yellow- Magenta; in fine field; Betelgeuse, a giant red star, and Rigel, a brilliant blue-white star. quadruple Rigel has a magnitude of 0.3 and is the 7th brightest star in the sky; ρ 4.6-8.3 7 Yellow-Blue. Betelgeuse, a variable, has dropped to magnitude 1.5 and lost its σ 4.0-10.3-7.5-6.3 11-13-42 Grey-White-Blue-Red; normal rank of 12th in brightness. [See pg XXX for more]. Orion is in beautiful quadruple a portion of the sky that contains seven of the 20 brightest stars in 23 5.0-7.1 32 the heavens; these are to be found in Orion, Auriga, Gemini, Taurus, 33 6.0-7.3 2 Canis Major and Canis Minor [the Winter Hexagon -ed]. Σ627 6.3-7.0 2 Striking. Σ747 5.6-6.5 36 There are two famous nebulae in Orion; one, the Great Nebula Σ750 6.0-8.0 4 [Orion Nebula, M42], is visible to the naked eye. It is the prototype Σ795 6.2-6.2 1.5 of the diffuse nebulae; a great cloud of cosmic dust 26 light years in Σ816 6.2-8.7 4 diameter and 1,625 light years away. θ−Orionis marks the center of Σ855 5.8-6.8-9.0 29-119 Triple. the Great Nebula; viewed through binoculars, the star seems to be enveloped in a hazy field that marks the nebula's presence. Even in MESSIER OBJECTS a small telescope, the Great Nebula is an awe-inspiring sight. The Mag Remarks other famous nebula is the so-called "Horse's Head" Nebula, M42 Diffuse Nebula. The "Orion Nebula” [Barnard 33] a dark nebula silhouetted against a glowing cloud of M43 Diffuse Nebula. cosmic dust in the shape of a horse's head. This remarkable object M78 Diffuse Nebula. is not visible to the naked eye; -long photographic exposures are Objects of Interest in Orion required to show its details. The darkness of this cosmic cloud is - Long period (372 days) variable, max. magnitude 6.3. due to the fact that there are no nearby stars to illuminate it. σ , θ B33 - -faint, difficult to see, needs large scope. and ι−Orionis mark the Sword of Orion. δ-Orionis, the northernmost star in the Belt of Orion, lies almost exactly on the celestial equator. The Belt stars serve as valuable pointers; the line through them extended to the southeast points to Sirius and to the northwest, to Aldebaran in Taurus. U

Σ795 *Σ816

The Trapezium Cluster at the heart of M42 consists 23 Σ627. 33 of four easily observed stars labeled A thru D as in Σ855 the Robert Burnham diagram above. Starry Night gives a magnitude for A of 4.96, B is 7.46, C is 5.06 and D is 6.37. Recently A and C have been found to be very close double stars and B is quadruple! Burnham’s diagram also shows stars labelled E, F B33-* and G. The first two are about 11th magnitude and Σ750 G is about 16, requiring a telescope 16” in diameter or larger. The entire cluster is about 4 ly across and contains about 1000 young stars. The large energy Σ747 released powers the emission from the nebula that surrounds them. Imagine 1000 stars in the space between our Sun and α-Centauri! Awesome! S G N The Miscellaneous Page Mar/Apr 2020 pg 14 BAS Member Loaner Scopes Solar H-alpha scope now available. Our Lunt solar scope can be borrowed by BAS members and it SGN is waiting at the Fox! Contact John to get your hands on it. We now have a suitable mount for it as well. A short training Classified session will be provided on pickup. Ads Section Several Dobs available. One 12-inch dobsonian loaner telescope is available for free loan to members. Other telescopes are also available. Contact (Also on our website) John H. or Brett T. for availability. Scopes come in and out so keep checking with John or Brett if you are interested in borrowing a telescope.

FOR SALE: 12.5 inch f/6 Dobsonian telescope Homebuilt by experienced telescope maker in 1980. See Sep 2014 FOR SALE: 2-inch Filters: SGN pg 9 for build details. Truss tube design with full thickness - Antares 2” filter 23A (light red) ($35) Coulter mirror -one of their best, recently re-aluminized. Focuser and - Antares 2” filter 80A (blue) ($35) secondary mirror/spider is a Novak unit. Alt-azimuth mount (3/4-inch - LP-2 Narrowband (light poll. filter) ply) is a nice wood grain finish with coating of Varathane. This is a for 2”eyepieces (asking $200 or BO) large telescope and probably would be happy in a relatively - contact [email protected] permanent location, but is portable if you have lots of trunk space. - ALL OFFERS CONSIDERED Loading into and out of a car trunk is easier with two people. Can be seen at the Fox Observatory. Asking $789 but willing to negotiate. FOR SALE: Contact John H. at 519-371-0670 or [email protected]. Contact [email protected] for any of these items.

See the complete list on BAS website STUFF FOR SALE page. Two-inch mirror diagonal plus adapter for C-8’ or Meade SCTs $80

Minolta 35 mm film camera XG-SE, plus Makinon 80-200 mm f/4 zoom lens. Asking $20

Generic O-III nebula filter Manfrotto Tripod model Set of 4 Meade Research grade threads onto 1.25” ep $50 074 Controls on three Orthoscopic 1.25” eyepieces. Meade full aperture axes, HD $125 (28 mm, 16.8 mm, 10.5 mm, 4 mm) glass solar filter (9.25” Some of the best planetary eyepieces ID) -orange/yellow image made by Meade. (price in 1980 was (equivalent to Thousand $145 ea.) $100/set or $30 each. Oaks Type 2 Glass filter) asking $40

Meade 2x-3x variable Barlow (1.25”) asking $20

More Thanksgiving Aurora S G N The Milky Way of Machu Picchu Mar/Apr 2020 pg 15

Image above was taken Apr 5, 2011 in Atacama and shows Inca Astronomy. The two llamas are to the right and the two much of the southern Milky Way including the dark dark spots (the first is the Coalsack) upper right are Yutu and constellations up to Hanp’atu the Toad. Get your bearings Hanp’atu the Toad. Canon 50D image, 64 s exp. 10 mm lens from the brightest glow of stars just left of centre and find the at f/2.8, ISO 1600. This 2011 Chile trip was organized by Sky upside down Dark Horse above it. That is Atoq the Fox in News and included Terry Dickinson and Alan Dyer.

Inca “Dark” Constellations In addition to the more normal join-the- bright-stars constellations, Inca astro- nomy included the dark nebula that are more prominent in the S. Milky Way.

These included: Yutu -the Tinamou (two of them), a clumsy ground bird similar to a partridge; (lower left and centre)

Atoq -the Fox; (the tail is part of the Dark Horse of Sagittarius)

Uruchillay -the llama; (none of the following can be seen in our skies)

Urallamacha -the baby llama; Hanp’atu -the Toad;

Mach’acuay -the Serpent, the most important dark constellation.