The Reflector Newsletter of the Peterborough Astronomical Association What It’S Like on a TRAPPIST-1 Planet

Volume 16 • Issue 4 April 2017 ISSN 1712-4425 peterboroughastronomy.com twitter.com/PtbAstronomical The Reflector Newsletter of the Peterborough Astronomical Association What It’s Like on a TRAPPIST-1 Planet

This artist’s concept allows us to imagine what it would be like to stand on the surface of the exoplanet TRAP- Marcus Woo PIST-1f, located in the TRAPPIST-1 system in the constellation Aquarius. Credit: NASA/JPL-Caltech/T. Pyle (IPAC) ith seven Earth-sized on, the star would appear several the worlds are so close to their planets that could times bigger than the Sun. You star, they’re tidally locked so that harbor liquid water would feel its warmth, but because the same side faces the star at all Won their rocky, solid surfaces, the it shines stronger in the infrared, times, like how the Man on the TRAPPIST-1 planetary system it would appear disproportionately Moon always watches Earth. If might feel familiar. Yet the system, dim. you’re on the planet’s dark side, recently studied by nasa’s Spitzer “It would be a sort of an orang- you’d be enveloped in perpetual Space Telescope, is unmistakably ish-salmon color — basically close darkness — maybe a good thing if alien: compact enough to fit inside to the colour of a low-wattage light you’re an avid stargazer. Mercury’s orbit, and surrounds an bulb,” says Robert Hurt, a visual- If you’re on some of the farther ultra-cool dwarf star — not much ization scientist for Caltech/IPAC, planets, though, the dark side bigger than Jupiter and much a NASA partner. Due to the lack might be too cold to survive. But cooler than the Sun. of blue light from the star, the sky on some of the inner planets, the If you stood on one of these would be bathed in a pastel, orange dark side may be the only comfort- worlds, the sky overhead would hue. able place, as the light side might look quite different from our own. But that’s only if you’re on the be inhospitably hot. Depending on which planet you’re light side of the planet. Because See “TRAPPIST-1” on page 20 2 • peterboroughastronomy.com President’s Message Earth Hour want to thank you Rodger Forsyth, seems to me that people were amazed by Rod Forsyth, Boyd Wood, Paul Ward what they saw and by the explanations you I and John Cameron for making our gave them. I feel very happy with the role “Earth Hour” a successful event. From 8 pm that our paa plays in our community. I to around 11 pm we had a beautiful night, invite more members to join us for our next and clear skies. According to John, we had community astronomy event. a head account of more than 100 people. Jaime Morales It was a great experience for our guests, it

Letter from the Editor Spring is In the Air

ow that we are officially into in Sunspot, NM high up on Sacremento spring, perhaps the weather will Peak. N cooperate for your viewing plea- John Crossen entertains us with a variety sure. By all accounts, the Earth Hour pub- of topics include the highlights of the April lic viewing on March 25th was splendid. sky, accessible astronomy gear, living on Unfortunately, our usual correspondent Mars, and putting the discovery made by for Earth Hour was on a different conti- TRAPPIST-1 in context. nent at the time. In lieu of his report we As usual we have exemplar images from have reprinted a special article from Inside John Chumack and Brian McGaffney in our Science, an editorially-independent news Photo Gallery. service published by the American Insti- Till next month. tute of Physics. The article outlines how Phillip Chee astronomers are helping to encourage the Editor, The Reflector reduction of light pollution, one of the side- effects observed during Earth Hour events. Sean Dunne and Dean Shewring collabo- rated on the goings on of the solar viewing The Reflector observation held at Mapleridge Observatory last month. If you missed it, we have photo- The Reflector is a publication of the Peterborough Astronomi- cal Association (P.A.A.) Founded in 1970, the P.A.A. is your local graphs. group for astronomy in Peterborough and the Kawarthas. Rick Stankiewicz presents Part III of his www.peterboroughastronomy.com • [email protected] Phone: 705.748.2038 New Mexico road trip. This time he visists Club Mailing Address Jaime Morales, President the National Solar Observatory, next door Peterborough Astronomical Association neighbour to the Apache Point Observatory 1587 Redwood Drive Peterborough, ON K9K 1N9 Vol 16 • Issue no. 4 • April 2017 • 3 The Reflector Astronomers Encourage Cities to Shield Outdoor Lighting

Access to a dark night sky is a universal human right, says the American Astronomical Society. Image Credit: Abigail Malate, Staff Illustrator, American Institute of Physics. How to help reduce light pollution Ramin Skibba, Contributor/Author in three steps, following Inside Science – Our home galaxy, the Milky recommendations from the AAS. Way — that iconic stream of stars cours- Light pollution from street lights, lit ing across the night sky — cannot be seen billboards and other outdoor light fixtures by one-third of humanity and 80 percent affects many people and wildlife species, of Americans. As the artificial glow from nocturnal and diurnal alike. “It has huge ef- towns and cities increases every year, and fects on public health, the environment and starry nights become unfamiliar to many, certainly for astronomy,” said James Lowen- astronomers and dark-sky advocates are thal, an astronomer at Smith College in pushing to reduce light pollution — starting Northampton, Massachusetts. Astronomers with changes to outdoor lighting. at observatories can see the effects of light The American Astronomical Society glow from a city hundreds of miles away, to passed a resolution at their annual meeting their dismay. in Grapevine, Texas this month, “affirming Many cities transformed their outdoor that access to a dark night sky is a universal lighting following the recent revolution in human right, making quality outdoor light- light-emitting diodes, or leds. Blue leds ing a worldwide imperative.” earned three engineers the Nobel Prize The organization also endorsed a set of in Physics in 2014, since blue was the last recommendations for outdoor lighting. In color needed to make white leds. The new short, “shield the light, dim it, and use red- lights are now ubiquitous in smartphones, der, warmer colors,” said Lori Allen, direc- computer screens and energy-efficient light tor of the Kitt Peak National Observatory in bulbs. Arizona. See “Three Step Solution” on page 16 4 • peterboroughastronomy.com PAA’s Sunny Ways

Peterborough Astronomy Association members gather in the backyard of Brian Colville’s Mapleridge Observa- tory on Sunday 19 March 2017.

Sean Dunne and Dean Shewring n Sunday, March 19th, the scope and camera more clearly — just like paa had a marvellous solar ob- the old view cameras. Apart from the scopes serving session at Brian Colville’s there was a lot of really great discussion. OMapleridge Observatory near Cambray The accompanying photos from Sean (west of Lindsay). It was the first observing were taken with his Sony α6000 with a 2× session which the weather has allowed in 5 tele-extender at the prime focus of Brian’s months — the last was in October. It was a double stacked Lunt 80 mm solar scope. beautiful sunny day with almost no wind; Exposure was 1/25s @ iso 1600. A special just about ideal for observing. thank you to Brian for his help with the From the paa we had Rodger Forsyth, photos, as we had a difficult time attaching Ken Sunderland, Dan Hamilton and his the camera and getting it to focus, and for wife, Geoff Porter, Karen Monahan, John hosting this event. See the next page for a Cameron, Brian Colville and Sean Dunne. couple of examples. Brian’s family plus some friends came by for a look. We used three scopes. Sean set up the Williams 80 mm in white light, Rodger set up the Club PST and Brian had the dou- ble stacked 80 mm Lunt. We think Ken used some binoculars as well. Ken also brought a large towel that we used to drape over our heads so that we could see the image in the continued on next page Vol 16 • Issue no. 4 • April 2017 • 5 The Reflector continued from previous page 6 • peterboroughastronomy.com New Mexico Adventures Part III: Walking Tour of the National Solar Observatory (NSO)

Figure 1. Sunspot Astronomy Vistor Center and Gift Shop. Photo by Rick Stankiewicz.

Rick Stankiewicz fact, even the drive up was interesting be- cause a town called Cloudcroft (26 km from ur adventures continue as Sunspot) is where a scaled model of the we explored New Mexico this past solar system starts, with Cloudcroft being January. In last month’s The Reflector the orbit of Pluto and all the planets inward Owe explored the Apache Point Observatory are marked along the Sunspot Highway (apo) and this month we take a closer look (NM#6563) until you reach the nso Visitor at the facility next door to the apo, the Na- Center, which would be the location of the tional Solar Observatory (nso). The nso is Sun. At this scale, the 4.5 billion kilometres located not a kilometre away from the apo, from Pluto to the Sun fit in the space of still on Sacramento Peak at an elevation of 26 km. This equals a scale of 1 to 250 million. 9,200 ft (2,800m). This location is also called In other words, if the Sun was 5.5 m, then Sunspot, NM. The site was chosen in 1947 the Earth would be 5 cm. because of the dry air, isolation from major The grounds of the nso are setup as a self air pollution and lots of sunshine, all the guided walking tour. There are free maps right conditions for studying the Sun. available and a paved walkway leads you One of the downsides to travelling in the from the visitor centre to the five observa- off season is that hours of operations are tories. At each is located a plaque that tells reduced or non-existent. Such was our case you about what each facility houses and a when we arrived at the Sunspot Astronomy bit of their history. Most of these domes are and Visitor Center/Gift Shop (Figure 1) at not available to the public, nor are the labs, noon on a Thursday in the middle of Janu- shops and offices. These are reserved for the ary only to find their “off season” hours, are research scientists, engineers, technicians weekends only (9 to 5). Luckily there was and support staff. Plus there are scientists more to see than just the visitor centre. In continued on next page Vol 16 • Issue no. 4 • April 2017 • 7 The Reflector continued from previous page from other observatories and universi- ties around the world who come here to use these facilities. The nso operates solar facilities not only at this location, but also at Kitt Peak in Arizona and is run by a consor- tium of universities (mostly U.S.) and few other institutions. On our walk, the first building we came to was the John W. Evans Solar Facility (Big Dome). This cone-shaped dome (Figure 2) used to house two telescopes, both a 16” coronagraph and 12” coelostat or heliostat. This facility was designed to mainly study the corona (faint outer layer of the Sun). The coronagraph has a disk that blocks the solar disk (like an eclipse) to allow study of the corona. Scientists could also study any other solar feature that protrudes beyond the solar disk (flares and prominences). The Figure 3. Richard B. Dunn Solar Telescope. Photo by heliostat allowed the reflection of the Sun’s Rick Stankiewicz. rays to be directed off-axis by a flat mirror, The primary mirror is 163 cm (64”) in di- into a solar telescope. Operating since 1952, ameter. The light is then focused and sent these telescopes ceased operation in Octo- up the tube to ground level where optical ber of 2015. experiments can be performed. The design of this telescope is stranger than “friction” because even though the whole assembly is longer than a football field and weighs more than 250 tons, it is suspended from a 10 ton mercury float bearing, that is hanging from three bolts at the top of the Tower that are only 76 cm (3”) in diameter and yet can be turned with ease. This telescope has been operational since 1969 and has been used to study granulation, sunspots, faculae, mag- Figure 2. John W. Evans Solar Facility (Big Dome). Photo netic fields, filaments and solar flares. by Rick Stankiewicz. Next up the hill was the Improved Solar Further up the path is the imposing Optical Observing Network (isoon) Build- Richard B. Dunn Solar Telescope. This odd ing (Figure 4). Though the telescope housed looking, but impressive structure is strang- here was dismantled in 2014 and reestab- er than you think. What you see behind my lished at the Kirtland AFB, this building, wife and I (Figure 3) is a 41 m (136’) struc- when operational, enabled autonomous ture, but there is another 72 m (228’) below hydrogen-alpha study of the Sun for space ground you can’t see. It reminds me of an weather forecasts. It was a “desktop ob- iceberg in that way. When operational, servatory” because it could be controlled there are two mirrors at the top opening remotely. that direct the sunlight down a vacuum Next to this abandoned building is the tube in the centre of the telescope to the Scenic Lookout and it is the best view we primary mirror 57 m (188’) below ground. See “NSO” on page 14 8 • peterboroughastronomy.com April’s Constellations Are Invading the Night Sky

John Crossen s the Sun sets in in the west, Hercules the Strong Man and Bootes the Herdsman are well up Ain the east. Can’t find the Big Dipper? It’s overhead at this time of year, so look up, up, farther up. Also known as the Great Bear, the Dipper is almost straight overhead. High in the southern sky is Virgo the Virgin as is Leo the Lion, though a bit further west. Those are the major constellation for the season. If you’re a newbie to the hobby, they are the first you’ll want to learn. A good plani- sphere is an excellent tool for doing so. Also A simple Moon map and a clear night will infect your a current issue of SkyNews will do the same. curiosity. Shown here are the seas or mare in Latin. You’ll find the latter at Chapters in Peter- They are the dark areas on the lunar surface that were borough. formed by lava flows from huge impact craters. Moon-a-tics will welcome April with a growing crescent Moon. By April 3 our piece. M13 is estimated to have over one nightlight will have bloomed to its first million stars within its gravitational grasp quarter phase. Because the Sun is striking it and M92 isn’t far behind. at an angle, the craters and mountains are Are you goofy for galaxies? Step right up. emphasized by their long shadows. There are five in Leo the Lion and galaxies By April 11 we are lit by the Full Moon. by the cluster in Virgo. A half dozen call the While you might think that this is a good Big Dipper home and there are plenty more phase for observing our celestial dance for the expert observer to view. partner, you’d be wrong. At Full Moon If all of the above is unfamiliar to you, phase it is lit straight on. So there are no here are some suggestions. For books Ter- shadows and all the detail on the Moon’s rence Dickinson’s NightWatch and H.A. surface goes flat. Rey’s The Stars: A New Way to See Them, are From the 11th on the Moon rises later tops in my books. They’ll give you excellent each night and on April 19 it will be at Last star charts to work from. You’ll find them Quarter phase. Again, the Sun is lighting it online at Amazon or in Peterborough at from an angle and the shadows cast make Chapters. the lunar detail “pop”. All of this is most Also of great use is the planisphere or star evident when viewing through a small tele- wheel. It’ll show you the constellations for scope. However binoculars will do. If you each of the four seasons along with when can get your hands on a lunar map, even and where to look. To buy one you’ll need to naked eye observing works. access an astronomy store and do a bit of Deep sky observers (those folks with phoning around. Happily all of the stores bigger telescopes) will welcome the return have toll-free lines. So go online and look of some favourite targets. Hercules brings up one. Toronto has two, there’s another in with him the magnificent globular star Bolton and Ottawa has yet another. A little clusters known as M13 and M92. Both are a research up front will make things easier virtual explosion of stars in a scope’s eye- down the road. Vol 16 • Issue no. 4 • April 2017 • 9 The Reflector What’s the Best Gear for Acessible Astronomy? If you enjoy viewing deep sky objects like galaxies, nebulae and star clusters the Orion Starblast 6-inch is for you. Sit down and en- joy spectacular tours of the Moon’s craters, Saturn’s rings and the moons of Jupiter. Plus its six inches of light-gathering capa- bility puts all the brighter deep sky objects within view. There are other options worth consider- ing, too. Sky-Watcher, Celestron and Meade also have an array of table-top reflectors. These cute little tuskers are cheap, por- table and put the eyepiece within easy reach — plus they don’t cost a small fortune. We’re talking well under $300 in most cases. Table-top telescopes may have been designed for So from my big observatory I moved to younger observers, but they work beautifully for the a much smaller one along with my appro- older set. And they’re ideal for anyone with mobility is- sues. A small table and folding chair are all you need. priately smaller scope. It’s mounted on a permanent in-ground pier. My observing John Crossen chair is on rollers — standard office issue sk an expert — me. I never from Staples. My observatory is actually a thought it would happen, but as the converted garden shed, so I have shelving, years marched on, my ability to walk drawers, a computer bench and a heater. Agot out of step. I also lost my sense of bal- It’s a tad cramped, but like I said earlier, I’m ance and wound up waddling like a drunk- an astro-nut. You can get by nicely with less. en duck. Add in a broken back and you’d Right now I can waddle a short ways, but think it was time to cash in my astronomy to navigate long stretches I need a rollator. chips — but not so quick, you’re talking to a I call it “handicapped lite”. Someday I may certified astro-nut. find myself in a wheelchair. In that case, I’ll No longer could I zip up the ladder to have to adapt my gear again. reach the eyepiece of my 16-inch monster Technology is adding new possibilities scope. And walking over uneven ground in every day — or should I say night? Some the dark was a major fall-down-go-boom well-heeled stargazers have remote control challenge. So it didn’t take a stroke of telescopes with video cameras instead of genius to arrive at the conclusion that my eyepieces. They sit indoors and watch galax- future observing would have to done from ies, planets and star clusters on computer a chair. I needed a scope where I could just monitors in air-conditioned comfort. sit down and look up. No tall tripods need Don’t let a mobility handicap keep from apply. looking up. Surprisingly there are a number of scopes that fit that bill. They’re called table- top telescopes. At first glance they may look like kid’s toys, but they are far from being anything close to that. 10 • peterboroughastronomy.com PHOTO GALLERY

Venus Approaching Inferior Conjunction

The planet Venus approaching inferior conjunction on 10 March 2017 at 21:57 U.T. from my backyard Observatory in Dayton, Ohio USA. This is a Daylight shot, the sun was still above horizon at time of capture. It looks very Large through most telescope eyepieces, because it is very close to Earth right now. The thin crescent phase is very noticeable in a little 50mm finder scope, so if you set your binoculars on a tripod, steady, you may be able to detect the crescent shape, even in daylight. When observing Venus during the day be careful not to accidentally point at the Sun. I was observing Venus between 3pm and 7pm in the South Western sky. Try to put the Sun behind a building. Without the glare of the blinding Sun, this may help you spot Venus. Venus details: • Phase = 0.080, The Diameter is 54 arc seconds • 8 inch SCT Scope and QHY5IIL CCD Camera, & 1200 frames stacked in Registax 6. An explanation and diagram of what is going on during Inferior conjunction can be found here http://astronomy.swin.edu.au/ cosmos/I/Inferior+Conjunction Best Regards, John Chumack www.galacticimages.com Vol 16 • Issue no. 4 • April 2017 • 11 The Reflector

Stephan’s Quintet

The attached is a wide field hi res image (means you can zoom in with detail) of Stephan’s Quintet and the Deer Lick Cluster. I had to use this field to capture both clusters ( the group at 12 o’clock and the group at 4 o’clock (this group know as the Deer Lick Cluster). The Quintet group at 12 o’clock is on the verge of collision and is in the high emission region. The cluster grouping is in the con- stellation Pegasus. One can count the numerous number of other distant galaxies in this image. This image was taken last week (November 2016) during extreme poor hazy night skies. The original image was 32-bit, but had to be reduced in resolution for email purposes. Brian McGaffney 12 • peterboroughastronomy.com Little-known Facts About Planet Earth to Space You Out

People are living longer and multiplying at the same time. We could reach the 10 billion mark by 2050 per some estimates. By then you may need a mortgage to buy a Big Mac. Illus: Earth from Mars courtesy NASA.

John Crossen ing capacity the most people dear old terra firma can handle is estimated at 10 billion. he other planets in our solar Genetic modification has given us en- system are so different from our hanced crop production over the years, but warm and cozy home that just about there is a limit to how much food Earth can anythingT I can say about them rings the produce. Then there’s the new oil of tomor- “Wowie Bell” on the “Amaze-O-Meter”. But row — water. I hate to think of the results we’ve got some equally amazing things hap- supply and demand will have on our future pening right here at home. You just should population. Perhaps “Go forth and multiply” dig a little to find them. should apply to a new planet that we haven’t Let’s start a trip to an area of the Indian worn out yet. Ocean known as the Lonqi or Dragon’s The Earth/Sun relationship has become Breath region. The area is 2.8 km/1.8 mi much stronger in the last few years. Thanks deep and has chimney spires rising two to lower costs and government support, the stories above the ocean floor. A research use of solar power made impressive gains team sent to study the vents discovered in 2016 in the United States. The first three six new species of life known only to this quarters of this year have already seen more area and its super-hot vent system. So, you new installations of more solar panels than can add another 6 critters to the 8 million, the entirety of 2015. A Green Tech Media 700 thousand species we already share the study shows that in the third quarter of 2016 planet with. alone will see a whopping 191 percent rise Ever wonder how many people currently in installations from the same quarter last inhabit our planet? The answer is just over 7 billion. But given our current crop produc- see “Little Facts” on page 19 Vol 16 • Issue no. 4 • April 2017 • 13 The Reflector What’s Ccool About the 7 New Exoplanets and What’s Not?

John Crossen ow that the initial excitement about the 7 trappist exoplanets has died down, let’s take a better Nlook at what we know about “The Magnifi- cent Seven”. It’s quite a discovery and has taken the resources of a global and extrater- restrial network of astronomers. Let’s look at what we know to date. For starters the exoplanets are orbiting a red dwarf star. This is a star that is much smaller than our Sun. In fact it is just big enough to support nuclear fusion. That’s the process that gives a star its energy and heat to maybe provide the necessary envi- ronment to support life. The three innermost exoplanets (trap- pist b, c and d) are too close to their home star to be habitable. trappist b takes just 1.5 Earth days to orbit the red dwarf star it calls home. So if you like birthdays, trappist b is for you. trappist c has a 2.4 day orbital TRAPPIST Observatory. Trappist-1 takes its name period and trappist d grinds out its orbit from the observatory that discovered it. The observa- in 4.05 days. tory takes its name from the technique used to find exoplants - Transiting Planets and Planetesimals Small Unfortunately all three of the innermost Telescope. planets would be blazing hot. So any life forms on them would bear nothing in com- the Sun. That’s on a proportional basis. mon with any species on Earth. trappist h has been deemed too far from trappist e, f and g are another story. its star to harbour life. In other words it’s They lie within the habitable zone. The a frozen world. Then again the Arctic and habitable zone is defined as an area warm Antarctica have been found to harbour life enough for water to remain in a liquid forms that range in size from microbes to form. Given that water is an essential in- penguins. gredient for carbon-based life forms, that’s Astronomers have known about trap- the place on which to bet your hard-earned pist-1 (the star’s astronomical name) and shekels. its 3 innermost planets since May of 2016. Their orbital periods vary from 6 days Continued study by Earth-based telescopes for trappist e, 9.21 days for trappist f and and the Spitzer Space Telescope were 12.35 days for trappist g. All three of these responsible for the most recent catch of 4 exoplanets are roughly the same size as more exoplanets. Earth. And as an added plus, trappist e re- One of the coolest things about the trap- ceives about the same amount of warming pist-1 system is the fact that you could see light from the red dwarf as Earth does from See “Exoplanets” on page 17 14 • peterboroughastronomy.com continued from page 7 NSO

Figure 4. Improved Solar Optical Observing Network Figure 6. Hilltop Dome. Photo by Rick Stankiewicz. (isoon) building. Photo by Rick Stankiewicz. had of the valley between the Sacramento telescope to observe the limb (edge) of the and San Andres Mountain Ranges. From Sun. To house this telescope and its mount, our panoramic view (Figure 5), you could they ordered a grain bin silo from the Sears see a large patch of white in the distance. and Roebuck catalogue and modified it with This is not snow, it is sand. This is the a slit in the roof and rotational capabilities, White Sands National Monument, part of and here it is, still operating today (Figure the White Sands Missile Range. Just north 7). From 1951 to 1963 this facility recorded (to the right) of the sandy area, was the flare activity. From this point onward, the White Sands Space Harbor (wssh), a back- Hilltop Dome took over the roll previously up Shuttle landing area. Other than for done by this facility. Not until 1995 was training, the wssh was only used once for a this dome to be used again. Finally a night Shuttle landing (Columbia sts-3, March 30, time observing telescope was installed. This 1982). telescope has a unique history. Sokkisha of

Figure 5. Hilltop view looking toward the White Sands National Monument. Photo by Rick Stankiewicz.

The Hilltop Dome was next in the line- Tokyo, a surveying instrument manufac- up (Figure 6). It was completed in 1963 and turer, made a few 30 cm (12”) ƒ/17.7 Casseg- originally housed several 10-20 cm (4”-8”) rains on German equatorial mounts for the telescopes. These were used to observe the U.S. military in the early 1960s, one of which Sun’s surface and atmosphere for flares and is currently in this dome and used by Sun- sunspots. It is no longer used as an observa- spot community members for observing the tory. With changes in technology and main- night sky. tenance costs in recent decades, the use of This finished our tour of the nso and this facility has gone from an observatory to though we couldn’t peer inside, it was still an instrumentation and optical design lab an interesting walk on a beautiful winter’s and was eventually closed in 2014. day and a chance to look at many pieces of Last on the tour was the Grain Bin Dome. astronomical history and all for the price of This is where it all began in 1950. While “free”. Who knows what is in store for this waiting for funding to start building the Big facility? Dome, researchers decided to start their so- lar observing with a 15 cm (6”) prominence see “Grain Bin Dome” on page 19 Vol 16 • Issue no. 4 • April 2017 • 15 The Reflector Life on Mars Calls For Some Major Lifestyle Changes

The first step in terra-forming Mars would be melting its core and getting it spinning to create an electromag- netic field. That would keep its atmosphere from being blown away by the solar wind. Once that was done you could begin the century-long second-stage of creating an Earth-like atmosphere. All things considered it looks to me like Martian spacesuits will be in style for a long time. Image from The Martian.

John Crossen he closest we Earthlings can radiation. Again you’d need a spacesuit to come to living in a Martian colony afford you some minimal protection from would be a huge apartment complex that, but what about micro-meteorites? Tthat is literally a self-contained community. On Earth micro-meteors quickly burn Restaurants, groceries, pharmacies, night- up from friction as they streak through our clubs – everything humans need or want is thicker atmosphere. Hence the percent- located in a central area. age of incoming micro-meteorites barely On Mars that might even stretch out exceeds the combined IQ of a reality show to include hospitals, emergency services, audience. But on Mars there’s not much to offices and manufacturing facilities. Ev- stop a micro-meteor. So it could punch a erything you can imagine would be a quick micro hole through your spacesuit or even elevator ride away. Or maybe you’d just step you. Ouch! onto a moving walkway. Your entire life Of course, we could terra-form Mars’ cur- could be spent under one roof. At first blush rent atmosphere to something a lot more that might sound great. But we have be- human-friendly. The best estimate we can come used to changes of scenery. Just being currently concoct for the completion of housebound for a week can be stressful. such a project is about 100 years. But there’s On Mars you don’t just step outside. That a far greater problem we’d have to address would be deadly without a spacesuit. The first. oxygen content of the Martian atmosphere Here on Earth, our planet’s molten core is only 0.13 percent, compared with 21 per- spins and generates an electromagnetic cent in Earth’s atmosphere. And it’s cold. field. It’s the reason your compass points to Living on the Martian equator the tempera- the North Magnetic Pole. But most impor- ture can reach +20C. But at night that balmy tantly Earth’s electromagnetic field helps weather can drop to -73C thanks to the fact hold on to our atmosphere. that Mars’ atmosphere is so thin that it can’t To the best of our knowledge Mars has no hold the daytime temperature in. molten core to spin and generate a magnet- Then there’s another problem associated ic field. So if terra-forming Mars is tough, with the thin Martian atmosphere – solar try kick starting its solid core. 16 • peterboroughastronomy.com continued from page 3 Three Step Solution

Nevertheless, these blue-white leds versity of Sherbrooke in Québec, Canada. turned out to be worse for light pollution Blue light also obscures people’s view of the than the orange high-pressure sodium night sky more than reddish lights. lights they replaced. Blue light at night can The American Medical Association pub- disrupt people’s sleep cycles by suppressing lished a report last June — which was en- melatonin, a hormone that normally helps dorsed by the astronomers’ resolution — ar- people sleep, more than other colors of guing that white led lights have five times light, said Martin Aubé, a physicist at Uni- continued on next page Vol 16 • Issue no. 4 • April 2017 • 17 The Reflector continued from previous page greater impact on circadian sleep rhythms The third recommendation — shield- than conventional street lamps. The LEDs ing light fixtures — matters especially for are associated with reduced sleep times, astronomy and fans of the starry sky. Many dissatisfaction with sleep quality, excessive street lamps project light upwards, but they sleepiness, impaired daytime functioning can be shielded to prevent light from being and obesity, according to recent studies. In emitted above the horizontal plane of the addition, the white leds contribute extra fixture. Lights with narrower angles further glare, putting drivers at risk. restrict the light glow above the city. But Over the past year, so called low-temper- all outdoor lamps suffer from the problem ature LEDs, which shine light with softer, of reflecting some light off the ground into yellower or redder colors, have been pro- the sky. Cities’ pavements and buildings duced with the same energy efficiency and are much shinier than the Moon’s surface, for similar prices as the bluer, less night- Lowenthal said. sky-friendly lights, said John Barentine, To get their night sky fix, many city program manager at International Dark- dwellers escape to national parks. But even sky Association in Tucson, Arizona. The natural sites are not immune from light pol- color temperature of an led, given in de- lution. A survey of visitors at Bryce Canyon grees Kelvin, describes whether the light it National Park and Cedar Breaks National emits is more red or more blue. The higher Monument, both in Utah, found that 99 per- the temperature, the bluer the light. Day- cent of them prefer to stargaze at a national light-mimicking lights are above 4,500K, park over other locations, 90 percent believe while 2,000K lights have a cozy, orange tint that there should be places that protect dark similar to the old sodium lamps. skies, and 80 percent thought that the sur- Some cities and municipalities have been rounding communities should support such using this technological advance to reduce protections, said Ashley Pipkin, a biologist their light pollution. Flagstaff and Tucson, at the National Park Service in Boulder City, Arizona have long had light pollution ordi- Nevada. nances, while Phoenix, the populous state She believes that it’s important to main- capital, last year voted to replace all 90,000 tain the view of the night sky. “It can help lamps on streets and in parks with 2,700K us understand our place in the universe leds, which have a yellower hue than their and keep inspiring generations for years to high-temperature blue-white counter- come,” Pipkin said. parts. Montreal, Canada recently adopted a (This story is reprinted and was originally 3,000K standard, while Los Angeles, Cali- published Monday, January 30, 2017, on the fornia is now doing the same for current website Inside Science, an editorially indepen- modernizations. The city previously used dent news service published by the American higher-temperature 4,000K leds, which are Institute of Physics. For a link to the original source story: less preferred by astronomers. https://www.insidescience.org/ Most outdoor lights also can be dimmed news/astronomers-encourage-cities- by 25 percent or more without any loss of shield-outdoor-lighting ) visibility, Aubé argues. The use of high- intensity lights in some areas can create the impression of a “lighting gap” as well, which can lead nearby areas to make their own lights brighter. A typical streetlight pro- vides 50 times as much illumination as the full moon, but some lights are even more intense. 18 • peterboroughastronomy.com

The Sky this Month

Mercury is at greatest elongation east (19°) on the 1st and appears as an evening star for a few days after. Ap- proaches inferior conjunction on the 20th and re-emerges as morning star at the end of the month. Venus emerges into the morning sky after inferior conjunction in March. Reaches its second stationary point on the 13th in Pisces and resumes prograde motion thereafter The Moon passes 5° south on the 23rd and reaches greatest illuminated extent 40° west of the Sun on the 30th. Mars is in Aries at the beginning of the month and moves into Taurus on the 12th. It passes within 4° of the Pleia- des near the end of the month. Jupiter at opposition on the 7th at mag. -2.5. The full Moon passes 2° north on the 10th. Saturn reaches its first stationary point on the 6th and begins retrograde motion thereafter. Remains in Sagittar- ious for the month. The waning gibbous Moon is close by on the 16th and 17th. Lyrid Meteors peak at 8 AM on the 22nd.

Moon Phases First Quarter 2:39 PM April 3 Full Moon 2:08 AM April 11 Last Quarter 5:57 AM April 19 New Moon 8:16 AM April 26 Vol 16 • Issue no. 4 • April 2017 • 19 The Reflector continued from page 12 continued from page 14 Little Facts Grain Bin Dome year, making it the new record holder for We heard while visiting the nso, that it new solar power installations in the U.S. may have had its day in the Sun, as the New Ever felt like the days were getting lon- Mexico State University maybe taking over ger — especially one when the relatives un- the facility in the near future. This should expectedly drop in for a free-load and some not be a surprise, as nso is currently invest- endless chatter? You’d be correct, though ing more on the summit of Haleakala, on not by quite as much as it feels like. Scien- Maui, Hawaii. Construction has started tists have established that the slowing of there on the world’s largest solar telescope. the Earth’s rotation will add 2 milliseconds The 4 m, Daniel K. Inouye Solar Telescope every 100 years. (dkist) will use adaptive optics to hopefully Oh, for the days when the dinosaurs provide the sharpest images of the Sun to roamed the Earth and the days were only date. The construction is due to be com- 23 hours long. Just after the Earth formed pleted by 2018. it was spinning so quickly that a day was only about three hours long. Then we got smacked by a rogue planet we have since named Thea. That smack created our Moon and its gravitational tug has slowed Earth’s rotation ever since. continued from page 13 Exoplanets all your neighbouring planets as objects Figure 7. The Grain Bin Dome. Photo by Rick Stankie- about a large as the Full Moon in our night wicz. sky. That would be breathtaking to say the least. On the un-cool side would be that all the planets are probably tidally locked to the red dwarf star. That’s because they are so close to the red dwarf that its gravitational pull has caused them to stop rotating. That could make it more difficult for life to evolve. 20 • peterboroughastronomy.com continued from page 1 TRAPPIST-1 On any of the middle planets, the light Articles side would offer a dramatic view of the Submissions for The Reflector must be received inner planets as crescents, appearing even by the date listed below. E-mail submissions bigger than the moon on closest approach. are preferred (Microsoft Word, OpenDoc, ASCII The planets only take a few days to orbit and most common graphic formats are accept- TRAPPIST-1, so from most planets, you can able). If your article contains photso or graphics, please provide a separate file for each. Typed or enjoy eclipses multiple times a week (they’d hand-written submissions are acceptable pro- be more like transits, though, since they vided they are legible (and not too long.) Copy- wouldn’t cover the whole star). righted materials will not be published without Looking away from the star on the dark written permission from the copyright holder. side, you would see the outer-most planets Submissions may be edited for grammar, brev- ity, or clarity. Submissions will be published at in their full illuminated glory. They would the editor’s sole discretion. Depending on the be so close — only a few times the Earth- volume of submissions, some articles may be moon distance — that you could see conti- published at a later date. Please submit any ar- nents, clouds, and other surface features. ticles, thoughts, or ideas to: The constellations in the background [email protected] would appear as if someone had bumped Next submission deadline: into them, jostling the stars — a perspec- April 26, 2017 tive skewed by the 40-light-years between TRAPPIST-1 and Earth. Orion’s belt is no longer aligned. One of his shoulders is lowered. And, with the help of binoculars, you might even spot the Sun as an inconspicu- ous yellow star: far, faint, but familiar. Want to teach kids about exoplanets? Go to the NASA Space Place and see our video called, “Searching for other planets like ours”: https://spaceplace.nasa.gov/exoplan- et-snap/ This article is provided by NASA Space Place. With articles, activities, crafts, games, and lesson plans, NASA Space Place encourages everyone to get excited about science and technology. Visit spaceplace.nasa.gov to explore space and Earth science!

Meetings The Peterborough Astronomical Association meets every first Friday of each month, except July and August, at the Peter- borough Zoo Guest Services and Rotary Educa- tion Centre (inside the main entrance at the north end of the Zoo) at 7 p.m. P.A.A. general annoucements will begin each meeting with the guest speaker starting at 7:30 p.m.