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

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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).
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