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China Lake Astronomical Society Members and Friends of CLAS Volume 58 No. 1 January 01, 2021 January 4 CLAS Meeting – Members’ Astrophotography Showcase 2020 Have you taken any pictures of the night sky this year? Please share them with CLAS members at the January online Zoom meeting, and give us a brief explanation of the subjects and how you photographed them. Show us your favorite shots, and even the ones you tried that didn’t quite work out. Send us your photos (and videos) via email and we’ll add them to the program, and you can talk about them if you wish when yours are shown We’ll also share them on our website. Guidelines 1. Email photos to Ralph Paonessa: [email protected] by Sunday, January 3. 2. Ideal size is around 1920 x 1080 pixels (full screen), but we can resize them if necessary. 3. Include a brief description with each photo including a. Subject and where it was taken b. Equipment and any details about how you shot it c. Your name We look forward to seeing your astrophotography! Zoom Meeting China Lake Astronomical Society is inviting you to a scheduled Zoom meeting. Topic: AS Meeting Time: January 04, 2021 07:30 PM Pacific Time (US and Canada) Join Zoom Meeting https://us02web.zoom.us/j/6727499334?pwd=VWhuVGZ3aFphL283THRKNUNoZ0RSZz09 Meeting ID: 672 749 9334 Passcode: 9V8FQM One tap mobile +14086380968,,6727499334#,,,,,,0#,,562029# US (San Jose) +16699006833,,6727499334#,,,,,,0#,,562029# US (San Jose) Dial by your location +1 408 638 0968 US (San Jose) +1 669 900 6833 US (San Jose) +1 253 215 8782 US (Tacoma) +1 346 248 7799 US (Houston) +1 301 715 8592 US (Germantown) +1 312 626 6799 US (Chicago) +1 646 876 9923 US (New York) Meeting ID: 672 749 9334 Passcode: 562029 Find your local number: https://us02web.zoom.us/u/keA8HEm1mp President’s Message While 2020 is a year we’d mostly like to forget, it at least has some notable memories for astronomers. My favorite was the appearance of magnificent Comet NEOWISE in July. This was the best comet in the Northern Hemisphere since Hale-Bopp in 1996-97. This year, twenty-three years later, newly-discovered C/2020 F3 (NEOWISE) finally arrived with its long tail I could see my naked eyes from a dark sky—and spectacular in binoculars or a camera. I’m still hoping for the appearance of a true “Great Comet,” one that is easily visible to the naked eye—maybe even during the day! But I’m very satisfied with NEOWISE. The planets also put on a good display this year. On July 14, Jupiter was at opposition—directly opposite the Sun and thus high overhead at midnight. And nearest its closest to Earth, and so at its brightest and largest in our telescopes. One week later, it was Saturn’s turn at opposition on July 20, making this lovely ringed world bright and large in our scopes. Throughout the summer, they remained high and bright in the sky, perfect for observing. Not to be outdone, the red globe of Mars spend most of 2020 brightening until it reached opposition October 13, high in the winter sky where good views could be had in telescopes. (This year was the first time I could clearly see details on the Martian surface in a large telescope, a surprise that left me a little awe-struck.) Fearing that their glory might be eclipsed by Mars, Jupiter and Saturn picked up the pace and sped to their historic Great Conjunction on December 21—the closest they’ve been visible in the sky in 794 years!! That was in the year 1226. (They were close in 1623, but then they were also close to the sun and so almost impossible for anyone to see.) Sadly, we weren’t able to hold our planned viewing event because of the spike in coronavirus cases, but all you had to do was walk outside shortly after sunset and there they were, as close together as one-sixth the diameter of the Full Moon. A great way to celebrate the Winter Solstice and the longest night of the year, even if you had to do it alone. (But we’re planning another event for 2080, when they’ll be close again!) This year has been one for the record books, and mostly in bad ways! But I hope you were at least able to get occasional comfort from going out at night and gazing at the heavens and all their wonders, from here on our little rock. Here’s hoping to a Happier and healthier New Year for all! — Ralph Paonessa, President Next CLAS Meeting: February 1st, 2021 at 7:30 PM. Citizen astronomers map near-Earth asteroid Professional and backyard astronomers have teamed up to measure the shape of an asteroid using a unique new instrument. By Mark Zastrow | Published: Tuesday, December 29, 2020 The Unistellar eVscope is pictured here at Meteor Crater in this press kit photo. SETI Institute, Unistellar In the battle to defend the planet from hazardous asteroids, amateur astronomers have taken on a new role — for the first time, helping to map a near-Earth asteroid (NEA), revealing its shape.The effort came as a collaboration between researchers at the SETI Institute and 26 citizen observers from seven countries who observed the 1.2-mile- wide (2 kilometers) asteroid 1999 AP10. All of the observers were using an eVscope — a new “smart” telescope model produced by the startup Unistellar. Amateur astronomers have always been on the front lines of planetary defense as discoverers of asteroids and comets. Their observations and submissions to organizations like the Minor Planet Center are invaluable in tracking objects that could one day collide with Earth.But this is the first time that amateur observers have teamed with researchers to generate a detailed model of the shape of an asteroid. They used a technique called light curve inversion, which analyzes how an object changes brightness as it tumbles and rotates through space, reflecting sunlight differently at every angle. Using the 81 sets of observations that eVscope users collected over October and November — plus some archival data from 2009 — the researchers were able to reverse engineer the asteroid’s physical shape.Previously, astronomers had determined the shapes of only 68 other near-Earth asteroids, mostly using powerful planetary radar facilities to do so.The team presented their results on December 9 at the 2020 fall meeting of the American Geophysical Union, held online.The results are also a milestone for the eVscope, which began as a Kickstarter campaign in 2017. The initial campaign was so successful it spawned the company Unistellar, which has now shipped about 3,000 eVscopes to users.The eVscope’s main claim to fame is that instead of an optical eyepiece, it has a built-in CMOS sensor and can stack images on the fly. Users can view the results on a paired smartphone or peer into the telescope’s electronic “eyepiece,” which projects an image from an OLED screen, similar to electronic viewfinders commonly found on mirrorless cameras.Another key feature is that users can participate in observing campaigns developed through a partnership between Unistellar and scientists from the SETI Institute. The observations from citizen astronomers resulted in this model of the near-Earth asteroid 1999 AP10. Credit: Josef Hanuš, Charles University & Franck Marchis, SETI Institute Franck Marchis of the SETI Institute tells Astronomy that the ability to tap into a network of thousands of identical eVscopes is a “game-changer” because results from standardized equipment can be combined more consistently. “You know that the telescopes react with the same sensitivity, the same quantum efficiency, the same profile of different colors,” he says. “That means we can clearly identify if there is an issue coming from the seeing, from the sky quality, or from the wind.”Plus, instead of relying only on advanced amateurs who know how to calibrate their equipment and process their data, the science team can program the eVscope to do it automatically, allowing anyone to participate.Marchis hopes to compare their model of 1999 AP10 with forthcoming results from the Goldstone Solar System Radar, which also observed the asteroid this fall. But already the campaign has demonstrated the eVscope’s potential for including amateur astronomers in scientific research, he says.Other researchers agree. “I think this is a great public engagement project that can provide useful and helpful data for asteroid research, including planetary defense,” says Anne Virkki, who heads the planetary radar team at Arecibo Observatory.Arecibo’s 1,000-foot-wide (305 meters) radio telescope was the world’s most powerful planetary radar before it collapsed following a series of cable failures this fall. Its loss was a big blow to planetary defense efforts — NASA funded the observatory to observe near-Earth objects, mapping their shapes and surfaces.Although comparing the eVscope to a planetary radar like Arecibo is “a bit of an apples-and oranges comparison,” says Virkki, “more data is always a plus, and having the public engaged in participating and helping is even a bigger plus.”The crowdsourced light curve approach does have limitations. Unlike planetary radars such as Arecibo, the eVscope network struggles to detect depressions on an asteroid’s surface (e.g., impact craters). That’s because the math behind the light curve inversion approach assumes the object is entirely convex, with no low-lying regions.Arecibo could also observe more objects, obtaining high-resolution images of 20 to 30 NEAs per year, according to Virkki. Marchis hopes that the eVscope network will map one or two NEAs annually.
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  • 1 the Solar Neighborhood III: a Near Infrared Search for Widely Separated Low Mass Binaries
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