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On 10/10/2020 9:23 PM, Jerry wrote these notes to guide our conversations:
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> Monday, October 12The constellation Cetus the Whale is rising in the southeast as darkness falls. You can track it over the next few hours, as its stars climb higher in the sky. Focus in on one star in particular: the variable star Mira, whose very name means “wonderful.”
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>    You can find Mira, also cataloged as Omicron (ο) Ceti, roughly in the center of the constellation, about one-third of the way on a line drawn southwest from Menkar (magnitude 2.5) toward Diphda (magnitude 2). Mira is a long-period variable, swinging from 2nd to 10th magnitude and back over the course of 332 days. That means its brightness changes by a factor of 1,600 between its brightest and its dimmest.
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>    Consider visiting this variable once every one to two weeks this fall and winter to see if you can note its change over time in comparison to other, nearby stars. You can check out Phil Harrington’s column in Astronomy’s October 2020 issue for more details on this wonderful little star and step-by-step instructions on how to track its brightness in the coming months.
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> Tuesday, October 13
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>    The big night is finally here: Mars reaches opposition at 7 P.M. EDT, just one week after its closest approach to Earth. It’s blazing at magnitude –2.6 in the southeast, amid the stars of Pisces and about 10° high in the east an hour after sunset. It will climb higher as the hours tick by; the best time to observe the Red Planet is late this evening in the hours leading up to local midnight, when it is high above the horizon. It’s in a relatively dark part of the sky and in a faint constellation, so it will be easy to pick out, thanks to its brightness and its distinctive red color.
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>    Mars’ disk appears 22.4" across tonight, just 0.2" smaller than at its closest approach last week. At 11 P.M. EDT, the dark swath of Mare Cimmerium is visible, with Syrtis Minor rotating onto the disk. Follow the planet for a few more hours overnight, and you’ll see the bright Hellas basin appear. Also prominent will be the dark Syrtis Major region. Although astronomers once thought observed seasonal changes in this distinctive feature might be due to martian vegetation, today we know that its fluctuating appearance is actually due to sand blowing across the planet’s desolate surface.
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>    The Moon passes 4° north of Venus at 8 P.M. EDT, although both are still below the horizon. We’ll come back to them in just a few hours.
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>    Mercury is stationary at midnight EDT. It’s well below the horizon by then, but you can view it tomorrow at sunset.
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> Wednesday, October 14
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>    Today holds amazing solar system sights for both morning and evening observers. For those up before the Sun, you can spot the delicate crescent Moon — with just eight percent of its surface lit — join the planet Venus in the morning sky. Look east in the two hours before sunrise to glimpse the pair in the southern portion of Leo the Lion, about 9° southwest of Denebola (which you may remember from earlier this week marks the tip of Leo’s tail). See if you can spot any earthshine on the lunar surface, which occurs when sunlight bounces off Earth and lights up the portion of the Moon in Earth’s shadow.
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>    Lucky — and speedy — evening observers can catch magnitude 0.9 Mercury low in the western sky at sunset tonight. It’s only 5° high as the Sun sinks below the horizon and is completely gone within about 30 minutes.
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>    As Mercury disappears, look to its north. Higher above the horizon, you’ll see the bright star Arcturus in Boötes pop out in the darkening twilight. This red giant shines 113 times more brightly than our Sun and weighs about one-and-a-half times as much as our star.
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> Thursday, October 15
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>    Jupiter and Saturn set before local midnight in the south, still embedded within the stars of Sagittarius. You can find the giant planets to the northeast (upper left) of the Teapot asterism. The two planets are currently just under 6.5° apart, with magnitude 0.5 Saturn east of magnitude –2.3 Jupiter.
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>    Tonight, focus in on Jupiter with binoculars or a telescope after dark to see all four of its largest moons off to the planet’s east. But not for long — just after 9:40 P.M. EDT, the closest moon, Io, slips onto the disk. About 80 minutes later, its shadow follows, as Io is already more than halfway across Jupiter’s face. Jupiter is still about 4° above the horizon for observers at 40° north latitude when Io leaves the planet’s western limb just before midnight EDT. Observers on the East Coast and in the Midwest won’t get to see Io’s shadow disappear (around 1:13 A.M. EDT) before the planet sets, but West Coast observers will be able to catch the show’s finale.
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> Friday, October 16
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>    New Moon occurs at 3:31 P.M. EDT. The Moon is also at perigee today, the closest point in its orbit to Earth. It currently sits 221,775 miles (356,912 kilometers) away.
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> Unauthorized access.
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>    New Moon is the best time to seek out dim objects — and constellations — washed out by our satellite’s bright glare. Tonight, try to catch Delphinus the Dolphin high in the southwest after dark. This tiny constellation, which ranks 69th in size among the 88 official constellations, consists of four stars that form the dolphin’s body, as well as one additional star that marks its tail. The four stars of Delphinus’ body also create an asterism known as Job’s Coffin, which measures just 1.3° by 2.7°.
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>    Although this aquatic constellation may not look like much to the naked eye, turning binoculars or a small scope on the region can bring out a wealth of field stars to enjoy on a dark night like tonight.
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> SBAU Workshop back on
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>    It’s been a gloomy year for amateur astronomy, including the SBAU. Our face to face public outreach events remain on hold until at least the new year. But we are trying to resuscitate our Tuesday evening Telescope Workshop using Zoom and have had two meetings so far with good results. These trial meetings were hosted by Joe Doyle using  his personal zoom account. The Santa Barbara Museum of Natural History has now provided their zoom account so meetings can now be closer to the traditional 90 minute length. These meetings are focused on telescope designs, repair, use, imaging, or general astronomy questions from the general public. To participate, send an email to Jerry Wilson President of the SBAU. Email address can be found at www.SBAU.org. 
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> Last, but not least: Remember that cool video of stars orbiting the black hole at the center of the Milky Way. Well...
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>    Andrea Ghez, UCLA’s Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics, today was awarded the 2020 Nobel Prize in physics.
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>    Ghez shares half of the prize with Reinhard Genzel of UC Berkeley and the Max Planck Institute for Extraterrestrial Physics. The Nobel committee praised them for “the discovery of a supermassive compact object at the centre of our galaxy.” The other half of the prize was awarded to Roger Penrose of the University of Oxford “for the discovery that black hole formation is a robust prediction of the general theory of relativity.”
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>    In July 2019, the journal Science published a study by Ghez and her research group that is the most comprehensive test of Albert Einstein’s iconic general theory of relativity near the monstrous black hole at the center of our galaxy. Although she concluded that “Einstein’s right, at least for now,” the research group is continuing to test Einstein’s theory, which she says cannot fully explain gravity inside a black hole.
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> Ghez studies more than 3,000 stars that orbit the supermassive black hole. Black holes have such high density that nothing can escape their gravitational pull, not even light. The center of the vast majority of galaxies appears to have a supermassive black hole, she said.
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>    “I’m thrilled and incredibly honored to receive a Nobel Prize in physics,” said Ghez, who is director of the UCLA Galactic Center Group. “The research the Nobel committee is honoring today is the product of a wonderful collaboration among the scientists in the UCLA Galactic Center Orbits Initiative and the University of California’s wise investment in the W.M. Keck Observatory.
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>    “We have cutting-edge tools and a world-class research team, and that combination makes discovery tremendous fun. Our understanding of how the universe works is still so incomplete. The Nobel Prize is fabulous, but we still have a lot to learn.”
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> Sent from my iPad