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[TomT]

download the attached audio file to play the show (ads removed) ~47:30 length; let me know if it plays well for you.  I amplified this version as it seemed the show was a bit low in recorded volume.

JerryW's agenda for the show:
On 11/7/2020 9:49 PM, Jerry wrote:
> Comet Alert
>    Comet C/2020 M3 (ATLAS) glides between Orion the Hunter’s three-star belt and his left knee, magnitude 0.2 Rigel, tonight. After dark, step outside to find the comet just 1° south-southwest of magnitude 3.4 Eta (η) Orionis. According to the Comet Observation database, ATLAS is roughly magnitude 8 — viewable with binoculars or a small telescope. Its coma stretches about 8' across. For the best visibility, consider staying out overnight and watching it into the early morning hours this week.
>    This comet is moving quickly through Orion from night to night, and it’s headed north for a rendezvous with Bellatrix next week. ATLAS has already made its closest approach to the Sun (October 25) and will make its closest approach to Earth on the 14th, when it comes within 0.4 astronomical units of our planet. (One astronomical unit is the average Earth-Sun distance.)
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Monday, November 9
>    At the feet of the well-known constellation Orion sits Lepus the Hare. Formed by roughly a dozen stars, this dim figure fully clears the horizon just before 10 P.M. local time and is visible even from suburban locations. Some stories depict Lepus as being hunted by the Hunter or his dogs, Canis Major and Canis Minor — and you’ll see the two hounds clearing the horizon shortly after. But alternate tales claim Lepus crouches at Orion’s feet for protection from other hunters that might consider him prey.
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>    The constellation’s brightest (alpha) star, magnitude 2.6 Arneb, is about 9° southwest of Orion’s right knee, Saiph. (His left knee, Rigel, is much brighter.) But through binoculars, magnitude 3.6 Gamma (γ) Leporis might be the most distinct of Lepus’ stars, with a companion star glowing at magnitude 6 just 97" to the north. The two are slightly different colors, with brighter Gamma A appearing yellower than dimmer Gamma B, which looks more orange.
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>    Nearby is M79, a globular cluster that sits a little less than 4° south of Nihal (Beta [β] Leporis). One of the few good winter-sky globulars, this densely packed group of some 100,000 stars may once have been part of the Canis Major Dwarf Galaxy — the closest galaxy to the Milky Way that astronomers have found to date.
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> Tuesday, November 10
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>    Mercury reaches greatest western elongation (19°) from the Sun at noon EST today. The planet is an early morning object, rising about an hour and a half before the Sun. Today, it’s glowing at magnitude –0.5 and is roughly 13° high by 6:15 A.M. local time. Above it, the bright planet Venus is 25° high. With optical aid, you’ll see that Mercury is nearly 60 percent lit and spans 7". Venus, which stretches 13" across, is 84% lit.
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>    We’ll check back in with these planets later in the week, when the crescent Moon joins them. Our satellite isn’t hard to find, though — it’s northwest of the planets, higher in the sky as it floats near the hindquarters of Leo the Lion. The Moon is positioned this morning on a line drawn between Iota (ι) and Rho (ρ) Leonis, both magnitude 4, and sits south-southwest of the magnitude 3 star Chertan.
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> Wednesday, November 11
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>    Even as the Leonid meteor shower is ramping up for a treat later this month, the lesser-known Northern Taurid meteor shower peaks overnight tonight and into tomorrow morning. These meteors are debris left by Comet 2P/Encke; they zip through our atmosphere at about 18 miles (29 km) per second. Observers can expect to spot roughly five to 10 meteors per hour during the shower’s peak. Admittedly, that’s not much more than the average background rate of meteors (seven per hour) this time of year, but bright fireballs are more likely during showers.
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>    The best time to look for shower meteors is late tonight and early tomorrow morning, when Taurus is high in the sky. You’ll find the radiant about 2.5° southeast of the familiar Pleiades (M45). Even if the Northern Taurids put on a poor show, this beautiful open cluster is a rich region to explore with binoculars or any size scope. With the Moon a mere 15 percent lit, it’s also a great night to see if you can spot any nebulosity between the cluster’s brightest stars. This dim, wispy glow comes from gas and dust that reflects, rather than absorbs, the nearby starlight.
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> Thursday, November 12
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>    The Moon passes 3° north of Venus at 1 P.M. PST. A little more than two hours before dawn, eager skywatchers will find them rising in the east, just over 6° apart. Venus is blazingly bright at magnitude –4 and sits very close to magnitude 4.4 Theta (θ) Virginis in Virgo the Maiden. The two are less than 0.5° apart.
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>    Before the sky grows too light, look North of Virgo for the Big and Little Dippers — both asterisms within the larger Ursa Major and Ursa Minor constellations, respectively. This morning, the Little Dipper appears upright, which means the Big Dipper appears nearly upside-down. As you look north, you’ll see the Big Dipper to the upper right of its littler counterpart. Directly beneath the Little Dipper is the twisting form of Draco the Dragon, whose alpha star Thuban (located about 10° south of the right-hand edge of the Little Dipper’s cup) once sat above Earth’s north pole as its pole star.
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> Friday, November 13
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>    The Moon passes 1.7° north of Mercury at 1 P.M. PST. Catch the pair in the hour or so before sunrise this morning in Virgo, where they’re rising in the east, preceding our star. At that time, the delicate crescent Moon stands 5° above Mercury, which glows an easy magnitude –0.7, only slightly dimmer than it appeared just days ago. Mercury now sits just 2° west of magnitude 4 Kappa (κ) Virginis.
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>    Nearby is blazingly bright Venus, now about 1.5° southeast of Theta Virginis. Glance down a bit and you won’t be able to miss Spica, Virgo’s brightest star (magnitude 1). You should be able to follow the scene well into morning twilight.
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> Mysteries Beyond Neptune.
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>    Astronomers have discovered 139 new minor planets orbiting the Sun beyond Neptune by searching through data from the Dark Energy Survey. The new method for spotting small worlds is expected to reveal many thousands of distant objects in coming years — meaning these first hundred or so are likely just the tip of the iceberg.
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>    Taken together, the newfound distant objects, as well as those to come, could resolve one of the most fascinating questions of modern astronomy: Is there a massive and mysterious world called Planet Nine lurking in the outskirts of our solar system?
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>    Neptune orbits the Sun at a distance of about 30 astronomical units (AU; where 1 AU is the Earth-Sun distance). Beyond Neptune lies the Kuiper Belt — a comet-rich band of frozen, rocky objects (including Pluto) that holds dozens to hundreds of times more mass than the asteroid belt. Both within the Kuiper Belt and past its outer edge at 50 AU orbit distant bodies called trans-Neptunian objects (TNOs). Currently, we know of nearly 3,000 TNOs in the solar system, but estimates put the total number closer to 100,000.
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>    As more and more TNOs have been discovered over the years, some astronomers — including Konstantin Batygin and Mike Brown of Caltech — have noticed a small subset of these objects have peculiar orbits. They seem to bunch up in unexpected ways, as if an unseen object is herding these so-called extreme TNOs (eTNOs) into specific orbits. Batygin and Brown — in addition to other groups, like that led by Scott Sheppard of the Carnegie Institution for Science — think these bizarrely orbiting eTNOs point to the existence of a massive, distant world called Planet Nine.
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>    Hypothesized to be five to 15 times the mass of Earth and to orbit some 400 AU (or farther) from the Sun, the proposed Planet Nine would have enough of a gravitational pull that it could orchestrate the orbits of the eTNOs, causing them to cluster together as they make their closest approaches to the Sun.
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>    The problem is that the evidence for Planet Nine is so far indirect and sparse. There could be something else that explains the clumped orbits, or perhaps researchers stumbled on a few objects that just happen to have similar orbits. Discovering more TNOs, particularly beyond the Kuiper Belt, will allow astronomers to find more clues that could point to the location of the proposed Planet Nine — or deny its existence altogether. Of the 139 newly discovered minor planets found in this study, seven are eTNOs, which is a significant addition to a list that numbered around a dozen just a few months ago.
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>    The new TNOs were found by astronomers at the University of Pennsylvania using data from the Dark Energy Survey (DES), which was not originally designed to look for distant minor planets.
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>    Unfortunately, the new objects don’t yet lead to anything conclusive about Planet Nine. The researchers released early results analyzing whether the orbits of the seven newfound eTNOs support the clustering pattern that points to Planet Nine, but so far, they’ve turned up nothing.
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>    “If this were the first dataset that came out, then no one would have come up with the Planet Nine hypothesis because there appears to be no clustering [in the orbits of the new eTNOs],” says Sako. However, he adds that this doesn’t disprove the existence of Planet Nine either. Their method could uncover other eTNOs that do support the proposed Planet Nine — or even spot the object itself.
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> Snoopy, Where are you?
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>    All but one of the Apollo program’s used lunar modules either crashed into the Moon’s surface or burned up in Earth’s atmosphere. Apollo 10’s lunar module, Snoopy, is still out there, drifting aimlessly around the solar system, waiting for some future exo-archaeologist to snatch it up for display at the Smithsonian.
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>    The mission was designed as a rehearsal for the main event on the Moon, but it set records of its own. History glazes over Apollo 10 because of the significance of what followed; however, the crew completed the same tasks as Apollo 11 (minus landing on the Moon).
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>    And they used Snoopy, the lunar module, as well as Charlie Brown, the command module, to travel farther and faster than any humans have before or since.
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>    During the mission, Snoopy was jettisoned into space as planned and would have entered orbit around the Sun. However, its location remains a mystery despite efforts by amateur astronomers to search for it using the last known 1969 orbital coordinates. They identified a number of target sites, but so far they’ve been unsuccessful.
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>    Interestingly, many of the other landers’ exact lunar impact sites — including Apollo 11’s Eagle — are also a mystery that future space explorers may someday find and excavate, like underwater archaeologists uncovering Amelia Earhart’s Lockheed Electra.
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> Seeding Life on Earth?
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>    A meteorite that landed on a frozen lake in 2018 contains thousands of organic compounds that formed billions of years ago and could hold clues about the origins of life on Earth.
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>    The meteor entered Earth's atmosphere on Jan. 16, 2018, after a very long journey through the freezing vacuum of space, lighting up skies over Ontario, Canada, and the midwestern United States. Weather radar tracked the flaming space rock's descent and breakup, helping meteorite hunters to quickly locate fallen fragments on Strawberry Lake in Hamburg, Michigan.
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>    The meteorite held 2,600 organic, or carbon-containing compounds, the researchers reported in the study. Because the meteorite was mostly unchanged since 4.5 billion years ago, these compounds likely are similar to the ones that other meteorites brought to a young Earth, some of which "might have been incorporated into life," Heck said.
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>    The transformation from extraterrestrial organic compounds into the first microbial life on Earth is "a big step" that is still shrouded in mystery, but evidence suggests that organics are common in meteorites — even in thermally metamorphosed meteorites such as the one that landed in Michigan, he added. Meteor bombardment was also more frequent for a young Earth than it is today, "so we are pretty certain that the input from meteorites into the organic inventory on Earth was important," for seeding life.
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> Sent from my iPad