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[TomT]

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Also, a transcript of the program was made by MS Word online transcribe function...20 pages of approximate conversation that will need some careful consideration of what is being said and by whom...is attached as well.

 Topics that were to be considered:

On 8/22/2020 10:42 PM, Jerry wrote:
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> Monday, August 24
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>    Pegasus the Winged Horse is rising in the east after sunset, climbing higher in the sky as evening proceeds. This large constellation is home to the globular cluster M15 (NGC 7078), sometimes called the Great Pegasus Cluster. M15 is located just over 4° northwest of magnitude 2.4 Enif, the brightest star in Pegasus despite its designation of Epsilon (ε) Pegasi. You’ll find Enif west of the Great Square of Pegasus, roughly 20° west of Markab. Enif, which means “the nose” in Arabic, is typically drawn as the flying horse’s mouth or muzzle.
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>    M15 itself is magnitude 6 and spans 12.3'. It lies about 33,600 light-years away and is one of our galaxy’s oldest globular clusters. M15 will look noticeably fuzzy in binoculars, especially compared to the 6th-magnitude star located just to its west.
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>    This dense globular cluster is also the first globular discovered to contain a planetary nebula, which is the shell of gas blown out by a dying star and subsequently lit up by that star as it fades. The nebula, Pease 1, is challenging to spot even with a large (15 inches or greater) telescope and requires dark skies and patience to pick out from the busy background of the packed cluster. If you’re an experienced observer or photographer looking for a challenge, push the magnification to 300x or greater and look about 1' northeast of the cluster’s core for the tiny, bubblelike nebula.
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> Tuesday, August 25
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>    First Quarter Moon occurs at 1:58 P.M. EDT. Because it rises at essentially the same time, our satellite is visible all evening, already in the sky at sunset and sinking below the horizon just shy of midnight. It’s a great time to settle back for some easy lunar observing. The terminator, which divides night from day, is moving relatively fast; between sunset and moonset, you may be able to detect its motion if you come back to the Moon several times.
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>    Several of the Moon’s large seas are on display for Northern Hemisphere observers: Frigoris, Serenitatis, Tranquillitatis, Nectaris, Crisium, and Fecunditatis. The large crater at Fecunditatis’ eastern edge is Langrenus. From directly above, the 81-mile-wide (130 km) crater is a near-perfect circle; but from our perspective here on Earth, it appears more as an oblong shape, thanks to the curvature of the lunar surface.
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> Wednesday, August 26
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>    Already high overhead at sunset, Cygnus the Swan is your target tonight. Lurking within this graceful grouping of stars is the sky’s surest black hole, one of two components of the binary system called Cygnus X-1. Although the black hole itself is invisible, its companion star — a hot, blue-white giant with the inauspicious designation HDE 226868 — is not. HDE 226868 (also designated HIP 98298, among a few other names) is an 8th-magnitude star less than 0.5° east of Eta (η) Cygni. It’s detectable with binoculars and more easily with a telescope.
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>    HDE 226868 orbits its black hole companion every 5.6 days, flung around by the compact massive object’s immense gravity. Astronomers suspect the pair is so close that the black hole is actively feeding on HDE 226868 as well, pulling material off the star and onto a disk of material that ultimately swirls into the black hole like water flowing down a drain.
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> Thursday, August 27
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>    With a brilliant opposition coming up October 13, we’re now in peak Mars observing season. The best time to observe it is a few hours before sunrise, when the Red Planet is high above the southern horizon, shining at magnitude –1.7 in southeastern Pisces. Its disk is currently 90 percent lit and spans 18". By the end of the month, it will span 19" and grow to 92 percent lit.
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>    Summertime is approaching in the Red Planet’s southern hemisphere; if you observe the planet with a telescope, you’ll see that its southern polar cap, tilted toward Earth, is relatively small. Because of its brilliance, the bright Hellas basin is often confused for the polar cap. The large basin is visible around 1 A.M. EDT and rotates off the disk within about three hours. Come back tomorrow night at the same time for a bit more time to search it out — thanks to the Red Planet’s rotation rate of 24 hours 37 minutes, Mars’ features appear to move slightly backward when viewed at the same time on successive nights.
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> Thursday, August 28
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>    Dwarf Planet 1 Ceres reaches opposition at 8 A.M. EDT. It’s glowing at magnitude 7.7 — within reach of binoculars or a small scope — and visible in Aquarius both early this morning and late this evening. The tiny world is currently 186 million miles (299 million km) from Earth. You’ll find it this morning about halfway on a line drawn between the bright stars Fomalhaut in Piscis Austrinus and Skat in Aquarius. It’s moving slowly west but is still roughly between the same stars by evening.
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>    While you’re in the area, look about 13° northeast of Skat to find Neptune. For a closer signpost, the planet is less than 3° east of 4th-magnitude Phi (φ) Aquarii. At magnitude 7.8, our solar system’s outermost planet is roughly the same brightness as Ceres.
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>    Asteroid 20 Massalia reaches opposition at 5 P.M. EDT, when it is nearly 147 million miles (236 million km) from Earth. It, too, is in Aquarius, about 14° due west of Neptune but glowing a much fainter magnitude 9.4.
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>    The Moon passes 1.4° south of Jupiter at 10 P.M. EDT. The pair, along with Saturn just 8.3° east of Jupiter, is in Sagittarius. The constellation is southwest of where you’ll find Ceres, Massalia, and Neptune in Aquarius.
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> ASTEROID SAMPLE RETURN IN DECEMBER
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>    The Hayabusa2 spacecraft is trekking back to Earth with a sample capsule full of material snagged from a near-Earth asteroid called Ryugu. The Japan Aerospace Exploration Agency (JAXA), which runs the mission, has long planned to deposit that capsule in the vast desert of Australia, but the new announcement marks that country's official approval of the plan.
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>    Over the course of its stay at Ryugu, Hayabusa2 collected samples from the asteroid's rocky surface, shot the asteroid to create an artificial crater, and collected some of the subsurface material uncovered by that impact as well. The diversity of samples means that scientists will be able to learn more about Ryugu's interior and how it has responded to the harsh forces of outer space, like the solar wind, a constant stream of highly energized particles called plasma flowing off the sun.
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>    But even with advanced spacecraft, scientists can always do more detailed analyses in laboratories on Earth, hence the need to land that capsule. Hayabusa2's predecessor, another asteroid sample-return mission called Hayabusa that visited a space rock called Itokawa, also returned its material to Australia, and the current mission will follow suit, with the deposit scheduled for Dec. 6.
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>    However, unlike Hayabusa, the current spacecraft will not return in full; it will only deposit a sample capsule back to Earth. JAXA is evaluating sending the Hayabusa2 probe on to visit a second asteroid about a decade from now.
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> COMET IN THE MAKING
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>    Like the mythical half-human, half-horse creatures, centaurs in the solar system are hybrids between asteroids and comets. Now, astronomers have caught one morphing from one type of space rock to the other, potentially giving scientists an unprecedented chance to watch a comet form in real time in the decades to come.
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>    “We have an opportunity here to see the birth of a comet as it starts to become active,” says planetary scientist Kat Volk of the University of Arizona in Tucson.
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> The object, called P/2019 LD2, was discovered by the ATLAS telescope in Hawaii in May. Its orbit suggests that it’s a centaur, a class of rocky and icy objects with unstable orbits. Because of that mixed composition and potential to move around the solar system, astronomers have long suspected that centaurs are a missing link between small icy bodies in the Kuiper Belt beyond Neptune and comets that regularly visit the inner solar system (SN: 11/19/94).
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>    These “short-period” comets, which are thought to originate from icy objects in the Kuiper Belt, orbit the sun once a decade or so, and make repeat appearances in Earth’s skies. (Long-period comets, like Halley’s Comet, which visits the inner solar system once a century, probably originate even farther from the sun, in the Oort cloud (SN: 10/25/13).)
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>    All previously found short-period comets were spotted only after they had transitioned into comets (SN: 8/6/14). But LD2 just came in from the Kuiper Belt recently and will become a comet in as little as 43 years, Volk and colleagues report August 10 at arXiv.org.
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>    “It’s weird to think that this object should be becoming a comet when I’m retiring,” Volk says.
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>    In 2019, she and colleagues showed that there’s a region of space just beyond Jupiter that they call the “Gateway”.  In this area, small planetary objects hang out while warming up and transitioning from outer solar system ice balls to inner solar system comets with their long tails. It’s like a comet incubator, says planetary scientist Gal Sarid of the SETI Institute, who is based in Rockville, Md.
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>    After hearing about LD2, Volk, Sarid and their colleagues simulated thousands of possible trajectories to see where the object had been and where it is going. LD2’s orbit probably took it near Saturn around 1850, and it entered its current orbit past Jupiter after a close encounter with the gas giant in 2017, the team found. The object will leave its present orbit and move in toward the sun in 2063, where heat from the sun will probably sublimate LD2’s volatile elements, giving it a bright cometary tail, the researchers say.
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>    “This will be the first ever comet that we know its history, because we’ve seen it before being a comet,” Sarid says.
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>    The fact that LD2 is fairly new to the inner reaches of the solar system suggests that it’s made of relatively pristine material that has been in the back of the solar system’s freezer for billions of years, unaltered by heat from the sun. That would make it a time capsule of the early solar system. Studying its composition could help planetary scientists learn what the first planets were made of.
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> DO WE LIVE IN A MULTIVERSE?
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>    For as long as humans have gazed skyward, a question has loomed in the back of our collective mind: How do we know everything that we see is everything there is?
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>    Decades of astrophysical research beginning in the late 19th century established the universe as we see it, culminating with the Big Bang theory. We now know the universe is about 13.8 billion years old and at least 150 billion trillion miles across. But in recent years, astronomers have begun to address a staggering possibility — the universe we can observe, and in which we live, may be one of many that makes up the cosmos.
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>    The suggestive evidence for this comes from several directions, from the idea of cosmic inflation, from string ttheory and the existence of the famous cosmological constant. Some of the notions that come out of these lines of evidence are pretty counterintuitive. Yet that doesn’t worry astronomers. “I fully expect the true nature of reality to be weird and counterintuitive,” says cosmologist Max Tegmark of the Massachusetts Institute of Technology, “which is why I believe these crazy things.”
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>    The idea of multiple universes, or multiverses, poses the notion of the universe existing like a giant sponge. Each bubble is a distinct universe, like ours, but others could exist separated by giant voids.
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>    What’s the evidence for all this? First, measurements of distant supernovae suggest the expansion of the cosmos is accelerating. Second, more and more evidence supports the inflationary scenario of the early history of the universe. Third, ideas about inflation suggest many Big Bangs may have occurred. Fourth, recent notions about string theory suggest universes of very different types may have formed. Altogether, these notions suggest it was possible, if not probable, that multiple universes of different types formed in the past, and they coexist with the familiar cosmos we can see.
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>    Even without other universes, astronomers know the universe is larger than what we see with our telescopes. The view horizon now spans about 14 billion light-years; and if you count the knowledge that distant objects have expanded far beyond what we now see, the “currently” existing horizon is at least 40 billion light-years across.
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>    Accepting an inflation-based universe of the size we see, Jaume Garriga of the University of Barcelona and Alexander Vilenkin of Tufts University have proposed a cosmos peppered with numerous “O-regions,” observable universes like ours. Part of the idea goes that inflation, the hyperexpansion in the early universe, never completely stopped. It stopped where we are, producing our O-region, and many others. But in other areas of the universe at large, it continues. This creates a concept called eternal inflation — a universe unlike a simple sphere, instead rather like a sponge, pocked with holes that are bubble universes.
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>    How convincing is this to astrophysicists? Tegmark remains open. “As scientists,” he says, “We’re not testing the general idea of a multiverse. We’re testing inflation — a mathematical theory that predicts a multiverse and all kinds of other stuff.” Vilenkin looks ahead to an exciting future of learning more about multiverses. “By doing measurements in our own region,” he says, “We can test our predictions for what lies beyond.”