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On 12/26/2020 11:56 PM, Jerry wrote the following possible agenda for the SBAU radio hour:
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> This Week
>    The Quadrantid meteor shower, which peaks the morning of January 3, has begun ramping up. Unfortunately, there’s a bright Moon in the sky between now and the shower’s peak; however, given its expected maximum rate of 120 meteors per hour, patient observers still stand a good chance of catching bright shower meteors as the peak approaches. This is particularly true as the Quadrantids often produce bright fireballs — meteors that briefly flare to magnitude –3 or brighter.
>    The shower’s radiant lies in another extinct constellation — Quadrans Muralis. Today, that sits in the constellation Boötes, home to the familiar bright star Arcturus. The region rises after midnight and stands highest in the eastern sky before dawn, so early mornings for the next several days will be the best time to hunt down shower meteors. This shower is associated with two parent bodies: Comet 96P/Machholz and the minor planet 2003 EH1. Its particles streak through the atmosphere at speeds of 26 miles (42 kilometers) per second — medium fast, as far as meteors go.
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> Monday, December 28
>    A week after their Great Conjunction, Jupiter and Saturn are still sharing close quarters in the sky. They’re less than 1° apart, with magnitude –2 Jupiter just east of magnitude 0.6 Saturn.
>    Just like last week, you’ll want to start looking for them low in the southwest as soon as twilight begins to darken the sky because they’re both sinking fast. And just like last week, Ganymede is closing in for another transit across Jupiter’s disk — this one doesn’t start until about 7:30 P.M. PST, however, long after the planet has set for those in the continental U.S.
>    As the gas giants sink below the horizon, look west to see bright Altair in Aquila, now only about 15° high. From Altair, look north-northwest to spot Vega in Lyra; from Vega, gaze east-northeast to find Deneb in Cygnus. These three stars create the familiar Summer Triangle, which gains its name from its position high overhead on summer nights. Now that it’s winter, the Triangle will set earlier and earlier, until its three stars are below the horizon during the cold nighttime hours.
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> Tuesday, December 29
>    Full Moon occurs at 7:28 P.M. PST tonight. Because our bright satellite washes out much of the sky with its glare, consider getting to know some of the terrain on Earth’s closest neighbor instead.
>    The face of the Moon we see from Earth has several dark splotches visible to the naked eye. These are its maria, or seas, although they were never filled with water. Instead, these dark regions are ancient lava flows. Some of the most easily recognizable are Mare Imbrium and Oceanus Procellarum in the lunar west (the Moon’s left side as you see it in the sky), and Mare Serenitatis, Mare Tranquillitatis, and Mare Fecunditatis in the lunar east (the Moon’s right side in the sky).
>    Near the bottom of the Moon is a large crater — Tycho — with long, bright rays of material stretching almost halfway up the face of our satellite. These are made of material thrown up during the impact that formed the crater, which traveled great distances in the Moon’s low gravity to ultimately sink down to the ground much farther away.
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> Wednesday, December 30
>    With a Full Moon still lighting the sky, fainter objects remain hard to find. Instead, search out some of the brighter sky treasures, such as the V-shaped Coma Star Cluster (Melotte 111) in Coma Berenices, which appears above Virgo as they rise in the southeast this morning.
>    By 4 A.M., the cluster is more than 60° high. One of the easiest ways to find it is to first find Leo the Lion, then draw a line between his brightest star, Regulus, and Zosma, which marks the top of his hindquarters. Follow that line about the same distance off to the northwest and you’ll hit the Coma Star Cluster. This young, loose open cluster contains roughly 100 stars less than 300 light-years away. The members range in magnitude from 5 to 10, so while some are visible to the naked eye under dark conditions, your binoculars or telescope will bring out many more.
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> Thursday, December 31
>    Tonight there’s a test for your eyes waiting in the sky. Shortly after dark, Ursa Major is starting to climb her way upward in the sky. By 9 or 10 P.M. local time, her long tail is fully on view; you may recognize this as the kinked handle of the Big Dipper. And right at that kink — the second star from the end — is your challenge. This is the naked-eye binary system Mizar and Alcor. Mizar is magnitude 2, while Alcor is much fainter at magnitude 4. The pair is separated by just 11.8', with Alcor floating slightly northeast of its brighter companion.
>    Many people are able to spot both stars under clear, calm conditions. If you’re having trouble, wait a little while to give the stars time to rise higher above the horizon (where the air can be more turbulent). What’s more, Mizar itself is a binary whose components can be split with a small telescope. Sitting 14" apart, this pair was discovered in 1650. And each of these stars is also a double, although they cannot be visually distinguished.
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> Friday, January 1
>    Ring in the new year with Earth’s sister planet, Venus. It rises as a morning star more than an hour before the Sun this morning, but clings low to the southeastern horizon as dawn brightens the sky. The planet is now located 12° east of the famous star Antares, and 2.5° north-northwest of magnitude 3 Theta (θ) Ophiuchi.
>    Venus is currently on the far side of the Sun from our vantage point, located one and a half times the average Earth-Sun distance from our planet, but only a little over half that distance from the Sun. Its disk appears 94 percent lit and spans 11".
>    Scan northeast a bit and you’ll see some familiar sights — Vega and Deneb, two points of the Summer Triangle, are now rising in the predawn sky. Along with Altair, the Triangle’s third point, they will traverse the sky during daytime for the next few months, until our planet’s journey around the Sun brings us back to the summer season.
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> Ryugu and Bennu.
>    The Hayabusa2 mission successfully collected a sample from a near-Earth asteroid and returned it to Earth -- as well as the first gas sample from deep space, according to the Japan Aerospace Exploration Agency, or JAXA.
>    The sample was dropped off on Earth by a capsule on December 6 in South Australia. Teams from JAXA were able to retrieve the capsule where it landed and conduct some preliminary tests of gas in the capsule before it was sent to Japan.
>    The Hayabusa2 probe accomplished its mission, collecting a sample from the near-Earth asteroid Ryugu and returning it to Earth, according to JAXA.
> The gas was the first step in helping the researchers to confirm that the spacecraft successfully collected a sample from Ryugu in 2019 when the spacecraft visited the asteroid.
>    Researchers confirmed that the gas originated from Ryugu because their analysis of the gas shows that it is different from the atmospheric composition on Earth. Two separate analyses, one in Australia on December 7 and another between December 10 to 11 at the Extraterrestrial Sample Curation Center on the JAXA Sagamihara Campus, helped the teams arrive at the same result.
>    The gas likely came from the collected material on the surface and beneath the surface of the asteroid itself. The researchers will continue opening the capsule containing the sample to understand more about the gas.
>    The team also confirmed that black sand grains are also inside the sample container, further confirmation that there is asteroid material inside the capsule.
>    By the end of 2021, JAXA will share tiny samples from Ryugu to six teams of scientists across the globe. Meanwhile, Hayabusa2 continues on its path after flying by Earth in early December to drop off the capsule and will visit more asteroids in the future.
>    Hayabusa2 launched on December 3, 2014, and arrived at the near-Earth asteroid Ryugu in June 2018. The spacecraft collected one sample from the asteroid's surface on February 22, 2019, then fired a copper "bullet" into the asteroid to create a 33-foot wide impact crater. A sample was collected from this crater on July 11, 2019.
> Then, Hayabusa2 departed the asteroid in November 2019 and journeyed back to Earth.
>    Altogether, the mission's scientists believes one gram of material was collected, but they can't be sure until they open it completely. “One gram may sound small, but for us, one gram is huge," said Masaki Fujimoto, deputy director general of the department of solar system sciences at JAXA, during an online briefing hosted by the Australian Science Media Centre. "It is enough to address our science questions."
>    The agency's first Hayabusa mission returned samples from the asteroid Itokawa to Earth in June 2010, but scientists said that due to failure of the spacecraft's sampling device, they were only able to retrieve micrograms of dust from the asteroid.
>    “Ryugu is linked to the process that made our planet habitable," Fujimoto said. "Earth was born dry; it didn't begin with water. We think distant bodies like Ryugu came to the inner part of solar system, hit Earth, delivered water and made it habitable. That's the fundamental question we're after and we need samples to solve that."
> Asteroids are like leftovers from the formation of our solar system, preserving information about the origins of planets as well as the vital elements that allow life to exist on Earth.
>    The NASA OSIRIS-REx mission recently collected a sample from another near-Earth asteroid, Bennu, that is similar in composition to Ryugu. In fact, based on early data from both missions, scientists working on both missions believe it's possible these two asteroids once belonged to the same larger parent body before it was broken apart by an impact.
> The Bennu sample will be returned to Earth by 2023.       
> Patrick Michel, director of research at the French National Centre for Scientific Research in Paris, is an investigator for both missions.
> "It is really important to realize that no two asteroids are the same," Michel told CNN in October. "Even if Bennu and Ryugu share some intriguing similarities and belong to the same category (primitive), they also have some very interesting differences. And these samples will occupy generations of researchers as a large amount will be kept for future generations that will benefit from the increase in technology and accuracy of the instruments used to analyze them."