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[TomT]

January 25, 2021 SBAU radio hour on KZSB radio 1290AM.
Hosted by Baron Ron Herron (SBAU VP) with President JerryW, Outreach ChuckMcP, and Weebguy TomT.
Agenda suggested by JerryW is below, but download and play the attached MP3 audio file to listen to the actual program.

On 1/23/2021 11:30 PM, Jerry wrote:
>> Radio show of January 25, 2021

> Image.png "When you think about how huge the earth is, and how the earth is just a tiny ball orbiting the sun, which in turn 8is a minscule spec in the universe....it's pretty easy to rationalize eating an entire pie!
>
> This week, while the moon is bright
>    The Red Planet is easy to spot tonight from its perch high in Aries to the south after dark. With a large telescope or video capture capabilities, you may be able to make out features on its 8"-wide disk. The dark Syrtis Major and the large, circular Hellas basin feature centrally on the martian disk around 9 P.M. EST. Keep revisiting the Red Planet as the week progresses — the Moon will remain bright but peel away from the region, offering slightly better contrast with the dark background sky.
>    Just 2° southwest of Mars is the ice giant Uranus. At nearly magnitude 6 and with that bright Moon nearby — just over the border in Taurus — you’ll need at least binoculars to make it out. Look for a grayish “flat” star about half the size of Mars; of course, Uranus is physically much larger, but it sits nearly 20 times farther from Earth than the Red Planet, diminishing its size. Again, revisit this region in the coming days, but know that Uranus will remain a bit harder to find until the Moon’s light is no longer an issue.
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> Looking at asteroids
> Vesta.jpg
> The large asteroid Vesta was one of two worlds the Dawn spacecraft visited. Dawn took this natural-color image of the rocky asteroid in July 2011.
> NASA/JPL/MPS/DLR/IDA/Björn Jónsson
>    Asteroid 4 Vesta, the second-most massive object in the main asteroid belt, currently shines at magnitude 6.8 in the hindquarters of Leo the Lion. It rises around 9 P.M., but wait an hour or two for the region to climb away from the more turbulent air near the horizon. By 10 or 11 P.M., pull out your binoculars to find Vesta just over 4° southwest of Denebola, which marks the tip of the Lion’s tail.
>    Asteroid 14 Irene is near opposition, rising in Cancer the Crab as the Sun sets, so any time after darkness falls is perfect to seek out the small world. You’ll find it glowing at magnitude 9.4 (a perfect binocular object) less that 2° due west of Iota (ι) Cancri, a fourth-magnitude star in the northern part of the constellation.
>
> Monday, January 25
>    Roughly two hours before sunrise, the Moon has finally set and Gemini the Twins are standing upright on the western horizon. The Twins’ heads, Castor (which appears on the right) and Pollux (left), shine brightly about 20° high.
>    They’re roughly the same magnitude (Pollux is a few tenths of a magnitude brighter) but through binoculars or a telescope, you may notice they’re slightly different colors: Castor appears blue-white, while Pollux is a bit more orange-hued. That’s because Castor is a hot type A star, while Pollux is a type K star and slightly cooler than the Sun.
>    But Castor has another advantage over Pollux: sheer numbers. A small telescope will reveal that Castor appears to be not one, but two stars about 4" apart. Called Castor A and B, both are type A stars. However, the Castor family is larger, still — Castor C, which is visible about 70" from A, is a cooler, dimmer type M star orbiting A and B together.
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> Tuesday, January 26
>    Tonight, let’s visit Canis Major, which has cleared the horizon by two hours after sunset. Wait a little longer, and it will rise even higher in the sky.
    Again, the bright Moon is nearby, but tonight we’re seeking out a bright open cluster, NGC 2362, also called the Tau Canis Majoris Cluster after its brightest star: Fourth-magnitude Tau (τ) Canis Majoris. This star dominates the cluster’s light; you’ll need to train binoculars or a small scope on the region to see any of its neighbors. Look about 2.8° east-northeast of Wezen (Delta [δ] Canis Majoris), which marks the top of the Big Dog’s hindquarters, to find the cluster. It covers roughly 8' of sky, although some stars may be hard to spot with the Moon’s brighter background light. (So keep this target in mind and plan to return once the Moon’s phase has progressed.)
>    Tau itself is sometimes called the Mexican Jumping Star, possibly because it always remains relatively low in the sky. That, coupled with its relative brightness, makes it particularly susceptible to scintillation, which occurs when starlight is viewed through Earth’s turbulent atmosphere. This can cause a star to change apparent brightness and even color quite rapidly, sometimes looking as if you’re viewing it through a kaleidoscope. Sirius, the Dog Star, is also subject to this effect when it’s low on the horizon.
>
> Wednesday, January 27
>    With a nearly Full Moon in Cancer tonight, only bright stars are easily visible. After sunset, test your eyesight in Taurus the Bull, who hosts the famous Pleiades star cluster, also cataloged as M45. Most observers can see six or seven stars with the unaided eye, and that might be the most you’ll see tonight. But come back in several days on a darker night and you may see as many as 11 stars without optical aid, depending on the quality of your eyesight.
>    The Pleiades is a young open cluster of stars estimated at just a few tens of millions of years in age. Look to their southeast and you’ll find another open cluster of stars making the “v” of the Bull’s face: the Hyades, one of the closest open star clusters to Earth. Among them shines bright Aldebaran, the eye of the Bull, although this star is not actually part of the cluster. It’s also moving in a different direction on the sky than the cluster, meaning Taurus’ v-shaped visage will eventually start to deform over the next several tens of thousands of years.
>    Keep following a line drawn between the Pleiades and Hyades, and eventually you’ll reach Betelgeuse, the famous red giant star marking the shoulder of Orion the Hunter. This star became recently famous as it underwent a strange dimming event that astronomers attribute to a “stellar sneeze,” in which the star blew out a cool cloud of dust, temporarily blocking some of its light. It’s now back to its original brightness.
>
> Thursday, January 28
> Full Moon occurs at 11:16 A.M. PST; the traditional name for the January Full Moon is the Wolf Moon.
>    During Full Moon, our satellite rises just as the Sun is sinking below the horizon and remains visible all night. Aside from bright stars and planets, the Moon is likely the only thing you’ll be able to observe, so let’s zoom in on some of the features visible during this phase.
>    While the entire nearside of the Moon is on display at this time, it’s also directly illuminated by the Sun, which can wash out certain details. Some of the best spots to focus on during Full Moon include the craters Copernicus and its neighbor Kepler. Copernicus is located in Oceanus Procellarum on the left side of the Moon (when viewed unaided); Kepler is a bit farther to Copernicus’ lower left.
>    The huge crater Tycho is also hard to miss, dominating in the southern region of the Moon with long, bright streaks stretching away from it. These streaks, which also appear around Copernicus and Kepler, are rays of ejecta — material that was thrown up from the surface of the Moon when these features were created, flying as far as 750 to 1,200 miles (1,200 to 1,900 kilometers) from their point of origin.
>    Following in the footsteps of its fellow gas giant earlier this week, Jupiter is in conjunction with the Sun at 6 P.M. PST. It, too, will be visible in the early morning by mid-February.
>
> Friday, January 29
>    Rising only 30 minutes before the Sun, Venus makes for a challenging morning target in the eastern sky. Still, it’s bright at magnitude –3.9, increasing your chances of spotting it. If you can catch it through binoculars or a telescope, you’ll see its disk is roughly 10" across and nearly full (97% lit). Do take care when following it in the brightening sky, however — set an alarm for several minutes before local sunrise and call an end to using any optical aid at that time. This will eliminate the chance of accidentally swinging your optics toward the Sun after it’s risen, which can cause severe and permanent eye damage.
>    Venus’ fellow inferior planet, Mercury, is stationary against the background stars at 9 P.M. EST this evening. Before today, it was tracking northeast; now it will make a U-turn and head southwest. Tonight, you can follow this speedy planet in the west for more than an hour after sunset.
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> Perserverance Rover will land on February 18 in Jezero Crater
https://www.nasa.gov/feature/jpl/7-things-to-know-about-the-nasa-rover-about-to-land-on-mars
 1. Perseverance is searching for signs of ancient life.
>    While the surface of Mars is a frozen desert today, scientists have learned from previous NASA missions that the Red Planet once hosted running water and warmer environments at the surface that could have supported microbial life.
> 2. The rover is landing in a place with a high potential for finding these signs of past microbial life.
>    More than 3.5 billion years ago, a river there flowed into a body of water about the size of Lake Tahoe, depositing sediments in a fan shape known as a delta. The Perseverance science team believes this ancient river delta and lake deposits could have collected and preserved organic molecules and other potential signs of microbial life.
> 3. Perseverance is also collecting important data about Mars’ geology and climate.
>    Context is everything. Mars orbiters have been collecting images and data from Jezero Crater from about 200 miles (322 kilometers) above, but finding signs of ancient life on the surface requires much closer inspection. It requires a rover like Perseverance.
> 4. Perseverance is the first leg of a round trip to Mars.
>    Rather than pulverizing rock the way the drill on NASA’s Curiosity rover does, Perseverance’s drill will cut intact rock cores that are about the size of a piece of chalk and will place them in sample tubes that it will store until the rover reaches an appropriate drop-off location on Mars. The rover could also potentially deliver the samples to a lander that is part of the planned Mars sample return campaign by NASA and ESA (the European Space Agency).
> 5. Perseverance carries instruments and technology that will help pave the way for human missions to the Moon and Mars.
>    Among the future-looking technologies on this mission that will benefit human exploration is Terrain-Relative Navigation. As part of the spacecraft’s landing system, Terrain-Relative Navigation will enable the descending spacecraft to quickly and autonomously comprehend its location over the Martian surface and modify its trajectory.
>    Perseverance will also have more autonomy on the surface than any other rover, including self-driving smarts that will allow it to cover more ground in a day’s operation.
>    In addition, Perseverance carries a technology experiment called MOXIE (short for Mars Oxygen In-Situ Resource Utilization Experiment) that will produce oxygen from Mars’ carbon dioxide atmosphere, for fuel or breathing.
>    Two other instruments will help engineers design systems for future human explorers to land and survive on Mars: The MEDLI2 (Mars Entry, Descent, and Landing Instrumentation 2) package is a next-generation version of what flew on the Mars Science Laboratory mission that delivered the Curiosity rover, while the MEDA (Mars Environmental Dynamics Analyzer) instrument suite provides information about weather, climate, and surface ultraviolet radiation and dust.
>    Perseverance is also giving a ride to the Ingenuity Mars Helicopter. A technology experiment separate from the rover’s science mission.
> 6. The Perseverance rover embodies the NASA – and the scientific – spirit of overcoming challenges.
>    Getting the spacecraft to the launch pad during a pandemic, searching for signs of ancient life, collecting samples, and proving new technologies are no easy feats. Nor is a soft touchdown on Mars: Only about 50% of Martian landing attempts, by any space agency, have been successful.
> 7. You will get to ride along.
>    The Mars 2020 Perseverance mission carries more cameras than any interplanetary mission in history, with 19 cameras on the rover itself and four on other parts of the spacecraft involved in entry, descent, and landing. As with previous Mars missions, the Mars 2020 Perseverance mission plans to make raw and processed images available on the mission’s website.
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> The SBAU Tuesday Telescope Workshop is continuing with a growing attendance. To date participants have included: Tim Crawford, Chuck McPartlan, Gary Peterson, Mike Chibnik, Bob Grueneberg, Henk Aling, Joe Doyle, Robert Richard, Chris Ulivo, Farshad Barman, Jerry Wilson and hosted by our webmaster Tom Totton