Friday, February 7, 2020

Idaho Skies Transcript for the weekend of February 14th


STEPHEN
Welcome to Idaho Skies for the weekend of February 14th. We’re your hosts, Stephen…

DAN
…and Dan.

STEPHEN
The moon reaches the third quarter phase this weekend, so it’s a perfect time to go moon gazing with your binoculars. The only problem is that you need to go outside after midnight to see it. But hey, it’s a weekend, so no problem. Observing the moon however will more convenient for listeners who get up before sunrise.

DAN
At third quarter, we’re able to see the moon’s western hemisphere. This hemisphere contains the moon’s largest feature, the Ocean of Storms. The Ocean of Storms is that lunar sea covering most of its western edge. Its 1,600 miles from the north to the south, or nearly the same height as the continental United States. 

STEPHEN
On the morning of the 15th, the last quarter moon appears next to a star in Libra the Scales named Zubenelgenubi. This funny sounding name means the Southern Claw. The name doesn’t make sense for a constellation representing a set of scales for weighing objects. However, the star originally belonged to Scorpius the Scorpion. 

DAN
Most stars, like Zubenelgenubi are multiple stars, or stars in orbit around each other. However, it’s a special double star. That’s because its stars are so different (distant) from each other and the pair is so close to the solar system. This combination makes the pair appear farther apart than most double stars. So aim your binoculars at the star to the moon’s right and see if you see double.    

STEPHEN

That’s Idaho Skies for the weekend of February 14th.   

DAN
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Dan…

STEPHEN
…and Stephen.

DAN
Dark skies and bright stars.

Idaho Skies Transcript for the week of February 10th


PAUL
Welcome to Idaho Skies for the week of February 10th. We’re your hosts, Paul…

STEPHEN
…and Stephen.

PAUL
Tiny Mercury makes an appearance this week. Few people have seen this elusive planet because it never appears very far above the horizon. This week however, the planet reaches its highest elevation above the western horizon. The planet can be quite bright, so it’s not difficult to see, if you know where to look.   

STEPHEN
Use Venus as your guide. Go outside at 7:00 PM and look for Venus, or the Evening Star. It’s the brightest object in the west-southwest, so you can’t miss it. Mercury, which is closer to the sun, is located to the lower right of Venus. Mercury is the only object appearing below Venus and at a point due west above the horizon.  

PAUL
Mercury is a small rocky world with a diameter of 3,000 miles. That makes it a bit larger than the moon and less than half the size of the Earth. Without an atmosphere, the surface of Mercury is pummeled with meteoroids. Its surface is so cratered than it easy to mistake Mercury for the moon. 

STEPHEN
Mercury was first visited by the Mariner 10 spacecraft in 1974. The 1,000-pound spacecraft didn’t carry enough propellant to slow down. That means Mariner 10 flew past Mercury collecting data and pictures. However, Mariner 10 was in orbit around the sun, so the spacecraft was able to visit Mercury two additional times.

PAUL
That’s Idaho Skies for the week of February 10th.  

STEPHEN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Stephen…

PAUL
…and Paul.

STEPHEN
Dark skies and bright stars.

Monday, February 3, 2020

Idaho Skies Transcript for the weekend of February 7th


BENJAMIN
Welcome to Idaho Skies for the weekend of February 7th. We’re your hosts, Benjamin…

PAUL
…and Paul.

BENJAMIN
On the last show, we talked about globular star clusters. This week, the moon passes close to a galactic star cluster and we think listeners should observe it. So let’s talk about these star clusters and how to see a nice one this week. Imagine before the invention of the telescope, when people only saw a small and fuzzy cloud in (the) Cancer the Crab.  

PAUL
This nebula was called the Praesepe. It was pictured as a manager holding hay for two donkeys. In this story, the donkeys were represented by the two faint stars next to the nebula. Until Galileo observed this fuzzy patch with his telescope, that’s all the ancients knew of it. When Galileo aimed a telescope at it, he counted over 40 stars inside of this cluster.      

BENJAMIN
Galileo’s telescope was too small to see the over 1,000 stars making up the Praesepe. He also didn’t know that the stars in the Praesepe formed together from the same cloud of dust and gas some 650 million years ago. Because of its large size and low density, the stars of the Praesepe cluster will eventually escape the cluster.       

PAUL
You still have lots of time to see this cluster, however. So aim your binoculars at the moon on the 8th after it rises well above the eastern horizon. If the moon is at the top of your view, then the Praesepe will be located just beneath the center of your view. Once you see this cluster through binoculars, you’ll realize why it’s now called the Beehive star cluster.   

BENJAMIN
That’s Idaho Skies for the weekend of February 7th.

PAUL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Paul…

BENJAMIN
…and Benjamin.

PAUL
Dark skies and bright stars.

Idaho Skies Transcript for the week of February 3rd


DAN
Welcome to Idaho Skies for the week of February 3rd. We’re your hosts, Dan…

BENJAMIN
…and Benjamin.

DAN
On Monday night, the moon drifts through the edge of the Hyades star cluster. The Hyades is one of the largest star clusters in our sky. Star clusters like this are called galactic star clusters and they formed recently from a cloud of dust and gas. Over time, the dust and gas dissipates and the stars drift apart.

BENJAMIN
Galactic star clusters have the appearance of a random scattering of stars. This is the opposite of another type of star cluster, the globular star cluster. Globulars are spherical in shape and much older than galactics. Sadly, there are no globular star clusters close enough to appear as anything but a fuzzy spot through binoculars.

DAN
If the sun was a member of a globular star cluster, then our night-time sky would be filled with thousands of bright stars. There would be no night, and the sky would always be filled with light. Unfortunately, there may be no planets inside of globular clusters. That’s because of the typical age of globular star clusters.     

BENJAMIN
Globular star clusters are filled with old stars, formed when only hydrogen and helium filled the universe. Over time, these early stars fused elements into heavier ones like carbon, oxygen, and iron. But without these heavier elements, planets and even life can’t form. So chances are that no one is enjoying the amazing view inside of a globular cluster.

DAN
That’s Idaho Skies for the week of February 3rd.   

BEJAMIN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Benjamin…

DAN
…and Dan.

BENJAMIN
Dark skies and bright stars.

Monday, January 27, 2020

Idaho Skies Transcript for the weekend of January 31st


STEPHEN
Welcome to Idaho Skies for the weekend of January 31st. We’re your hosts, Stephen…

DAN
…and Dan.

STEPHEN
The moon is at the perfect phase this weekend. That’s the first quarter moon, or when Earth can only see half of the illuminated moon. Remember,  that half of the moon is always experience day. However, this weekend, half of the illuminated side is located on the far side and thus we cannot see it.  

DAN
What makes the first quarter moon so perfect for observing is that the shadows cast by the rising sun appear stretched out to their maximum extent. And those shadows are visible along the lunar terminator.

ARNOLD
I’ll be back

DAN
No, not that kind of terminator. Astronomically speaking, the terminator is the boundary between day and night. And when it’s turned face on to Earth, shadows appear at their greatest angular extent.

STEPHEN
Scan this area with your binoculars or small telescope this weekend. You’ll see mostly craters in the moon’s Southern Hemisphere and lunar seas in the north. Those lunar seas are ringed with mountains where the lunar crust was thrown back by massive impacts billions of years ago.    

DAN
There’s an extra treat on Sunday. That night the moon will be flanked by two star clusters, the Pleiades and the Hyades. The Pleiades is the smaller of the two and it’s a wonderful target for binoculars. The star cluster is 444 light years away. So the Pleiades that you see tonight is what it looked like in 1576.

STEPHEN
That’s Idaho Skies for the weekend of January 31st.    

DAN
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com

For Idaho Skies this is Dan…

STEPHEN
…and Stephen.

DAN
Dark skies and bright stars.

Idaho Skies Transcript for the week of January 27th


PAUL
Welcome to Idaho Skies for the week of January 27th. We’re your hosts, Paul…

STEPHEN
…and Stephen.

PAUL
German astronomer Johannes Hevelius was born on the 28th in 1611. Since most of our listeners are not familiar with this astronomer, let’s talk about him and his telescopes. Johannes was originally a beer brewer. Then after studying jurisprudence, he settled down in his hometown to become an astronomer. 

STEPHEN
In 1641, Johannes started building telescopes on the roofs of building. Since lens back then were of poor quality, astronomers had to compensate by increasing their focal lengths. For example, one of Johannes’ first long telescopes was twelve feet long. And his telescopes were about to get a lot larger than that.     

PAUL
And by large, we mean large. Johannes eventually made telescopes 60 and 70 feet long. He even built a telescope 150 feet long in 1673. These were called aerial telescopes and they had open tubes. The lenses were held in place with a series of wires. It took a crew to move these telescopes around. 

STEPHEN
Johannes was encouraged to use his telescopes to collect data. Unfortunately, the long and cumbersome telescopes were not a good fit for this. Nonetheless, he did spend four years making lunar maps. They were spectacular for the time and today we still consider Johannes the founder of lunar topography.

PAUL
That’s Idaho Skies for the week of January 27th.   

STEPHEN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Stephen…

PAUL
…and Paul.

STEPHEN
Dark skies and bright stars.

Monday, January 13, 2020

Idaho Skies Transcript for the Weekend of January 17th


STEPHEN
Welcome to Idaho Skies for the weekend of January 17th. We’re your hosts, Stephen…

DAN
…and Dan.

STEPHEN
The moon reaches third quarter on the 17th. Late sleepers and early risers will find the half full moon in the east while it’s still dark. Since the moon is half full, the shadows cast by the rising sun strongly accentuate lunar features like craters and mountains. Stargazers with binoculars will want to aim them at the moon on the 17th.   

DAN
Lunar craters where one time thought to be volcanic in nature. Observations of bullets striking the ground gave no indication that craters could form from impacts. The error was assuming that a “slow” bullet behaved like a meteoroid colliding with the ground at hypersonic speeds.  

STEPHEN
At impact though, a meteoroid vaporizes the ground in the immediate area. Land farther away gets peeled back and then flipped over. This means the closer an astronaut walks to a crater’s rim, the deeper the rock layers originated. Therefore, one need not actually climb down into a crater to get deep rock samples. 

DAN
Many of the craters you’ll see on the moon formed during the late heavy bombardment, or around 3.8 billion years ago. This was a time when planets and moons were sweeping up planetary building blocks. These building blocks are called planetesimals and they condensed from the original gas and dust of the solar system.

STEPHEN
That’s Idaho Skies for the weekend of January 17th.   

DAN
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Dan…

STEPHEN
…and Stephen.

DAN
Dark skies and bright stars.

Idaho Skies Transcript for the Week of January 13th


PAUL
Welcome to Idaho Skies for the week of January 13th. We’re your hosts, Paul…

STEPHEN
…and Stephen.

PAUL
Fifteen years this Tuesday, the Huygens space probe landed on Titan. So let’s talk about Huygens and Titan. But first, the Cassini spacecraft was launched to Saturn back in October 1997. The spacecraft then spent 6.5 years traversing the solar system to reach Saturn. Once there, it fired its thrusters and entered orbit.

STEPHEN
On December 25th 2004, Cassini released the Huygens probe. Huygens was riding piggy-back on the spacecraft and didn’t carry its own set of thrusters. This means Cassini had to aim for Titan before the release and then fire its thrusters afterwards to miss Titan. Titan by the way is Saturn’s largest moon.

PAUL
What makes Titan so special and interesting is that it has a dense atmosphere. In fact, it’s 50% denser than our atmosphere. Like our atmosphere, Titan’s is mostly nitrogen. Unlike ours, Titan’s atmosphere has no oxygen and its freezing cold. On its surface, the temperature is -290 degrees Fahrenheit.  

STEPHEN
Huygens returned images of an icy landscape of hills, dunes, and drainage patterns. Since Titan’s surface is bitterly cold, water ice is as hard as granite. Methane, a gas also on Earth, is a liquid on Titan. The moon therefore has a geological cycle of water and a hydrological cycle of methane. Still, Huygens returned landscape images looking very similar to Earth. 

PAUL
That’s Idaho Skies for the week of January 13th.  

STEPHEN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Stephen…

PAUL
…and Paul.

STEPHEN
Dark skies and bright stars.

Monday, January 6, 2020

Idaho Skies Transcript for the Weekend of January 10th


STEPHEN
Welcome to Idaho Skies for the weekend of January 10th. We’re your hosts, Stephen…

PAUL
…and Paul.

STEPHEN
Hey, the moon is full on the 10th. Did you know that some Native American tribes named the first full moon of January the Wolf Moon? They did because on cold winter nights, wolves are hungrier than usual. So the people of these cultures would hear wolves howling more frequently at night.

PAUL
The full moon illuminates the sky and washes away all the fainter stars. That means the nights near the full moon are bad times to look for faint and fuzzy astronomical objects like comets and nebulae. Therefore, check out the sky tonight and see how the moon’s light changes the sky from dark black to grayish blue.  

STEPHEN
Then get out your binoculars for the night of the 11th. The Beehive star cluster will be three degrees to the upper right of the moon. Since binoculars have a field of view of 7.5 degrees, both the moon and star cluster will appear together. However, it will be better if you shift the moon out of the field of view.

PAUL
The Beehive star cluster appears as large as the moon, so it’s not very small. You’ll see a compact groping of some two dozen stars, once the moon is out of sight. People call this star cluster the Beehive because it has a strong resemblance to bees buzzing around their hive. Do you see the same thing?   

STEPEN
That’s Idaho Skies for the weekend of January 10th.

PAUL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Paul…

STEPHEN
…and Stephen.

PAUL
Dark skies and bright stars.

Idaho Skies Transcript for the Week of January 6th


DAN
Welcome to Idaho Skies for the week of January 6th. We’re your hosts, Dan…

PAUL
…and Paul.

DAN
Earth just passed perihelion this week. So let’s discuss perihelion and what it means for Earth. Perihelion is that point in an elliptical orbit that is closest to the sun. At perihelion, Earth is only 91 million, 343 thousand miles from the sun. Or about 2% closer than average.

PAUL
Even though Earth receives about 7% more sunlight at perihelion, it occurs over the Southern Hemisphere. The Southern Hemisphere, which is covered mostly by water, is difficult to warm up. Therefore, all that extra sunlight can’t warm air temperatures in the Southern Hemisphere very significantly.  

DAN
On the 7th, stargazers will find the waxing gibbous moon near the eye of the celestial bull. That bull is named Taurus and his eye is named Aldebaran. Taurus is an old constellation. In fact, this pattern of stars was recognized as a bull all the way back to the Bronze Age, over 6,000 years ago.    

PAUL
The distance between the moon and Aldebaran is five degrees. Since binoculars have a field of view of around 7.5 degrees, the moon and Aldebaran will be seen together. But notice that Aldebaran has company. To the right of Aldebaran and a little above are the stars of the Hyades star cluster.

DAN
That’s Idaho Skies for the week of January 6th.  

PAUL
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Paul…

DAN
…and Dan.

PAUL
Dark skies and bright stars.

Tuesday, December 17, 2019

Idaho Skies Transcript for the weekend of December 20th


STEPHEN
Welcome to Idaho Skies for the weekend of December 20th. We’re your hosts, Stephen…

DAN
…and Dan.

STEPHEN
Astronomically speaking, winter begins on the 21st at 9:19 PM. At that time, the sun appears its farthest south of Earth’s equator. With the sun that low in our sky, the days are their shortest and the sun’s light its most spread out. The combination of low sunlight intensity, short days, and long nights make our winter weather very cold.

DAN
The sun’s position in the sky drifts north during the winter and spring and then south during summer and autumn. When the sun reaches its northerly or southerly extreme, astronomers call it a solstice. The word solstice means sun standing still because on those days, the sun’s movement north and south appears to halt for a few days. 

STEPHEN
At 6:00 AM the morning after the winter solstice, stargazers will find the moon seven degrees above Mars. Seven degrees is a little less than the width of your fist when viewed at the end of your outstretched arm. Mars won’t be very bright since is 209 million miles. That’s just too far away for the reflected light of such a small planet.  

DAN
Slightly fainter and closer to the moon’s left is a star named Zubenelgenubi. That’s a funny sounding name for a star that’s really a pair of stars. Good binoculars can split this star into two. Some people in fact may have good enough vision that they can split it without optical aid. Are you one?

STEPHEN
Not me.

That’s Idaho Skies for the weekend of December 20th.   

DAN
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Dan…

STEPHEN
…and Stephen.

DAN
Dark skies and bright stars.

Idaho Skies Transcript for the week of December 16th


PAUL
Welcome to Idaho Skies for the week of December 16th. We’re your hosts, Paul…

STEPHEN
…and Stephen.

PAUL
This week marks the beginning of the Ursid meteor shower. Haven’t hear of it? Well, not many people have. It’s a weak shower that only produces ten meteors per hour on average. Its parent body is comet Tuttle. And as this comet approaches the sun, the sun’s heat vaporizes the comet’s surface to release fine dust that can becomes meteors.

STEPHEN
Astronomers know that the Ursids can produce over 100 meteors per hour on occasion. That’s because the gravitational pull of Jupiter concentrates the meteor stream in places. When this is going to occur, astronomers can’t accurately predict. Therefore, it might be worth your while to look for this meteor shower occasionally this week. 

PAUL
Listeners observing this shower need to identify meteors originating from the north. Specifically, from the brightest star in the bowl of the Little Dipper. That star’s name is Kochab. Kochab is slightly fainter than its more famous brethren, Polaris on the other end of the Little Dipper.   

STEPHEN
On the morning of the 17th, stargazers will find the nearly third quarter moon close to the star Regulus. That’s the brightest star in Leo the Lion. Then late on the night of the 18th, you can use your binoculars to observe the craters long the terminator of the half full moon. So there are two lunar events that you can enjoy this week.

PAUL
That’s Idaho Skies for the week of December 16th.  

STEPHEN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Stephen…

PAUL
…and Paul.

STEPHEN
Dark skies and bright stars.

Monday, December 9, 2019

Idaho Skies Transcript for the weekend of December 13th


BENJAMIN
Welcome to Idaho Skies for the weekend of December 13th. We’re your hosts, Benjamin…

PAUL
…and Paul.

BENJAMIN
The moon visits Pollux, one of the Gemini Twins on the 13th. Twin brother Pollux is the row of stars on the left and right sides of the moon. Its brightest star, also named Pollux, is on the left and it represents the head of this celestial brother. In the Gemini myth, Pollux is the immortal brother of the two. 

PAUL
This weekend, the Geminid meteor shower reaches its peak intensity. Stargazers can normally expect to see upwards of 100 meteors per hour from this shower. The meteoroids of this shower travel so fast that they create white-hot shock waves. So that meteor streak you see is really the thin atmosphere glowing white hot from the passage of the meteoroid.  

BENJAMIN
Unfortunately, the nearly full moon rises in Gemini. That’s the same constellation that the Geminid meteor shower originates from. Therefore, strong moon light will out-shine most of the meteors of this shower. Your best bet to see Geminids therefore is to look for them overhead and not in the east where the moon is located.

PAUL
On Sunday night, you’ll find the moon a short distance from the Beehive star cluster. So get your binoculars out and aim them at the moon. Then shift them downwards until the moon leaves the view at the 1 o’clock position. At the bottom of your view will be a cluster of over a dozen tightly packed stars.

BENJAMIN
That’s Idaho Skies for the weekend of December 13th.

PAUL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Paul…

BENJAMIN
…and Benjamin.

PAUL
Dark skies and bright stars.

Idaho Skies Transcript for the week of December 9th

DAN
Welcome to Idaho Skies for the week of December 9th. We’re your hosts, Dan…

BENJAMIN
…and Dan.

DAN
Because it travels around the heavens in 30 days, the moon makes a great astronomical guide. However, it’s restricted to the path taken by the sun and planets, or the constellations of the Zodiac. Since the Pleiades and Hyades star clusters are located in Taurus the Bull, the moon visits them monthly. 

BENJAMIN
So go outside on the 9th to locate the Pleiades above the moon. Then again on the 10th to find the moon inside the Hyades star cluster. Both star clusters are ideal binocular objects. As long as the moon’s light doesn’t interfere with the fainter stars, you’ll see at least two dozen stars in each cluster.   

DAN
Moonlight is a problem, however, because the moon is full on the 11th. The full moon can be blinding through a telescope or even binoculars. After looking at the moon, don’t be surprised if you can’t see faint objects as well as you could before. Fortunately, this effect goes away in a few minutes.

BENJAMIN
You will hardly see any craters on the full moon. There are two reasons for this. First, when the sun is overhead, it casts few shadows. And two, Earth and the sun appear in the same place from the moon’s perspective. That means any shadows cast by sunlight are covered up by the terrain creating the shadows in the first place.      

DAN
That’s Idaho Skies for the week of December 9th.  

BEJAMIN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Benjamin…

DAN
…and Dan.

BENJAMIN
Dark skies and bright stars.

Monday, December 2, 2019

Idaho Skies Transcript for the weekend of December 6th


STEPHEN
Welcome to Idaho Skies for the weekend of December 6th. We’re your hosts, Stephen…

DAN
…and Dan.

STEPHEN
On the 8th, Comet Borisov reaches perihelion. So let’s talk about perihelion and Comet Borisov. The word perihelion comes from the Greek “peri” and that’s the prefix meaning “about” or “around”. Think of the word perimeter as an example. And the word Helion comes from the word Helios, which is the Greek name for the sun.     

DAN
Perihelion can only occur for objects that travel in non-circular orbits. That means at perihelion, objects like Comet Borisov pass their closest to the sun. However, Comet Borisov has an orbit that’s a bit odd - it’s hyperbolic and not elliptical in shape. That means the orbit of Borisov doesn’t begin nor end in our solar system. 

STEPHEN
Comet Borisov is traveling so fast that it will escape our solar system. It didn’t pick up this speed from a close pass to another planet in our solar system. Instead, it’s traveling so fast because it escaped from another star system and fell into ours. The gravity of another object in its original solar system must have kicked it into interstellar space. 

DAN
Astronomers predict that there’s at least one interstellar visitor in our solar system at any given time. They approach the sun in a hyperbolic orbit and then fly away to never be seen again. Currently, visits by interstellar objects are the best way we can study the materials and formation of other solar systems.

STEPHEN
That’s Idaho Skies for the weekend of December 6th.  

DAN
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com

For Idaho Skies this is Dan…

STEPHEN
…and Stephen.

DAN
Dark skies and bright stars.

Idaho Skies Transcript for the week of December 2nd


PAUL
Welcome to Idaho Skies for the week of December 2nd. We’re your hosts, Paul

STEPHEN
…and Stephen.

PAUL
It’s easy to be a rock star when there are no bright stars near you. And that’s definitely true for Fomalhaut, the star below the moon on the 3rd. Astronomers rate Fomalhaut as first magnitude. It was the ancient Greeks who designed this magnitude system as a way to classify stars by their apparent brightness.

STEPHEN
They designed the magnitude system to start with a one for the brightest stars and six for the faintest the unaided eye can see. There are 17 stars brighter than Fomalhaut and some of them have negative magnitudes. For example, Sirius, the bright star rising at 9:45 PM this evening is magnitude is -1.5.   

PAUL
The moon reaches first quarter minutes before midnight of the 4th. That means it looks so close to first quarter on the 3rd that you won’t see the difference. First quarter occurs when the angle between the sun, Earth, and moon is 90 degrees. So the moon is nearly due south as the sun sets in the southwest.

STEPHEN
Recall that the sun always illuminates exactly half of the moon. Therefore, at first quarter we can only see half of the illuminated lunar surface. Lunar seas or lava plains cover much of the northern half that we can see and craters fill the southern half. This makes the first quarter phase the perfect moon for exploring with binoculars.   

PAUL
That’s Idaho Skies for the week of December 2nd.  

STEPHEN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Stephen

PAUL
…and Paul.

STEPHEN
Dark skies and bright stars.

Monday, November 18, 2019

Idaho Skies Transcript for the weekend of November 22nd


STEPHEN
Welcome to Idaho Skies for the weekend of November 22nd. We’re your hosts, Stephen…

BENJAMIN
…and Benjamin.

STEPHEN
The moon appears as a thin crescent 6:30 on the morning of the 23rd. Thin moon’s like this are cool to see and are even more attractive through binoculars. But wait, it gets even better on the Saturday morning. That’s because Mars and the brightest star of Virgo the Maiden are close at hand. 

BENJAMIN
Recall that Mars currently resides on the other side of the solar system. That means it will be much fainter than it typically appears. In fact, it might be faint enough that it’s famous orange-tint may not be apparent. But still, it’s worth looking for Mars now and watching how it gets brighter over the months.  

STEPHEN
Brighter than Mars will be Spica, the lucida of Virgo. You can’t misidentify the two. Mars will be fainter of the two and below the moon. Spica will be brighter, purer white in tint, and to the moon’s lower right. Spica is actually two stars so close together that their mutual gravities warp them into egg shapes.

BENJAMIN
Stargazers not wanting to get up early will want to look in the low southwest as it’s getting dark. This weekend, Jupiter passes close to Venus with their smallest gap occurring on Sunday evening. Venus will appear much brighter than Jupiter, so it’s easy to distinguish which planet is which.

STEPHEN
That’s Idaho Skies for the weekend of November 22nd.  

BENJAMIN
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Benjamin…

STEPHEN
…and Stephen.

BENJAMIN
Dark skies and bright stars.

Idaho Skies Transcript for the week of November 18th


PAUL
Welcome to Idaho Skies for the week of November 18th. We’re your hosts, Paul…

STEPHEN
…and Stephen.

PAUL
The moon reaches third quarter this week. That means the moon only appears half full. But this time, it’s the western half of the moon that appears illuminated. Like the first quarter moon, shadows along the lunar terminator really bring out terrain features like craters and mountains. So concentrate your attention there. 

STEPHEN
There’s just one problem with observing the third quarter moon – it rises so late. You’ll need to go outside at around 1:00 AM to see the moon rise over the Boise mountain range. Stargazers observing the third quarter moon see a portion few people ever see. For example, its largest lunar maria, the Ocean of Storms.

PAUL
The Ocean of Storms fills the entire left edge of the moon. It’s the landing location of Apollo 12 back on late 1969. The crater of the ocean’s right edge is called Copernicus. It’s an impact scar 57 miles across. Astronomers estimate that the crater is relatively young at 800 million years old. That’s young for the moon.

STEPHEN
Moon watchers will find the third quarter moon inside Leo the Lion on the morning of the 20th. Leo’s brightest star, Regulus is located to the moon’s right. The lion’s mane is the question mark of stars above Regulus. Farther away to the left is fainted Denebola. Denebola represents the base of Leo’s tail. 

PAUL
That’s Idaho Skies for the week of November 18th.  

STEPHEN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Stephen…

PAUL
…and Paul.

STEPHEN
Dark skies and bright stars.

Idaho Skies Transcript for the week of November 11th


BENJAMIN
Welcome to Idaho Skies for the week of November 11th. We’re your hosts, Benjamin…

DAN
…and Dan.

BENJAMIN
The full moon travels past two bright and large star clusters this week. The first cluster is the Pleiades. You probably know the Pleiades as the Seven Sisters, but astronomers have an official designation, M-45. M-45 is a close star cluster. So it appears large and bright in the night sky. The moon will make a distant pass of the cluster later this week.  

DAN
Get your binoculars and observe M-45. Be sure to compare the view of the Pleiades to your unaided eye and through binoculars. If you’re like most people, you’ll see six or maybe seven stars with just your eyes. However, with binoculars the number of stars explodes. You might see as many as two dozen glittering stars.

BENJAMIN
On the 13th, our moon makes it way to the Hyades star cluster. The Hyades are closer to our solar system then the Pleiades. Unfortunately, the star cluster is sparser and therefore, less dazzling. Still, binoculars will show stargazers some two dozen stars in this cluster. But don’t be fooled by its brightest star. 

DAN
The ancients named the brightest star of Taurus Aldebaran. And it just so happens to appear in the same view as the Hyades. However, Aldebaran is only half as far away as the Hyades. So from Earth, it only looks like Aldebaran is a member of the Hyades. Because of its reddish tint, people consider Aldebaran to be the eye of Taurus the Bull.

BENJAMIN
That’s Idaho Skies for the week of November 11th.  

DAN
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is DAN…

BENJAMIN
…and Benjamin.

DAN
Dark skies and bright stars.

Idaho Skies Transcript for the weekend of November 15th


DAN
Welcome to Idaho Skies for the weekend of November 15th. We’re your hosts, Dan…

PAUL
…and Paul.

DAN
This weekend the moon passes through Gemini the Twins and ends up in Cancer the Crab. On Friday, the moon appears next to Castor’s knee and foot. Since Gemini rises in the east lying on its side, Castor is the top twin this weekend. Castor is also the name of the fainter of the two brightest stars making up Gemini.

PAUL
On Saturday night, you’ll find the moon closer to the head of Pollux, the lower and brighter star of the Heavenly Twins. It’s odd that astronomers named Pollux Beta Geminorum. Because calling a star the beta star of a constellation typically signifies that its second brightest star.   

DAN
While it doesn’t take a pair of binoculars to see Castor or Pollux, the moon’s neighbor on Sunday will. If you aim your binoculars at the moon at around 11:30 PM, you’ll find a scattering of stellar gems just below it. That’s the Beehive star cluster and it’s even visible without optical aid in very dark skies. 

PAUL
Many ancient cultures were aware of the Beehive. Some of them referred to this tiny cloudy spot as a manager. They called objects like the Beehive a nebula, which means small cloud. Galileo was the first to discover that optical aid turned the Beehive into a star cluster in 1609. 

DAN
That’s Idaho Skies for the weekend of November 15th.

PAUL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Paul…

DAN
…and Dan.

PAUL
Dark skies and bright stars.