Tuesday, April 21, 2015

Transcript for April 19 to 25

RACHEL
Welcome to Idaho Skies for the fourth week of April. We’re your hosts, Rachel... 

PAUL
 ...and Paul.

 RACHEL
Like all stars, Aldebaran, the alpha star of Taurus the Bull is moving closer to the western horizon every night. 

PAUL
Since Venus is a planet, it’s moving away from the horizon every night.

RACHEL
That is at least until June when Venus begins passing between Earth and the sun.

PAUL
Therefore, it’s not surprising to hear that these two celestial objects cross paths on occasion. 

RACHEL
You’ll find Venus on the outskirts of the Hyades star cluster and therefore close to Aldebaran on the evening of the 20th.

PAUL
When you go out to see them, be sure to look for the young and very thin crescent moon close to the horizon.

RACHEL
Two days later, Aldebaran, the moon, the Pleiades, and Venus form a compact grouping.

PAUL
The grouping is so small that you can just about cover them with your outstretched hand on the 21st. 

RACHEL
That’s a bunch of binocular objects for the choosing and you don’t have to scan the rest of the sky to see them.

PAUL
Mercury has traveled its greatest distance away from the sun and is now inching its way back. 

RACHEL
Before long, it will be too close to the horizon and sun to be visible in the evening.

PAUL
On its way back to the sun, the innermost planet passes close to Mars on the 22nd.

RACHEL
Mercury is brighter than Mercury, so you can’t confuse them.

PAUL
At 8:30 PM on the 22nd, scan the sky close to the horizon and to the lower right of Venus.

RACHEL
The first star you’ll find is Mercury.

PAUL
Mars will be the fainter star located to the lower left of Mercury.

RACHEL
It’s been three months since we’ve had the opportunity to watch a meteor shower and quite frankly, we’re overdue.

PAUL
During the last week of April, the Lyrid meteor shower picks up its level of activity.

RACHEL The meteor shower reaches its peak activity on the night of the 22nd and morning of the 23rd.

PAUL
Meteors from this shower will appear to originate from the northeast and become more numerous after midnight.

RACHEL
Fortunately, this year the moon is a thin crescent on the 22nd and it therefore sets before midnight. 

PAUL
On the down side, this is not one of the best meteor showers of the year.

RACHEL
You can only expect to see some ten meteors per hour from this shower.

PAUL
But hey, since our last meteor shower occurred in January, the Lyrids aren’t bad.

RACHEL
The Beehive star cluster is one of the nicest star clusters for binocular viewing.

PAUL
This star cluster is easy to see, but it’s located in a rather blank part of the sky.

RACHEL
So it’s really helpful to have the moon show you its location.

PAUL
On the 25th, scan straight up along the moon’s terminator or the boundary between lunar day and night, until you run into the cluster.

RACHEL
The star cluster will look like a sprinkling of diamond dust in your binoculars.

PAUL There’s another, smaller star cluster nearby called M-67.

RACHEL
And you’ll be able to find this star cluster by keeping in mind that Jupiter, M-67, the moon, and the Beehive star cluster form a square.

PAUL
That’s Idaho Skies for the fourth week of April. Next week we’ll compare two blue-white stars that the moon passes.

RACHEL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps. For Idaho Skies this is Rachel...

PAUL ...and Paul.

RACHEL
Dark skies and bright stars.

Sunday, April 12, 2015

Transcript for April 12 - 18

RACHEL Welcome to Idaho Skies for the third week of April. We’re your hosts, Rachel... PAUL ...and Paul. RACHEL The first human to travel into space did so on April 12th, 1961. PAUL His name was Yuri Gagarin and he was a 27 year old pilot of the Soviet Air Force. RACHEL This came as a bit of a surprise to the United States, which was planning to launch American astronauts during Project Mercury. PAUL In fact, if it hadn’t been for concerns about earlier Redstone tests and bad weather, we might have beaten the Soviets and put the first man into space. RACHEL However, Yuri’s flight was significantly different from the first two American flights. PAUL That’s because Yuri actually made one orbit around Earth before returning in his Vostok space capsule. RACHEL The United States launched its first two astronauts using converted Redstone missiles. PAUL And these missiles didn’t have the power to place a Mercury space capsule into orbit. RACHEL That’s why the first two American astronauts were only lobbed 115 miles up before descending back to the Atlantic Ocean. PAUL The reason the Soviets were able to put Yuri into orbit is that their R-7 missile was much larger and powerful than the Redstone. RACHEL Because of concerns they might fail, the Soviets didn’t announce Yuri’s mission until 52 minutes into his flight. PAUL And less than 40 minutes later, he had fired his retro rockets and was returning back to Earth. RACHEL The Mercury capsules returned to Earth by splashing down into the ocean, however the Vostok 1 landed on the ground. PAUL This made for a much harder landing. RACHEL In order to protect their cosmonaut, Yuri was ejected out of the capsule as it neared the ground. PAUL That allowed Yuri to land softly on his own parachute and separate from his capsule. RACHEL Because of his propaganda importance to the Soviet Union, Yuri was never allowed to travel back into space. PAUL The moon takes it time approaching the eastern horizon starting on the 14th. RACHEL That’s because its approach to the sun is very shallow. PAUL This always happens during the spring. RACHEL Contrast this to the autumn when the moon’s approach to the horizon more vertical. PAUL So as a consequence, you have more opportunities to observe Earthshine during spring mornings. RACHEL Look for the moon in the low east-southeast as you drive to work. PAUL Earthshine will appear on the right side of the moon. RACHEL That’s Idaho Skies for the third week of April. Next week marks the end of our drought of meteor showers. PAUL Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com. For Idaho Skies this is Paul... RACHEL ...and Rachel. PAUL Dark skies and bright stars.

Monday, April 6, 2015

Merak is this Month's Star

This month look for the star Merak in Ursa Major. The popular name of Ursa Major is the Big Dipper. Actually, the Big Dipper is an asterism, or familiar pattern of stars and not a constellation. The Big Dipper asterism represents a bear’s hind quarters and extremely long tail. The rest of the bear consists of fainter stars, which gives Ursa Major its ursine shape. The constellation’s name means Great Bear in Latin.

Astronomers call Merak Beta Ursae Majoris. In Arabic, Merak means “flank of the bear”. Merak is a star larger star than our sun; it’s three times more massive and 60 times brighter. Its extra mass squeezes the star’s core with such great force that it’s fusing its hydrogen fuel faster than does the sun. Merak’s greater fusion rate makes it a white hot star with a surface temperature of over 15,000 degrees. Merak is 79 light years away, so the light you see tonight left the star in 1936.

You’ll find Merak and Ursa Major high overhead after it gets dark in April. The dipper is upside down and appears to be pouring the water in its bowl into the Little Dipper.

Transcript for April 5 - 11

PAUL
Welcome to Idaho Skies for the second week of April. We’re your hosts, Paul...

RACHEL
...and Rachel.

PAUL
Looking for Saturn?

RACHEL
Then look no further than the moon on the morning of the 8th.

PAUL
Saturn is the cream-colored star below the moon.

RACHEL
Saturn shows its rings through a small telescope or spotting scope.

PAUL
But not in most binoculars.

RACHEL
A magnification of as little as 25 power is enough to see its rings and brightest satellite, Titan.

PAUL
In a telescope, Titan will appear as the star to the upper right of Saturn.

RACHEL
Titan is a wonderful satellite by itself.

PAUL
It’s 50% larger than Earth’s moon.

RACHEL
And it has an atmosphere 50% greater than Earth’s atmosphere.

PAUL
Below its icy surface may be a deep liquid ocean.

RACHEL
Jupiter is approaching the Beehive star cluster because it’s retrograding.

PAUL
Retrograding? What’s that, some kind of 70’s fashion?

RACHEL
Retrograde motion occurs when Earth’s motion begins to overtake the orbital motion of a more distant planet like Jupiter.

PAUL
So during retrograde, outer planets travel from east to west across the sky, rather then the normal west to east.

RACHEL
On the evening of the 8th, Jupiter reaches the end of its retrograde motion and is at its closest to the Beehive star cluster.

PAUL
The pair is so close together that you can see both at the same time in binoculars.

RACHEL
If you point your binoculars at Jupiter on the 8th, place it on the left edge of your binocular’s view.

PAUL
That way the Beehive star cluster will pop out on the right side.

RACHEL
Then take a closer look at Jupiter to see largest satellite, Ganymede on the right side of Jupiter.

PAUL
When you see Ganymede, you’re looking at the largest satellite in the solar system.

RACHEL
It’s a giant moon that’s larger than the planet Mercury.

PAUL
And as the Hubble Space Telescope recently discovered, it most likely contains a vast ocean beneath its icy exterior.

RACHEL
In fact, there may be more liquid water beneath Ganymede than on Earth.

PAUL
Venus is climbing higher above the horizon every night while the Pleiades star cluster is descending lower.

RACHEL
The two meet up on the evenings of the 10th and 11th when they will be less than three degrees apart

PAUL
That puts them so close together that you can enjoy both at the same time in a pair of binoculars.

RACHEL
The Pleiades are located to the upper right of Venus.

PAUL
Look for the pair in the low west at around 9:30 PM.

RACHEL
You won’t be able to miss brilliant Venus.

PAUL
That’s Idaho Skies for the second week of April. Next week we celebrate a space-age anniversary that took place 54 years ago.

RACHEL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com. For Idaho Skies this is Rachel...

PAUL
...and Paul.

RACHEL
Dark skies and bright stars.

Monday, March 30, 2015

Transcript for Mar 29 to April 4

RACHEL
Welcome to Idaho Skies for the first week of April. We’re your hosts, Rachel...

PAUL
...and Paul.

RACHEL
The moon and Jupiter form a compact triangle with the Beehive star cluster on March 29th.

PAUL
Therefore, if you didn’t get a chance to find this beautiful star earlier this month, here’s your next chance.

RACHEL
The moon, Jupiter, and the Beehive will nearly fit together within your binoculars.

PAUL
You can’t miss the Beehive; it will be the tight grouping of stars located in the upper right edge of your binoculars.

RACHEL
The bright star beneath the moon on the evening of the 4th is the 15th brightest star in the sky.

PAUL
The reason Spica appears as the 15th brightest star is that it’s ten times more massive than the sun.

RACHEL
Its extra mass increase its fusion rate to furious levels.

PAUL
And that makes Spica shine over 12,000 brighter than the sun.

RACHEL
Unfortunately, candles that burn bright like Spica also live fast.

PAUL
One day Spica will end its life in a supernovae explosion.

RACHEL
So if you think Spica’s bright now, then wait another few million years when it dies.

PAUL
Millions of years is very short in stellar years.

RACHEL
Closer to Earth, Idaho gets to see a total lunar eclipse on the 4th.

PAUL
You’ll need to go outside after 2:30 AM to see the beginning of the eclipse.

RACHEL
The eclipse reaches it maximum extend across the moon by the time morning twilight begins at 5:00AM.

PAUL
Fortunately, the 4th is a Saturday morning.

RACHEL
So you won’t have to miss out on sleep prior to going to work.

PAUL
You can expect the moon to turn red during the eclipse.

RACHEL
How red depends on the clarity of Earth’s overall atmosphere.

PAUL
This means the moon could range from bright light orange...

RACHEL
...to a dull, dark red.

PAUL
Try taking a picture of the eclipsed moon.

RACHEL
A camera with an optical magnification of six power will be sufficient.

PAUL
Just be sure to place your camera on a tripod for stability.

RACHEL
That way it won’t shake around during the exposure.

PAUL
Which you should experiment with.

RACHEL
Try exposures all the ways up to a second or two long.

PAUL
That’s Idaho Skies for the first week of April. Next week is an auspicious time to observe the planets.

RACHEL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps.
For Idaho Skies this is Rachel...

PAUL
...and Paul.

RACHEL
Dark skies and bright stars.

Monday, March 23, 2015

Transcript for March 22 - 28

PAUL
Welcome to Idaho Skies for the last week of March. We’re your hosts, Paul...

RACHEL
...and Rachel.

PAUL
The moon passes close to Venus on the 22nd.

RACHEL
Look for this attractive pairing of the crescent moon and brilliant Venus.

PAUL
You’ll also see Earthshine through your binoculars.

RACHEL
That old moon really knows how to pose.

PAUL
On the 24th, it’s immersed in the Hyades star cluster.

RACHEL
The view should be quite nice through binoculars, with the thin crescent moon surrounded by a multitude of stars.

PAUL
It may not seem that way, but the Hyades star cluster spans an area much larger than the moon.

RACHEL
This will really be apparent when you see them together on the 24th.

PAUL
Since the moon is still a crescent, it should be easy to photograph it and the Hyades through a camera using its optical zoom.

RACHEL
A magnification as little as six power should be enough.

PAUL
Be sure to use a tripod for the camera since you’ll need an exposure several seconds long.

RACHEL
Orion the Hunter is arguably the most recognized constellation after the Big Dipper.

PAUL
Although the Big Dipper is only part of the constellation of Ursa Major the Big Bear.

RACHEL
You’ll find Orion just below the moon on the night of the 25th.

PAUL
If you have binoculars, then direct your attention to Orion’s belt.

RACHEL
His belt is the line of three stars crossing in the middle of the constellation.

PAUL
Hanging down from the middle star is a shorter line of stars that form his sword.

RACHEL
This is really where you should pointing your binoculars or small telescope.

PAUL
You’ll see a bright cloud in the middle of Orion’s sword called the great Orion Nebula.

RACHEL
This is a large cloud of glowing gas and dust in the process of giving birth to thousands of stars.

PAUL
In binoculars, it appears as a white cloud.

RACHEL
In a small telescope, the cloud is sprinkled with a few stars.

PAUL
In a larger telescope, the cloud turns light green from glowing oxygen gas.

RACHEL
Even though its hydrogen gas emits more light than oxygen, our eyes are more sensitive to the green light of oxygen than the red light of hydrogen.

PAUL
So the Orion nebula never appears red to our eyes.

RACHEL
The moon is located at the feet of Gemini the Twins on the 26th.

PAUL
In really dark skies, you might notice a faint and fuzzy spot located above the moon and on the other side of Gemini’s left foot.

RACHEL
This is the star cluster M-35.

PAUL
To see the cluster, aim your binoculars at the moon and scan straight up along the moon’s terminator.

RACHEL
You’ll soon run into the M-35 star cluster.

PAUL
In binoculars, it appears like a fuzzy cloud.

RACHEL
However, you should notice several stars immersed in the cloud if viewed from dark skies.

PAUL
The moon and Jupiter forms a compact triangle with the Beehive star cluster on the 29th.

RACHEL
Therefore, if you didn’t get a chance to see this beautiful star cluster on the 2nd, here’s your next chance.

PAUL
The three of them will just about fit within your binoculars at the same time.

RACHEL
And the Beehive will occupy the upper right edge.

PAUL
That’s Idaho Skies for the last week of March. Join us next month for the space and astronomy events for Idaho.

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

For Idaho Skies this is Rachel...

PAUL
...and Paul.

RACHEL
Dark skies and bright stars.

Tuesday, March 17, 2015

Transcript for March 15th to 21st

RACHEL
Welcome to Idaho Skies for the third week of March. We’re your hosts, Rachel...

PAUL
...and Paul.

RACHEL
The moon is new on the 20th.

PAUL
That means beginning the morning of the 16th you should start looking for Earthshine as you drive to work.

RACHEL
Earthshine is that faint illumination on the dark portion of the moon from sunlight reflected off of Earth.

PAUL
Earthshine can be so bright that through binoculars, that you can make out the lunar seas on the dark portion of the moon.

RACHEL
What a sight an astronaut would see standing on the moon during Earthshine.

PAUL
Earth would be four times larger than the moon appears to us.

RACHEL
And it would be about 16 times brighter.

PAUL
An astronaut would see blue oceans...

RACHEL
...white clouds and polar caps.

PAUL
Even some land masses would be visible.

RACHEL
Hey, spring begins on the 20th at 3:45 PM.

PAUL
That’s when the sun passes right over Earth’s equator.

RACHEL
For the last six months, the sun has been located overhead for locations south of the equator.

PAUL
Now it’s our turn for longer days, shorter nights, and warmer weather.

RACHEL
However, please remember that Earth’s distance from the sun has nothing to do with the seasons.

PAUL
In fact, Earth’s actually closer to the sun on January 4th when Idaho is very cold.

RACHEL
The seasons result from the tilt of Earth’s axis of rotation relative to the plane of its orbit around the sun.

PAUL
During the winter, the Northern hemisphere points away from the sun.

RACHEL
This creates shorter days and longer nights.

PAUL
And the sun crosses the sky at a lower altitude above the horizon.

RACHEL
The combinations of low sun angle and fewer daylight hours makes the Northern hemisphere get very cold.

PAUL
The moon reappears in the evening low in the western sky on the 21st.

RACHEL
Point you binoculars at Mars, the most noticeable star to the lower right of Venus.

PAUL
You’ll see that Mars is keeping close quarters with the moon.

RACHEL
And be sure to look for Earthshine on the left side of the moon.

PAUL
That’s Idaho Skies for the third week of March. It’s star cluster week next week.

RACHEL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps.
For Idaho Skies this is Rachel...

PAUL
...and Paul.

RACHEL
Dark skies and bright stars.