Transcript: 20 - 26 June

PAUL
Welcome to Idaho Skies on Radio Boise. This is the third week of June. We’re your hosts, Paul..

RACHEL
..Rachel..

KRIS
..And Kris

PAUL
Summer begins this week.

RACHEL
Because the spin axis of earth is tipped relative to its orbit around the sun, we experience seasons.

KRIS
So earth is not spinning upright. Instead its spinning slightly tipped over on its side.

PAUL
In fact it’s tipped about twenty-three and a half degrees.

RACHEL
The northern hemisphere’s summer begins at the time when the North Pole is tipped its greatest amount towards the sun.

KRIS
And this year that happens on the twenty-first at six twenty-six AM.

RACHEL
On the first day of summer the sun travels is highest distance above the horizon.

KRIS
This means the sun remains above the horizon for its greatest number of hours.

RACHEL
The high angle of the sun and the long day makes the summer our warmest time of the year.

KRIS
While it’s true that the earth orbits the sun in a slightly egg-shaped orbit, the changing distance between the sun and earth is not responsible for the summer.

PAUL
In fact, we’re at our greatest distance from the sun in early summer.

RACHEL
But meteorologists believe the earth’s elliptical orbit does have a subtle influence on the climate.

KRIS
Over tens of thousands of years the changing alignment between the earth’s spin axis and its elliptical orbit may influence the ice ages.

RACHEL
The amount of snow remaining over the summer appears to change as the earth’s elliptical orbit changes shape and orientation.

KRIS
And that may start an ice age.

PAUL
Have you seen Mercury? Your best chance occurs on the twenty-first.

RACHEL
Elusive little Mercury sets 90 minutes after the sun. But don’t expect it to be easy to see.

KRIS
That’s because it gets dark late in the summer and the path of Mercury across the sky is at its lowest angle.

RACHEL
So even though Mercury sets over an hour after the sun, it still won’t be very high above the horizon

KRIS
So try looking for Mercury at ten fifteen PM. That’s when it will be the brightest star very low in the west-northwest.

PAUL
By low, we mean less than the width of you palm when your arm is fully extended.

RACHEL
You should try using binoculars at first. Then after you locate the planet, use your eyes alone.

PAUL
There’s another star party at a national park this week.

KRIS
Between the twenty-first and twenty-fourth you can attend a star party at Bryce Canyon in southern Utah.

RACHEL
Bryce Canyon is located on the Aquarius Plateau. So the canyon has a high elevation and is far away from city lights.

PAUL
So you’ll experience some of our nation’s darkest skies at Bryce Canyon.

KRIS
Check out the Bryce Canyon website for more information.

RACHEL
That’s Idaho Skies for the third week of June. Next week we’ll discuss a Soviet space tragedy and aphelion. For Idaho Skies this is Rachel...

KRIS
..Kris..

PAUL
.. and Paul.

Transcript: 13 - 19 June

PAUL
Welcome to Idaho Skies on Radio Boise. This is the second week of June. We’re your hosts, Paul..

RACHEL
..Rachel..

KRIS
..And Kris

PAUL
In the sky this week you’ll find a attractive grouping between two planets and a star cluster.

RACHEL
The planets are Mars and Saturn.

KRIS
Mars is a small planet that’s only half the size of earth. Currently the rovers Spirit and Opportunity are exploring its surface.

RACHEL
Above the planet are the spacecraft Mars Odyssey, Mars Express, Mars Global Surveyor, and Mars Reconnaissance Observer.

PAUL
The skies above Mars are pretty crowded these days.

KRIS
Saturn on the other hand is the second largest planet in the solar system. Over nine earths would fit across its equator.

PAUL
Today the spacecraft Cassini is in orbit around Saturn. And on its largest moon, Titan, is the now defunct Huygens spacecraft.

RACHEL
On the night of the 17th Mars makes its closest approach to Saturn, from our perspective that is.

KRIS
They’ll appear only half a degree apart, or about the width of your thumb when you fully extend your arm.

RACHEL
With your binoculars you’ll see that the two planets have a neighbor.

KRIS
That’s right. It’s a sprinkle of stars that’s twice as wide as the moon.

RACHEL
We call that sprinkle the Beehive star cluster.

KRIS
And all three objects will easily fit within the field of view of your binoculars.

RACHEL
They’re close enough together that they may even fit within the field of view of your telescope, if you use your telescope’s lowest magnification.

KRIS
From meteorites, we know the planets in our solar system formed four point five billion years ago.

RACHEL
From measurements of the color and brightness of the stars in the Beehive, astronomers believe this cluster only formed 400 million years ago.

PAUL
In other words the cluster is less than one tenth as old as our solar system. That makes the Beehive literally a baby of our galaxy.

KRIS
The Beehive was known to the ancients. But since they didn’t have a telescope, they only saw it as a fuzzy cloud.

RACHEL
The first person to resolve the stars in the Beehive was Galileo in the year 1610.

KRIS
Galileo reported that he was astonished and delighted to see this small fuzzy cloud as a glittering cluster of stars.

RACHEL
While the planets appear close to the Beehive, they’re no where near each other.

KRIS
The light reflected from the planets them only 20 to 90 minutes ago.

RACHEL
And star light emitted by the Beehive star cluster left 500 years ago.

PAUL
Are you visiting the Grand Canyon this week?

RACHEL
If so, then be sure to spend some time at the Grand Canyon Star Party.

KRIS
Park rangers will direct you to the star party that takes place on the canyon rim from the 17th to 24th.

RACHEL
There will be so many telescopes there that you can spend hours observing planets, galaxies, nebulae, and star clusters.

PAUL
That’s Idaho Skies for the second week of June. Join us next week when we’ll talk about the first day of summer and our innermost planet, Mercury.

For Idaho Skies this is Paul.

RACHEL
..Rachel..

KRIS
.. and Kris.

Transcript: 6 - 12 June

PAUL
Welcome to Idaho Skies on Radio Boise. This is the first week of June. We’re your hosts, Paul..

RACHEL
..Rachel..

KRIS
..And Kris

PAUL
Spica, KBOs, and the moon, oh my!

RACHEL
Spica is the brightest star of Virgo, or its lucida.

KRIS
As far as the bright stars go, it’s not very bright. But the spring sky has more than its share of dim stars. So Spica really stands out in the low south-southwest.

RACHEL
On the evening of the sixth and morning of the seventh the moon passes very close to Spica.

PAUL
The closest approach that Idaho can see occurs shortly before they set.

KRIS
That’s when the pair will be just over one lunar diameter apart.

RACHEL
Look for the moon and Spica on the evening of the sixth and morning of the seventh. You’re best view will be through your binoculars.

KRIS
While they appear close together in the sky, they’re really very far apart. It takes light one and one half seconds to travel from the earth to the moon

RACHEL
…and 263 years to travel to Spica.

PAUL
Speaking of distant objects, Quaror (prounounced like Kwaa-waar) is at its closest to earth on the seventh.

KRIS
Quaror is a Kuiper Belt Object, or KBO. The KBOs form a belt on the outer edge of the solar system.

RACHEL
You can think of KBOs as icy asteroids in the solar system’s deep freeze. This makes them relics of the solar system’s origin.

PAUL
Okay, so the KBOs are distant, but just how distant?

KRIS
Quaror is a typical, if large, KBO. On the seventh it’s 3.9 billion miles away from the earth.

RACHEL
So a radio signal sent to explorers on Quaror would take 13 hours and 45 minutes to get there. That’s over half a day.

KRIS
Because of its great distance from the sun, a year on this giant snow ball lasts 286 earth years.

PAUL
If you stood on Quaror, the sun would appear as the brightest star in the sky.

RACHEL
But it would be a tiny and feeble point of light. The sun would be unable to melt the ice on Quaror’s surface.

KRIS
Did you know that astronomers recently discovered crystalline ice on the surface of this body?

RACHEL
Since the sun is unable to warm Quaror’s surface, there must be another source of energy on this giant comet to create the crystalline ice.

KRIS
Perhaps there are icy volcanoes or geysers erupting on Quaror.

RACHEL
In any event, we’ll learn more about the KBOs next decade when the New Horizons spacecraft visits Pluto and one or more KBOs.

PAUL
The moon is full on the eleventh.

KRIS
This month’s full moon is called the Rose Moon

RACHEL
While the full moon may be wonderful for romantic walks, it’s anything but romantic for astronomers.

KRIS
That’s because the light of the full moon brightly illuminates the night sky.

RACHEL
So the fainter stars we can see during other times of the month are washed out by the bright moonlight.

KRIS
That’s Idaho Skies for the first week of June. Join us next week when we’ll talk about a grouping between two planets and a bright star cluster.

For Idaho Skies this is Kris.

RACHEL
..Rachel..

PAUL
.. and Paul.