Friday, October 31, 2014

This month look for the star Caph in the constellation Cassiopeia. Caph is called Beta Cassiopeiae by astronomers. And as you would guess from its name, Caph is the second brightest star in the constellation.

Cassiopeia may have originated as the Greek goddess, Hecate, but was later transformed into the queen of Ethiopia. According to the Greek legend, Cassiopeia boasted she was more beautiful than the Nereids. The unhappy Nereids complained about this slight to their father, the god of the sea. As punishment, Poseidon sent the sea monster Cetus to destroy Cassiopeia’s coastlands. King Cepheus and queen Cassiopeia learned they could halt the destruction of their lands only if they offered their daughter, Andromeda to the sea monster. So unfortunate Andromeda was chained to the rocks to await the next arrival of Cetus. Fortunately, before the sea monster arrived, Perseus, who was traveling back home on his flying sandals, saw and rescued Andromeda.  

The star Caph is 54 light years away. Therefore, if you were born in 1960, Caph is your birthday star this year. The surface of Caph is 1,600 degrees Fahrenheit hotter than our sun. It’s also four times larger and 28 times brighter. Caph is old enough that the energy from hydrogen fusion can’t preventing its core from contracting. The core is shrinking as a result and growing hotter. Eventually the contraction will warm the core up to the point that helium fusion will begin. Once its helium begins to "burn", Caph will expand in size and change into a cooler giant star.

Transcript for November 2 - 8

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

RACHEL
...and Rachel.

PAUL
The Taurid meteor shower peaks on the morning of the 3rd.

RACHEL
Meteor showers occur when Earth’s orbit intersects the orbit of a comet.

PAUL
The dust ejected from a comet continues to orbit the sun until it slams into Earth’s atmosphere, at speeds ranging from 7 to 70 miles per second.

RACHEL
At a speed of 70 miles per second, a cometary dust particle could cross Idaho from west to east in about six seconds.

PAUL
The hyper-velocity of a reentering dust particle violently compresses the air ahead of it.

RACHEL
This creates a shock wave that heats the air to thousands of degrees.

PAUL
The hot shock wave ahead roasts and melts the reentering dust particle.

RACHEL
Most meteors are vaporizing about 70 miles above Earth’s surface.

PAUL
And most are no larger than a grain of sand.

RACHEL
Unfortunately, for the Taurid meteor shower this year the moon is in a waxing gibbous phase.

PAUL
That means the moon is a nearly full and won’t set until 3:30 AM.

RACHEL
So if you want to observe this shower, you’ll need to wait until after 3:30, when the moon has finally set.

PAUL
By that time, meteors from this shower will appear to originate from overhead.

RACHEL
The Taurids don’t sound like a very promising meteor shower when you consider that you might only see five meteors per hour from this shower.

PAUL
However, the Taurids have several tricks up their sleeve.

RACHEL
Yep. First, the stream of meteoroids forming this shower is massive and spread out.

PAUL
So you can observe meteors from this stream for several weeks around the day of peak intensity.

RACHEL
And second, the rocky material making up the meteoroids tend to be larger, even pebble size.

PAUL
Therefore, Taurid meteoroids can create very bright meteors over several weeks as they reenter Earth’s atmosphere.

RACHEL
The moon appears around two large galactic star clusters on the evening of the 7th and 8th.

PAUL
After it gets dark on the 7th, sweep the region above and below the moon with your binoculars.

RACHEL
You’ll see the Pleiades star cluster above the moon and the Hyades star clusters below.

PAUL
If you miss them or the weather is bad on the 7th, the star clusters will be located above the moon on the 8th.

RACHEL
That’s Idaho Skies for the first week of November. Next week we’ll tell you how to find and observe the Orion Nebula.

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

For Idaho Skies this is Paul...

RACHEL
...and Rachel.

PAUL
Dark skies and bright stars.