Welcome to Idaho Skies for the third week of April. We’re your hosts, Rachel...
PAUL
...and Paul.
RACHEL
There are some great astronomical opportunities this week.
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To begin with, Earth passes its closest to Mars on the 14th.
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That night bright orange Mars appears above the full moon.
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The moon is full on the night of the 14th and morning of the 15th.
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Many Americans name April’s full moon the Egg Moon.
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However, this year’s Egg Moon is a bit different from usual
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That’s because it turns a shade of orange, like nearby Mars.
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This month’s lunar eclipse begins around 11:30 PM on the 14th.
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That’s when a darkening should appear on the left edge of the moon.
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The moon will continue drifting deeper into Earth’s shadow over the next hour and 45 minutes.
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By then, the moon will glow somewhere between a deep red and a light orange.
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Wait. If the moon is passing though Earth’s shadow, why is glowing at all?
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Well, Earth does block direct light from the sun, but Earth’s atmosphere bends and refracts red light from the sun.
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This refraction results in the moon’s illumination by all of the sunsets occurring along the rim of Earth.
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The exact shade of the moon depends on the clarity of Earth’s atmosphere at the time of the eclipse.
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You can continue to observe the eclipse until 4:00 AM on the morning of the 15th.
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Try recording the eclipse with your digital camera.
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You’ll need to attach your camera to a tripod in order to keep the camera motionless long enough for the exposure.
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Set the camera’s optical zoom to its maximum magnification and manually focus the camera on infinity.
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Record several images in a row and vary the shutter speed each time.
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The bright double star, Zubenelgenubi appears to the moon’s left on the night of the 15th and morning of the 16th.
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Zubenelgenubi is the star to the moon’s lower left.
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Saturn is the brighter star and farther away to the moon’s left.
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Your binoculars show that Zubenelgenubi is actually a pair stars.
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On the morning of the 17th, Saturn is just above the moon.
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It will be very close, just twice the moon’s apparent diameter away.
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A small telescope shows Saturn’s rings and you don’t need very much magnification.
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Yep. Just 25 power is enough to begin seeing the rings.
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That’s Idaho Skies for the third week of April. Next week we’ll be observing the Lyrid meteor shower and Venus.
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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.
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