PAUL
Welcome to Idaho Skies for April 1st and 2nd. We’re your hosts, Paul...
RACHEL
...and Rachel.
PAUL
Hey early-risers, look for the Morning Star this week.
RACHEL
On the morning of the 1st, Venus appears to the left of the very thin crescent moon. On the morning of the 2nd, Venus will appear on the other side of an even thinner moon. However, the moon will be so thin that you might not see it in morning twilight at 6:00 AM. You might try using your binoculars, but not if the sun has already risen.
PAUL
Venus is the very bright star in the low east-southeast. It appears so bright for two reasons. First, Venus is very close to the sun. At an average distance of 67 million miles, Venus is only 2/3rds of Earth’s distance from the sun. This means that sunlight is 225% more intense at Venus than it is at Earth. That more intense sunlight makes Venus appear as the brightest star in the sky.
RACHEL
The second reason that Venus appears so bright is that its clouds reflect more of the sunlight shining on them. Earth reflects 30% of the sunlight shining on it while Venus reflects 75%. Since the
diameters of Venus and Earth are nearly identical, size is not a factor in either planet’s brightness. Combining these two factors, distance and reflectivity makes Venus 5.5 times brighter than Earth.
PAUL
Those bright clouds are hiding a secret. Beneath them, the atmosphere of Venus reaches temperatures of 900 degrees Fahrenheit and air pressures 90 times greater than our own. This hot and dense atmosphere is also laden with sulfuric acid. With all these nasty conditions, sunlight still manages to reach the surface of Venus. Automated Russian landers have discovered that its surface is as brightly illuminated as Earth during a thunderstorm.
RACHEL
That’s Idaho Skies for the 1st and 2nd of April.
PAUL
Be sure to follow us on Twitter @IdahoSkies 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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