For this episode of Western Slope Skies, a look at the moons of Jupiter, and the two Galileos - the man and the machine.
In 1610, Galileo Galilei became the first person to observe another planet, Jupiter, and its 4 largest moons, Callisto, Europa, Ganymede, and Io. For the next 380 years, most scientists believed that those moons were similar to our Moon, that is, rocky spheres without activity or atmosphere.
Did you know that the Big Dipper is NOT a constellation? It’s actually an asterism - a pattern of stars in the sky, much like a pattern of clouds.
While there are many asterisms that are commonly known, none of them are constellations. Other fall and winter asterisms include the Little Dipper, the Winter Hexagon, and the Great Square of Pegasus.
The Big Dipper is part of the constellation, Ursa Major, the Great Bear. What most people see as the handle of the Big Dipper is the tail of the bear, while the bowl of the dipper is part of the body of the bear.
This is the third in a series on Women in Astronomy. Today, we meet Caroline Herschel.
Caroline Herschel was born in Hanover, Germany in 1750. Her early life was a conflict between her father, who wanted her to be educated in music and science, and her mother, who thought that household chores were the appropriate life for a woman.
In 1772, Caroline moved to England and joined her brother, William, who was already working in astronomy and music. Over time, they gradually left music and became full-time astronomers.
Early fall nights can be crisp, but it’s rewarding to go out after dark on these clear, moonless evenings to see some stars and constellations in our Western Slope skies.
Rising in the northeast just after dark, you will find a group of stars that looks like a “W” on its side. These stars are part of the constellation Cassiopeia, which commemorates a queen in Greek mythology.
The sun rises in the east each day in our western slope skies and appears to shine with constant brightness. However, we shouldn’t take the sun for granted, because the sun’s energy sustains most life on Earth. And, in this age of widespread, complex technology, the sun can impact our daily lives.
The sun, in fact, is not constant, and we need to pay attention to our active, local star.
Just about any clear night provides an invitation to go outside and see what’s up. Some nights, however, might offer a special attraction: a meteor shower; a conjunction between the Moon and a bright star or planet; or even a lunar eclipse. If you are a beginner stargazer you can maximize your sky watching efforts by taking a few simple steps.
Start with a star chart, and/or a Planisphere or a star-charting app that runs on a smart phone, tablet, or PC. These are valuable tools in learning the night sky, displaying any number of sky objects for any hour of the night.
As August began, all of the bright planets were visible in our western slope skies. Since all of our solar system planets orbit the sun, the visible planets change from night to night.
As of today’s program, we have already lost Mercury from view for the rest of this month. It was visible in the early dawn for the first two weeks of the month. However, we still have Venus shining low on the evening horizon. Saturn will end the month just a little higher than Venus. Jupiter rises well after midnight, followed by Mars even later.
The Perseid meteor shower sprinkles the night sky with shooting stars in August.
The meteors are bits of icy and rocky debris left behind by the Comet Swift-Tuttle, which was discovered in 1862. As Earth flies through the comet’s path, some bits of comet dust slam into the atmosphere at tens of thousands of miles per hour. They quickly vaporize, creating bright but brief streaks of light in the night sky.