The birthday of a giant and a giant lunar coverup
Feb. 15 would have been the great Galileo Galilei’s 456th birthday. Without a doubt, he was one of the great cornerstones of the foundation of modern-day astronomy. There were indeed others before him, including Nicolaus Copernicus, who came up with the theory that the planets, including our Earth, revolved around the sun and not the other way around.
Many people think Galileo invented the first telescope, but it was Hans Lippershey, a German-Dutch glassmaker who came up with the first ‘scope in the early 1600s. A few years later Galileo found out about this new invention, and within a day or so he built his very own telescope and went to work turning conventional celestial thinking upside down.
When Galileo directed his telescope toward the moon he saw mountain chains and valleys and remarked how there are many similarities between the face of the moon and the face of Earth. Most people in his time assumed the moon had to be a perfectly smooth sphere since it was part of the heavens. Among his many other observations, Galileo observed little “stars” revolving around Jupiter and concluded they were moons of Jupiter and computed their orbital times. He also found that the planet Venus goes through phases or shape changes like our moon. Galileo considered these two observations, and others, as proof that Copernicus was right. The Earth was not the center of the known universe at that time, but rather the sun.
Galileo’s finding and claims got him into a lot of trouble. The Roman Catholic Church at the time put him on trial and eventually convicted him of a form of heresy. He was placed under house arrest for the rest of his life, but even during that time he continued his work on theories involving gravity, motion, and mathematics. Eventually, after 350 years, Galileo was officially pardoned by Pope John Paul ll in 1992
One of the biggest thrills of my life was actually seeing one of Galileo’s telescopes on display at the Galileo Museum in Florence, Italy. I so wanted to pick it up, but the highly elaborate security system in the museum prevented that. It was still a religious experience for me!
I wouldn’t call this a religious experience, but this coming Tuesday morning, weather permitting, you could observe something really cool and out of the ordinary. The waning crescent moon will pass directly in front of the planet Mars in the low southeast sky during morning twilight. You can easily watch Mars disappear behind the moon with a small telescope or even a pair of binoculars.
The moon and the planets, including our own Earth, all orbit around the sun in nearly the same mathematical plane but at different speeds. The result is that our fellow planets and the moon can only be found within a relatively narrow band in our sky that stretches across the entire celestial sphere. This is called the zodiac band. Because of their different speeds in their orbits around the sun, individual planets move amongst each other within the zodiac band, and at times can draw fairly close to each other. When this happens it’s called a conjunction, or what I like to call “a celestial hugging.” Since the moon is not only orbiting the sun once a year, but also the Earth every 27.3 days, it hurries through the entire celestial sphere every month, frequently having close encounters with the planets in our night sky.
Every once in a while, the moon will cross directly in front of a planet from our view on Earth. This is called an occultation. That’s what’s happening with the moon and Mars this coming Tuesday morning.
In southwestern Minnesota, the thin crescent moon will move eastward in front of Mars at approximately 6 a.m. Mars will appear as a moderately bright star with a definite reddish hue. Start observing Mars with a telescope or binoculars around 5:30, and as 6 approaches, you’ll see the moon get closer and closer to the red planet. A few minutes after 6, Mars will disappear as it slips behind the lower left portion of the moon’s crescent-shaped disk.
A little after 7:20 a.m. Mars will emerge from behind the moon, but unfortunately by then the sun will have already risen and Mars will be lost visually in the daylight glare. Don’t attempt to look for Mars when it emerges from behind the moon with binoculars or a telescope. The sun will be very close by in the sky and you could permanently damage your eyes. It could even cause blindness if you accidentally pointed your scope at the sun.
On Wednesday morning, Feb. 19, a thinner waning crescent moon will be in a really close conjunction with the bright planet Jupiter in the very low southeast sky in the morning twilight. The moon will be just to the right of the Jupiter.
To top it off this week, in the early morning twilight on Friday, Feb. 20, the extremely skinny crescent moon will be hanging just to the lower right of Saturn in the very, very low southeastern sky near the horizon. This will definitely be more of a challenge to see, but well worth the effort!
Unfortunately, because the planets in these conjunctions are so low in the sky, they will appear super fuzzy through a telescope because of the thicker layer of the Earth’s atmosphere. It’ll still be a great show though!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul.