Calendar offers hints of spring

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Fat Tuesday and Ash Wednesday mark the start of Lent, heading toward spring which is now just over 4 weeks away. Yesterday was Galileo’s Birth Anniversary; Copernicus was born 4 days later but 90 years earlier. John Glenn’s historic orbital flight occurred 55 years ago this Friday.


February 16, 2015

 

[Dave Heller] Events on the calendar this week point the way to spring 2015. Let’s look ahead with Derrick Pitts, chief astronomer at the Franklin Institute. And Derrick, we need look no further than tomorrow.

[Derrick Pitts] Indeed you’re right, because tomorrow happens to be a very special day. If you’re on the religious side of things, it’s called Shrove Tuesday. If you’re on the party side of things, it’s Mardi Gras–

Mardi Gras!

Mardi Gras! Or, Fat Tuesday.

  • Revelers cheer for beads though clouds of theatrical smoke from a float during the Krewe of Proteus Mardi Gras parade in New Orleans, Monday, Feb. 16, 2015. The day is known as Lundi Gras, the day before Mardi Gras. (AP Photo/Gerald Herbert)

The period of Lent is linked to the lunar cycle.

As is the time at which we celebrate Easter, so the easiest way to think of it is that Easter is the first Sunday after the first full moon after the Vernal Equinox.

Tuesday, Wednesday … Friday is also a day of note.

It is a very special day, indeed, because it’s the 55th anniversary of John Glenn’s orbital flight around the Earth. He made three orbits of the planet which was the first orbital flight of an American. And his flight came right on the heels of two other sub-orbital flights, and Yuri Gagarin’s historic flight by the Russians before that. So, this was a very, very busy time in the early history of space exploration, and of course we still remember that day because it had such a significant effect of getting our engines really started to begin our assault, if you will, on the moon.

What’s old may be new again when those 15-20 minute flights become available to the public at large in years to come.

Yeah, that’s a really interesting point because it shouldn’t be too long from now that the first purveyor of the, sort of, vacation trip to space Richard Branson and his company Virgin Galactic will begin their flights, allowing regular people to really get a feel for what it’s like to be truly weightless and to see the Earth from that incredible vantage point of Earth orbit. Now, they only have to go up 62 miles. That’s the arbitrary boundary that’s been identified as the Earth’s atmosphere and space. I believe the flight plan for the Virgin Galactic trips is really not that much more than just an hour and a half or so because it will not take long to get up to the altitude of about 50,000 feet where they’ll actually begin the boost up to space, and then it’s just another few minutes up to that region of about 62 miles. They’ll sort of roll the craft over and begin the descent back to Earth where the craft will land just like an airplane, on a runway.

Anniversaries and even birthdays of note this week.

Yesterday, Sunday, was Galileo’s birth anniversary. He was a great guy, wasn’t he? He was born in 1564, but Galileo’s work was prefaced by Copernicus who was born four days later than Galileo, but 90 years earlier. So Nicolaus Copernicus had the idea of what the structure of the solar system really must be with the sun in the center and the other planets orbiting around. Of course, he was restricted by religious doctrine at the time that forbade him from saying that this is the way it is. He could only suggest this as a possibility. What Galileo did with his work with the telescope was to actually make an observation that supported Copernicus’ theory that the solar system was structured this way. What he saw was the moons of Jupiter, the four largest moons of Jupiter, orbiting Jupiter. And that triggered for him the real identification that here’s the model for how our solar system actually works.

Was it then therefore thought though that the sun was the center of the universe?

Well for all intensive purposes, yes, the sun was considered to be the center of the universe, although there wasn’t any clear understanding that our sun, our star, along with all the other stars that were visible in the sky were part of an item called a galaxy. All of it was known as “the heavens” at that time, but there was no understanding of anything beyond our solar system of just the visible planets — Mercury, Venus, Mars, Jupiter, Saturn.

  • Etching of Astronomer, Galileo Galilei is seen in an undated photo. (AP Photo)

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