Easter, one day when we all can admit need for forgiveness
Editor’s note: This is the last of a series on astronomy.
The adviser to this series on astronomy, Dan Fleisch, says that if he hadn’t studied and taught physics, he might have taken up history.
Now a professor emeritus, he was a full time professor at Wittenberg University in 2011 when he explored a piece of physics and religious history while leading a summer tour for students.
“In Galileo’s Footsteps,” he stopped at Italian museums and cultural sites any college teacher would feel derelict for not exposing his students to — experiences Fleisch strengthened by taking along someone well versed in of European art history.
But the astronomy highlight — and the place where Fleisch did most of the talking — was Rome’s Basilica Santa Maria degli Angeli, a cathedral that doubles as an astronomical observatory.
It is not alone. Like Paris’s Saint-sulpice Church and Balogna, Italy’s Basilica of San Patronio, it features a pinhole high in the structure that allows a beam sunlight to enter from the south and fall on a meridian (longitude) line marked on the floor.
Throughout the year, the beam travels the length of the line, making it possible to identify the dates of the summer and winter solstices and spring and fall equinoxes, on which light and darkness split the day evenly.
And that’s particularly important to note today because Easter, in Western Catholic and Protestant churches, is celebrated the first after the first full moon of the spring equinox.
Back to the future
The website of the still existing Vatican Observatory in Rome says
“the first foreshadowing” of the church’s work in astronomy “can be traced to the constitution by Pope Gregory XIII of a committee to study the scientific data and implications involved in the reform of the calendar which occurred in 1582.”
But the story, so far as today and every Easter is concerned — goes back farther to the year 325, the First Council of Nicea and a turning point in the Roman Empire.
Nicea is located just outside Constantinople, which was named for the Emporer Constantine, who called the council in an effort to reunite the empires Eastern and Western remnants.
The emperor, who converted to Christianity shortly before his death, is remembered for embracing members of the faith that Romans had previously beheaded. Nor is there dispute that Roman functionaries oversaw and carried out
Jesus’ crucifiction.
At Nicea, the church’s Eastern and Western factions agreed to condemn as heresy Arius of Alexander’s claim that the crucified Jesus was not divine but of a different order from God. It was a crucial step in establishing the Trinity of Father, Son and Holy Spirit in the Christian tradition. And Constantine saw it as a step toward unity.
He failed, however, in his attempt at what might seem a more easily achievable goal: Getting the two sides to celebrating Easter — the most important date on the Christian liturgical — on the same day. To this day, both calculate the day by their own calendars, with Orthodox churches preparing to celebrate next on Sunday, May 5.
But the online Greek Reporter says that after next year, when the celebrations coincide, the gap between them will begin to widen “for purely astronomical reasons” and “from 2700 onward … will never coincide again.”
The Sun God and the calendar
Frustrated with a dysfunctional calendar that tried to take its signals from the moon and sun, Julius Caesar took a giant step for person kind in 46 BCE when he went 100% solar.
Based on an Egyptian model developed in the region that once worshipped the Sun god Ra, it set the length of each year at 365.25 solar days and, like the modern calendar, threw in a leap day every fourth year.
Clearly an improvement, it was still, from the outset, like a watch than ran 11 hours and change faster every day, pushing the calendar ahead of the seasons. By mid 1500s, the calendar was running about 10 days ahead, which messed up the calculations for, among other things, Easter.
So in 1582 — a mere 20 years after the Council of Trent asked him to — Pope Gregory XIII closed the tap by tearing the pages for Oct. 5 -14 from the 1582 calendar.
So that a future Pope wouldn’t have to face the wrath of parishioners unable October birthdays, Gregory also ordered his mathematicians to lightly cook the books on the Julian calendar. They did so: by shaving the leap days from all century years (years ending with two zeros) except those evenly divisible by 400.
The Gregorian calendar is now in sync enough to run smoothly not for 20,000 miles but for 20,000 years. And after that fine bit of work by the staff, the Vatican decided to invest a little money in more closely following the workings of the sun with those catheral observatories.
The Centric Choices: Geo or Helio?
Europe was about in the middle of its cultural Renaissance by the time the calendar named for a pope was supplanted by one named for a caesar. And changes were afoot in thinking about what powered the solar system as well.
Even before Gregory to the calenda, Nicolaus Copernicus (1453-1543), a polymath figure from Poland, advanced the idea that that the sun, not the earth, was the point around which all the planets traveled. It’s called the heliocentric model.
In doing so, he discarded an article of faith that had ruled cosmology since before the time of Aristotle. Born 28 years after Copernicus’s time was up, German astronomer Johannes Kepler shredded a second article of cosmological faith: That the planets traveled in circles, shapes thought to express the perfection of the unchanging.
Kepler replaced them with the ellipse, which many today know from the workings of elliptical trainers.
Both of those assumptions, as it turned out, violated the same article of religious faith articulated in Psalm 104, Verse 5 of the Holy Bible: “God fixed the Earth upon its foundation, not to be moved forever.”
And certainly not around the sun.
Corrective lenses
The most often cited date for the invention of the telescope is 1608, with credit due to the Dutch eyeglass maker, Hans Lippershey – well, him and an international Dutch marine merchant fleet that was sailing the seas and needed to see farther ahead.
Two years after the Dutch invention, an Italian mathematician and tech wonk named Galileo Galilei made improvements on the telescope in his home workshop and got at look at the night sky under higher magnification.
He saw the moons of Jupiter were orbiting Jupiter,
which meant not everything was orbiting the Earth, which then could not be the center of all things.
He saw Venus seemed to change sizes and shapes ( from circular to crescent) in a way it would not if it orbited earth.
Galileo also saw spots on the sun and craters on the moon, evidence that the heavens were not as perfect as they’d been portrayed.
The result was not a different world view or even solar system view. It was a different cosmology revolution unwelcome not only by a Catholic Church already occupied with the revolt of Protestants during the Protestant Reformation. And those selfstyled religious reformers, evangelizing for their own cause, had no more interest in cosmological reform than Pope, Uvban VIII.
That the pope was a friend of Galileo is just one twist in a complex story of Galileo’s trial and confinement, rather than execution, for the last 40 years of his life.
While that’s largely a story for another day, Fleisch is convinced the church astronomers by then were skilled and observant enough to have realized “Kepler had it right” about heliocentrism.
The evidence, he said, “is overwhelming.”
But he adds that “We shouldn’t feel too superior to the people who were trying to figure this out” because a telescope focused at the past would also show us that:
Copernicus was right about the centrality of the sun but wrong about the shape; Kepler was right about the shape of orbits but wrong about the number of planets.
And Galileo, while right about the movement of the earth, also advanced a much ridiculed theory that ocean tides were caused not by the moon’s gravitational pull but a general sloshing of water caused by the earth’s rotation.
When Pope John Paul acknowledged in 1992 that Galileo had been mistreated by church, he defended those involved as being of good faith but “incapable of dissociating (their) faith from an ageold cosmology” unseated by new technology.
Whatever final judgments might be made, Easter seems a day on which we all might acknowledge the need for forgiveness in a world in which we all wrong one another.