Atlantis Dispatch 015:
in which ATLANTIS contemplates what a telescope really shows us…
Three maps of the cosmological systems: Ptolemy, Copernicus, Brahe. Courtesy: Library of Congress.
February 20, 2022
…begin transmission…
Atlantis spent the last few weeks polishing up the old monocular to best ensure safe voyage on our 2022 journey, back into the annals of science. The glinting glass of our scope reminded us how much reflection has contributed to our travels across Earth’s oceans and out into the InterPlanetary medium. During our little respite, a very impressive collection of mirrors, the James Webb Space Telescope (JWST), was successfully launched, all of its instruments successfully deployed, and now, JWST has reached her destination at Lagrange point 2 (aka L2). The location is key. Now that JWST is settled into L2, one million miles away from us, she’ll get sucked into Earth’s and the Sun’s gravitational pull, and maintain her solar orbit in tandem with ours, so that she can tell us all about the beautiful things she sees twice daily.
This puts Atlantis, our dear readers, and the rest of the world in a unique position to see the universe with unprecedented clarity, and will help us better understand how galaxies, like ours, form. Yes, little Jamesy with her solar array, antenna, sun shield, star trackers, and golden hexagonal mirrors will capture light waves coming at us from some of the oldest galaxies, so that we can see what was going on when those galactic light waves were first emitted.
Reader, by now you no doubt know how much Atlantis revels in the vast history of exploration, innovation, invention, and poetry. You also know how much we love a dialogue, so this next foray into the invention of the telescope, oft credited to Galileo, author of our favorite trialogue, should come as no surprise.
How does that simple machine of 412 years ago compare to the space telescopes we’re constructing today? Well, for starters, like all good art, it was arguably stolen. But for deeper considerations (for Atlantis prefers to sail in the deep end), “Galileo’s” telescope and his subsequent observations provided humanity with a new view and understanding of the universe.
Let’s start from the beginning.
In the decades before Galileo, the world was in a great tangle about the heavens. There were people of the old guard, like John Donne, who were really into the geo-centric world and who wrote poetry lamenting that altering the working model of the whole thing was just a terrible disaster. (In Donne’s wingéd words: “The sun is lost, and th’earth, and no man’s wit/ Can well direct him where to look for it.”) Along with Donne, there were the Ptolemaists who loved their epicycles and fixed stars more than the great globe itself.
And yet, in the astronomical froth, there was also Copernicus, who (more or less) quietly floated a new model of the heavens that looked like a set of concentric pancakes.
Then there was Tycho Brahe, that abducted little party animal who lost his nose in a duel over mathematics, feuded over astronomical questions, and eventually cooked up a combined model of the Ptolemaic and Copernican heavens, before he died at 54 from a urinary tract infection.
Meanwhile, in England, Thomas Digges got so excited by Copernicus’s diagram that he broke right through the sphere of the fixed stars and announced, in his version of the Copernican heavens, an infinite heavens instead. This new diagram, it turns out, made it possible for Hamlet to be bounded in a nutshell and count himself the king of infinite space, which brings us back to Denmark, and to the irresistible story of Tycho Brahe.
After installing a shiny silver tip to his face (not unlike the JWST’s secondary mirror) Tycho got to work with the tools he had at his disposal. The Danish king gave him a science island called Hven, complete with an observatory, where he started to collect Martian data with his astrolabes and sextants. He had some problems at first: the place was so windy that the instruments were unreliable, and his lab assistants didn’t have any fancy windshades to fix them, so they had to dig holes in the ground to look up at the sky. He overworked Hven’s residents, threw expensive parties on the King’s dime, and he gave his pet elk alcohol poisoning before he was finally exiled to Prague, where he died just eight years before Galileo got his hands on the “Danish Perspective Glass.”
Before Tycho attended his last party, however, and before he held his last pee, he took on a bright young scholar named Johannes Kepler, who later succeeded him as Imperial Mathematician to Rudolph II, inheriting the vast volume of planetary observations Brahe left behind.
Yet try as he might, Kepler simply could not plot Tycho’s terrifically accurate observations onto those Copernican pancakes (Copernicakes?). To this point, he had not theorized the elliptical orbit, and since all previous models relied on circularity, Kepler had to reinvent the model before he could see what might be going on with the motions of the planets.
At the time, the planets orbited around a giant known unknown: with the naked eye, no one could tell for sure whether the Copernican, or the Ptolemaic model accurately depicted the motions of the stars.
Enter Galileo and his telescope. It wasn’t exactly a, BAM!, Copernicus-wins-the-prize type of situation, but Galileo did smack astronomy with some crazy observations, including Jupiter’s moons (you know, the ones with water, where we are now looking for life), the craggy texture of the moon, and also the phases of Venus. His observations ultimately tipped the heavens against Ptolemy and Tycho, and quiet old Copernicus’s model won the day. The shift made it possible for the rest of the world to embrace what Kepler intuited: “in the center of the world is the Sun, heart of the universe, font of light, source of heat, origin of life and cosmic motion” (Kepler, J., Kepler’s conversation, [Note 16], 42, 45).
***
So back in the present, now that the sun has arrived in its proper place, what is Atlantis saying here in this historical revery? Well, what we’re saying is this: when you get a new telescope, the unknowns become knowable. But then, new unknowns begin to crop up, some of which inspire everlasting exploration, and entirely new ways of seeing.
Regarding the exploration part, Kepler totally gets it, and he gets it in a way that Atlantis loves. As he says in a letter to his BFF, Galileo,
…as soon as someone demonstrates the art of flying, settlers from our species of man will not be lacking. Who would have thought that the crossing of wide ocean was calmer, safer than of the narrow Adriatic Sea, the Baltic Sea, or English Channel? Given ships or sails adapted to the breeze of heaven, there will be those who do not shrink from that vast expanse. Therefore, for the sake of those who, as it were, will presently be on hand to attempt this voyage, let us establish the astronomy, Galileo, you of Jupiter, and me of the Moon.”
Hark, the sails of old Atlantis are adapted to the breeze of heaven, and we do not shrink from the vast expanse! So, when we are out there, what will we see, or perhaps more importantly, how will we see new things that are available to us?
Kepler is helpful here, too. Look at it this way. All of the models Kepler inherited were made of circular orbits (both Ptolemy’s and Copernicus’s original), and stars who were regarded as immaterial and therefore distinct from anything on Earth. To see the patterns that eventually became elliptical, he had to imagine the planets were both bodies like Earth, and traveling around one focus of an elliptical orbit. That took a new way of seeing.
With the help of the shiny new JWST, we will be looking more closely at old galaxies, but also more closely at exoplanets. And we’ll be looking for life. To see life on exoplanets, however, we have to think about life in different ways. What are the possible biosignatures for life on planets that are chemically different from our own? What patterns, what kind of organization, do we need to see? Already, as Atlantis has discussed, the prospect of looking at life on exoplanets has inspired scientists to adjust their view. What other new ways of seeing will these telescopes inspire?
One thing is for sure, Atlantis looks forward very much to the images that Jamesy sends back to Earth — for there is nothing our ship loves more than considering the life of the cosmos by new light.