Divine Geometer

Divine Geometer

After three years of calculation Johannes Kepler believed he had found the correct values for a Martian circular orbit, which matched ten of Tycho’s observations within two minutes of arc. Now, there are 60 minutes of arc in an angular degree, and 90 degrees, a right angle, from the horizon to horizon. So a few minutes of arc is a very small quantity to measure – especially without a telescope. It is one-fifteenth the angular diameter of the full Moon as seen from Earth.

But Kepler’s replenishable ecstasy soon crumbled into gloom – because two of Tycho Brahe’s further observations were inconsistent with Kepler’s orbi, by as much as eight minutes of arc:

Divine Providence granted us such a diligent observer in Tycho Brahe that his observations convicted this … calculation of an error of eight minutes; it is only right that we should accept God’s gift with a grateful mind… If I had believed that we could ignore there eight minutes, I would have patched up my hypothesis accordingly. But, since it was not permissible to ignore, those eight minutes pointed the road to a complete reformation in astronomy.

Kepler was shaken at being compelled to abandon a circular orbit and to question his faith in the Divine Geometer. Having cleared the stable of astronomy of circles and spirals, he was left, he said, with “only a single cartful of dung”, a stretched-out circle something like an oval.

“The truth of nature, which I had rejected and chased away, returned by stealth through the back door, disguising itself to be accepted… Ah, what a foolish bird I have been” (Johannes Kepler). Image:  © Megan Jorgensen (Elena)

Eventually, Kepler came to feel that his fascination with the circle had been a delusion. The Earth was a planet, as Copernicus had said, and it was entirely obvious to Kepler that the Earth, wracked by wars, famine, pestilence and unhappiness, fell short of perfection. Kepler was one of the first people since antiquity to propose that the planets were material objects made of imperfect stuff like the Earth. And if planets were “imperfect”, why not their orbits as well? He tried various oval-like curves, calculated away, made some arithmetical mistakes (which caused him at first to reject the correct answer) and months later in some desperation tried the formula for an ellipse, first codified in the Alexandrian Library by Apollonius of Perga. He found that it matched Tycho’s observations beautifully: “The truth of nature, which I had rejected and chased away, returned by stealth through the back door, disguising itself to be accepted… Ah, what a foolish bird I have been”.

Kepler had found that Mars moves about the Sun not in a circle, but in an ellipse. The other planets have orbits much less elliptical that that of Mars, and if Tycho had urged him to study the motion of, say, Venus, Kepler might never have discovered the true orbits of the planets.

A Romantic Girl

A Romantic Girl

In the late 1960s, the Soviet Union succeeded in landing space vehicles on the surface of Venus. They were the first spacecraft of the human species to set down in working order on another planet. Over a decade earlier, American radio astronomers, confined to Earth, had discovered that Venus was an intense source of radio emission. The most popular explanation had been that the massive atmosphere of Venus trapped the heat through a planetary greenhouse effect. In this view, the surface of the planet was stifling hot, much too hot for crystal cities and wondering Venusians.

Ellie longed for some other explanation, and tried unsuccessfully to imagine ways in which the radio emission could come from high above a clement Venus surface. Some astronomers at Harvard and MIT claimed that none of the alternatives to a broiling Venus could explain the radio data. The idea of so massive a greenhouse effect seemed to her unlikely and somehow distasteful, a planet that had let itself go. But when the Venera spacecraft landed and in effect stuck out a thermometer, the temperature measure was high enough to melt tin of lead. She imagined the crystal cities liquefying (although Venus wasn’t quite that hot), the surface awash in silicate tears.

A Romantic Girl - romantic Interlude. Photo : Elena

But at the same time she had to admire how powerful radio astronomy was. The astronomers had sat home, pointed their radio telescopes at Venus, and measured the surface temperature just about as accurately as the Venera probes dis thirteen years later. Elle had been fascinated with electricity and electronics as long as she could remember. But this was the first time she had been deeply impressed by radio astronomy. You stay safely on your own planet and point your telescope with its associated electronics. Information about other worlds then comes fluttering down through the feeds. She marveled at the notion.

Ellie began to visit the university’s modest radio telescope in nearby Harvard, Massachusetts, eventually getting an invitation to help with the observations and the data analysis. She was accepted as a paid summer assistant at the National Radio Astronomy observatory in Green Bank, West Virginia, and upon arrival, gazed in some rapture at Grote Reber’s original radio telescope, constructed in his backyard in Wheaton, Illinois, in 1938, and now serving as a reminder of what a dedicated amateur can accomplish.

Reber had been able to detect the radio emission from the center of the Galaxy when no one nearby happened to be starting up the car and the diathermy machine down the street was not in operation. The Galactic Center was much more powerful, but a diathermy machine was a lot closer.

The atmosphere of patient inquiry and the occasional rewards of modest discovery were agreeable to her. They were trying to measure how the number of distant extragalactic radio sources increased as they looked deeper into space. She began to think about better ways of detecting faint radio signals. In due course, she graduated Cum Laude from Harvard and went on for graduate work in radio astronomy at the other end of the country, at the California Institute of Technology.

Ellie was a romantic, she had known it for years. Image: Megan Jorgensen (Elena)

The Cruelest Lies are Told in Silence

The Cruelest Lies are Told in Silence

Two hundred fifty six images of the left world swam by on the left. Two hundred fifty-six images of the right world glided by on the right. Ellie integrated all 512 images into a wraparound view of her surroundings.

She was deep in a forest of great waving blades, some green, some etiolated, almost all larger than she. But she had no difficulty clambering up and over, occasionally balancing precariously on a bent blade, falling to the gentle cushion of horizontal blades below, and then continuing unerringly on her journeys.

She could tell she was centered on the trail and it was tantalizingly fresh.“What worries me the most”, she continued, “is the opposite, the possibility that they’re not trying. They could communicate with us, all right, but they’re not doing it because they don’t see any point to it. It’s like the ants. They occupy the same landscape that we do, but they have plenty to do, things to occupy themselves. On some level they are very well aware of their environment. But we don’t try to communicate with them, so I don’t think they have the foggiest notion that we exist.

A large ant, more enterprising than her fellows, had ventured onto the tablecloth and was briskly marching along the diagonal of one of the red and white squares. Suppressing a small twinge of revulsion, Ellie gingerly flicked it back onto the grass – where it belonged.

Heard melodies are sweet, but those unheard are sweeter and the cruelest lies are often told in silence (Quotations from M. Jorgensen). Image: © Megan Jorgensen (Elena)

Unmanned Planetary Exploration

Unmanned Planetary Exploration

Intelligent life on Earth first reveals itself through the geometric regularity of its constructions. If Percival Lowell’s canal network really existed, the conclusion that intelligent beings inhabit Mars might be similarly compelling. For life to be detected on Mars photographically, even from Mars orbit it must likewise have accomplished a major reworking of the surface. Technical civilization, canal builders, might be easy to detect. But except for one or two enigmatic features, nothing of the sort is apparent in the exquisite profusion of Martian surface detail uncovered by unmanned spacecraft.

However, there are many other possibilities, ranging from large plants and animals to microorganisms, to extinct forms, to a planet that is now and was always lifeless. Because Mars is farther from the Sun than is the Earth, its temperatures are considerably lower. Its air is thin, containing mostly carbon dioxide but also some molecular nitrogen and argon and very small quantities of water vapor, oxygen and ozone. Open bodies of liquid water are impossible today on Mars because of the atmospheric pressure on the planet is too low to keep even cold water from rapidly boiling. There may be minute quantities of liquid water in pores and capillaries in the soil. The amount of oxygen is far too little for a human being to breath. The ozone abundance is so small that germicidal ultraviolet radiation from the Sun strikes the Martian surface unimpeded. Could any organism survive in such an environment?

The Universe is fragile. It must be cherished. Image: © Megan Jorgensen

The Soviet Union maintained an active program of unmanned planetary exploration. Every year or two the relative positions of the planets and the physics of Kepler and Newton permitted the launch of a spacecraft to Mars and Venus with a minimum expenditure of energy. Since the early 1960’s the Soviet Union missed few such opportunities. Soviet persistence and engineering skills have eventually paid off handsomely.

Five Soviet spacecraft – Veneras 8 through 12 – have landed on Venus and successfully returned data from the surface, no insignificant feat in so hot, dense and corrosive a planetary atmosphere. Yet despite many attempts, the Soviet Union has never landed successfully on Mars – a place that, at least at first sight, seems more hospitable, with chilly temperatures, a much thinner atmosphere and more benign gases; with polar ice caps, clear pink skies, great sand dunes, ancient river beds, a vast rift valley, the largest volcanic construct, so far as we know, in the solar system, and balmy equatorial summer afternoons. It is a far more Earth-like world than Venus.

The Bikini Explosion

The Bikini Explosion

The Hiroshima Explosion, unlike the subsequent Nagasaki explosion, was an air burst high above the surface, so the fallout was insignificant.

But on March 1, 1954, a thermonuclear weapons test at Bikini in the Marshall Islands detonated on the tiny atoll of Rongalap, 150 kilometers away, where the inhabitants likened the explosion to the Sun rising in the West. A few hours later, radioactive ash fell on Rongalap like snow. The average dose received was only about 175 rads, a little less than half the dose needed to kill an average person. Being far from the explosion, not many people died. Of course, the radioactive strontium they ate was concentrated in their bones, and the radioactive iodine was concentrated in their thyroids. Two-thirds of the children and one third of the adults later developed thyroid abnormalities, growth retardation or malignant tumors. In compensation, the Marshall Islanders received expert medical care.

The global balance of terror holds hostage the citizens of the Earth. Image: © Megan Jorgensen (Elena)

The yield of the Hiroshima bomb was only thirteen kilotons, the equivalent of thirteen thousand tons of TNT. The Bikini Test yield was fifteen megatons. In a full nuclear exchange, in the paroxysm of thermonuclear war, the equivalent of a million Hiroshima bombs would be dropped all over the world.

At the Hiroshima death rate of some hundred thousand people killed per equivalent thirteen-kiloton weapon, this would be enough to kill a hundred billion people. But there were less than seven billion people on our planet in the early XXI Century. Of course, in such an exchange not everyone would be killed by the blast and the firestorm, the radiation and the fallout – although fallout does last for a longish time: 90 percent of the strontium 90 will decay in 96 years; 90 percent of the cesium 137, in 100 years; 90 percent of the iodine 131 in only a month.