Excavated illegally in 1999 in Saxony-Anhalt, Germany, the extraordinary Nebra Sky Disc is considered both the first known portable astronomical instrument and the oldest-known graphic depiction of celestial objects in human history.
Made of a blue-green copper inset with lustrous gold, the twelve-inch-wide disc contains an arrangement of seven stars probably representing the Pleiades. They’re in between a crescent moon on the right and either the full moon or sun in the center. Two golden bands at the disc’s edge (one is missing) span eighty-two degrees, corresponding to the angle between sunset at the winter and summer solstices at the latitude where it was found.
In this foldout image from the medieval encyclopedia Liber floridus (Book of Flowers), Earth is depicted surrounded by the orbits of the planets, which cut into an early example of a graph depicting planetary motion through time (the red diagonal, seen at an oblique angle). At the bottom, Venus, the sun, and the moon move from their respective spheres into the graph.
Compiled and written in his own hand between 1090 and 1120 by Lambert, the canon of St. Omer, in northern France, the encyclopedia encompasses astronomical, biblical, geographical, and natural history subjects. India is visible at the top of the map of the Earth, following medieval convention, in which Asia was frequently at the top, thus “Orienting” the globe. Liber floridus is considered the first encyclopedia of the High Middle Ages; this is from the original manuscript.
Circa 1600 A.D.
The oldest-known map of the moon from naked eye observations, drawn by English physician and physicist William Gilbert and not published until 1651 in his De mundo nostro sublunari philosophia nova (New Sublunary Philosophy of the World).
Gilbert believed that the lighter areas of the moon were water, and the darker, land—the exact opposite of the prevailing views of the time. Here, what we still call the lunar mare, or “seas,” are depicted as islands. The moon is of course utterly dry.
The sun does in fact occasionally exhibit dark spots. These form in areas where magnetic field lines converge, producing cooler regions of “only” about 3,000–4,000 degrees Celsius (by contrast with their surroundings of 5,000 degrees Celsius or higher).
Sunspots have been observed for more than two thousand years, but in the seventeenth century, astronomers devised new ways to view them, including a telescope-based projection device known as a helioscope. If this etching from Galileo’s 1613 book, Istoria e dimostrazioni intorno alle macchie solari (History and Demonstrations Concerning Sunspots), is practically photographic in its precision, it’s because it is in fact the result of directly tracing the projected image of the sun.
The geocentric Ptolemaic cosmos, from Andreas Cellarius’s lavish Baroque Harmonia macrocosmica (Cosmic Harmony), one of the high points among seventeenth-century celestial atlases. Orbiting a large central Earth, the planets are depicted as star-like shapes, each identified with its traditional symbol. The zodiac, divided into twelve thirty-degree divisions of celestial longitude, defines the apparent path of the sun through the constellations as seen from Earth.
The axis of the universe is defined by the terrestrial poles, and the Earth’s equator is projected outward, creating a celestial equator as well. Ptolemy himself might be represented by one of the figures on the lower right, in a crumbling Alexandria, possibly also symbolic of the decline of his cosmological design, following the revolutionary findings of Copernicus.
Another plate from Andreas Cellarius’s Harmonia macrocosmica, one of the greatest celestial atlases. The moon has been used to mark time and determine when to plant and harvest since before recorded history. Here Cellarius depicts lunar phases, which are due to its varying orientation in relation to the sun when viewed from Earth.
The sun’s apparent path is defined by a ring around what appears to be a smog-shrouded Earth. That cloud represents the Aristotelian idea that all the elements are circumscribed by the moon’s sphere, with everything beyond uncorruptible and unchanging, even in movement. The two smaller flanking diagrams are copied almost unchanged from Hevelius’s Selenographia, a common practice of the time.
Depiction of a subterranean network of molten lava from German Jesuit polymath Athanasius Kircher’s book Mundus subterraneus (Subterranean World). Kircher, who reportedly had himself lowered into the crater of a restive Mount Vesuvius in 1638, has been described as “one of the last thinkers who could rightfully claim all knowledge as his domain.” He developed a theory involving intertwined ducts of water and fire reaching down to the core of the planet.
By attempting to understand the subterranean structures of the planet and how they modify its surface features, Kircher could be said to have exhibited a “planetary” consciousness three centuries before the Gaia hypothesis proposed that we look at Earth as a giant self-regulating system.
This map of the solar system by one Hall Colby is notable for one absence and several presences. While Colby’s map does portray planet Uranus and five of its moons, that’s not particularly notable, because Uranus had been discovered by John Herschel sixty-five years earlier.
Among the interesting presences, then, are four “planets” visible here between the orbits of Mars and Jupiter: Vesta, Juno, Ceres, and Pallas. All were discovered in the first decade of the nineteenth century, and all were considered planets until the 1860s, when a tide of discoveries of ever-smaller objects in similar orbits demoted them to the rank of mere asteroids. (The four largest objects in the asteroid belt, all are still considered asteroids except Ceres, which is now a dwarf planet, the only one in the inner solar system. Pluto, missing here, has also been classified as a dwarf planet since 2006.)
Another notable presence, if you look closely at the detail view of Colby’s map to the right, is that of a planet inside the orbit of Mercury: Vulcan. Although it may sound like it comes from Star Trek, Vulcan first entered the language of popular culture when its existence within this solar system was predicted by French mathematician Urbain Le Verrier in 1843. Le Verrier was so sure he named it, and promoted it widely in the hopes that astronomers would confirm his “discovery.” They tried for decades but came up short.
As for the notable absence in Hall Colby’s map, it’s our current seventh of eight planets: Neptune. That’s because Neptune wasn’t discovered until September 24, 1846—months after this map, which was intended for schools, was printed. But what’s truly interesting is that Neptune was discovered due to the prediction of a French mathematician: one Urbain Le Verrier.
Professor Orlando Ferguson refutes the “globe theory” in this broadsheet bulletin from Hot Springs, South Dakota, proposing instead a kind of four-cornered, roulette-wheel world. Note the sun, moon, and north star all suspended on wands projecting from the pole.
Ferguson’s cosmology didn’t catch on.
This is a geological map of the south polar region of the moon. The Orientale basin continues to dominate the left side of the projection, with all the blue shadings there associated with it. The irregular oblong patch with denim diagonal lines near the center represents terrain still unsurveyed at the time this map was released.
The large tan splotch just below and to the right of the South Pole is the two-hundred-mile-wide Schrodinger crater, one of the few areas on the moon that shows signs of relatively recent volcanic activity. The maroon patch within the baby-blue area at the center of the crater signifies what has been identified as pyroclastic deposits centering on a volcanic vent.
The Shackleton crater, the small olive green patch located directly at the lunar south pole (and embedded in the area with diagonal lines), is thought to contain ice deposits in its perpetually shaded depths. Such deposits could become very important if we ever colonize the moon.
Supercomputer simulation of a sunspot. In this striking image created by researcher Matthias Rempel and collaborators, the highly complex filaments that flow between a sunspot’s dark center and lighter outer region have been produced in exquisite detail by simulating the magnetic forces at play using a supercomputer at the National Center for Atmospheric Research (NCAR).
Sunspots are frequently at the locus of solar prominences, with solar flares and coronal mass ejections all associated with the highly magnetically active regions where they occur. This image, effectively a still culled from the first comprehensive 3-D model of a sunspot, was created after NCAR received an IBM supercomputer capable of performing 76 trillion calculations per second.