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Humankind has finally reached up and touched the sun–well, figuratively anyway, by means of NASA’s Parker solar probe. The spacecraft is the fastest human-created object ever made (so far) and travels at a blistering 532,000 kilometers per hour (330,000 mph). Since its launch in 2018, it has been circling closer and closer to the sun, and yesterday mission controllers announced that the craft had finally flown through the corona of the star (which can reach toasty temperatures of one million degrees Kelvin (1,800,000 degrees Fahrenheit)). Fortunately the upper atmosphere portion of the sun which the craft flew through was a mere 2500 degrees Fahrenheit and the crafts stout carbon shielding protected its sensitive instruments just fine.
During its time in the hot seat (which actually occurred back in April, but which is just being announced now), the Parker solar probe sampled solar particles and analyzed the sun’s magnetic fields so that scientists can try to understand more about the fundamental dynamics of stellar physics. The probe will continue to circle the sun during the course of its seven year mission and should provide ample material for physicists to analyze.
Corona Borealis is a semicircular constellation in the northern sky between Hercules and Boötes. It is of mild interest to astronomers for containing two interesting variable stars: (1) T Coronae Borealis, the so-called “Blaze Star”, which is a recurring nova binary star; and (2) R Coronae Borealis, a yellow supergiant which periodically dims from magnitude 6 to magnitude 14 and then brightens back up (possibly because it is producing carbon).
The constellation is much more interesting to classical artists since a myth about its creation gives artists their symbol for deification. Ariadne was the daughter of Minos, king of Crete who became judge of the underworld after his death and Queen Pasiphae (who was herself a daughter of the sun). The princess fell in love with Theseus, an Athenian hero who was to be sacrificed to the Minotaur, a bull-headed monster who lived in the labrynth beneath the palace. With the help of the wise artificer, Daedalus, Ariadne rescued Theseus and together they fled from Crete (just barely escaping destruction at the hands of Talos, the giant bronze robot which guarded the island).
Ariadne (John William Waterhouse, 1898, oil on canvas)
Once they had escaped, the faithless Theseus abandoned Ariadne sleeping on the island of Naxos. The sleeping maiden was spied by Dionysus who chose her as a consort. She was given immortality and godhood as soon as she was married and Dionysus hung her wedding crown of stars in the sky as the constellation Corona Borealis (maybe it has so many variable stars because it was sacred to the god of intoxication).
Bacchus and Ariadne (Roman sarcophagus ca. 170-180 BC)
This seems like a weird narrative and it probably reflects Greek confusion about the proper status of Ariadne (whom some scholars identify as a Cretan serpent goddess from the Mycenaean era). But irrespective of her origin or how she came by her divinity Ariadne has proven to be a favorite subject of visual artists from classical times onward. Many artists prefer to portray her beautiful, naked, and asleep (and you can easily find many such paintings and statues on the web) but nearly as many are fascinated by her apotheosis—the moment she receives her godhood and escapes mortality.
Bacchus and Ariadne (Titian, 1523–24, oil on canvas)
Perhaps the finest of these paintings was created by the peerless hand of Titian for the Alabaster Room in the palace of Duke Alfonso d’Este–who specifically commissioned the world’s finest bacchanal paintings for his room (a project so fascinating and strange that the Alabaster Room has been virtually created online). The painting shows the moment when Dionysus reveals himself to the bewildered Ariadne with all of his divine retinue. The beautiful god leaps from his leopard-drawn chariot and flies down towards her as maenads and satyrs wildly revel behind him. If you aren’t too distracted by the naked wild man covered in snakes, or by the dismembered donkey, or by the beautiful columbines and irises which bloom purple beneath the feet of the god’s inebriated followers, you will notice the constellation Corona Borealis glowing in the sky above Ariadne’s head.
Titian’s vision was so splendid and influential that other artists adopted the crown of stars as a symbol of apotheosis. The crown of immortality appears in other works as heroes step across the threshold of godhood. It is a reoccurring representation of our desire to step beyond humanity and become deathless divine beings.
Madonna in Glory (Carlo Dolci, 1670, Oil on canvas)
A day ago an international team of stellar physicists announced that the sun’s surface is covered with thousands of searing hot plasma super tornadoes each of which is the size of a large continent on Earth. Using a combination of a space telescope and a ground telescope, researchers discovered that each of these plasma vortexes spins at velocities up to 14,500 kilometers (9,000 miles) an hour.
(CREDIT: Wedemeyer-Böhm: Parts of the image produced with VAPOR)
The mystery of why the corona of the sun is 300 times hotter than the star’s surface has long vexed scientists. The surface of the sun is a balmy 5,526 degrees Celsius (9,980 Fahrenheit), while temperatures in the corona peaks 2 million degrees Celsius (3.5 million Fahrenheit). The discovery of these giant fast-moving storms provides a new mechanism by which heat is transferred through the sun’s atmosphere and ejected into the corona. Energy locked in the powerful magnetic vortexes is effectively self-insulated and does not heat the solar photosphere and chromosphere as much as the corona (where the storms widen and dissipate).
The Sun photographed by the Atmospheric Imaging Assembly (AIA 304) of NASA’s Solar Dynamics Observatory
Sven Wedemeyer-Böhm, a Norwegian scientist working on the team was quick to stress that the tornadoes are likely one of several complicated energy transfer mechanisms by which heat reaches the solar corona. However it seems that there are more than 11,000 of these huge plasma tornadoes on the solar surface at any given time.
The Romans made use of many crowns during the time of the Republic. Some proclaimed exceptional soldiers or dominant politicians. Other crowns were worn by athletes, brides, or festival celebrants. An entire list of Roman coronae can be found here. Later on, as the empire began to crumble, Emperors might wear jeweled diadems, but in the republic a very different sort of crown stood above all the rest.
The grass crown was the highest reward a Roman military man could receive during the time of the Roman Republic (and for a brief period at the beginning of the Roman Principate). A general could only win the grass crown by saving an entire army. Well, actually, the crown was once given to a mere centurion for saving an army–so it was saving an army that was important. Usually such a thing could only be accomplished by commanders. A mere handful of the greatest Roman warriors ever received this singular honor.
The crown was woven out of grass, weeds, and wildflowers taken from the ground where the person receiving the award saved the army. It was made by soldiers and presented by them to their savior, so it may have lacked the sophistication and loveliness of fancier wreaths and garlands. Nevertheless the Romans esteemed it above all other headgear. Pliny the Elder described the grass crown in Chapter XXII of his work The Natural History (translated by John Bostock):
Of all the crowns with which, in the days of its majesty, the all-sovereign people, the ruler of the earth, recompensed the valor of its citizens, there was none attended with higher glory than the crown of grass. The crowns bedecked with gems of gold, the vallar, mural, rostrate, civic, and triumphal crowns, were, all of them, inferior to this: great, indeed, was the difference between them, and far in the background were they thrown by it. As to all the rest, a single individual could confer them, a general or commander on his soldiers for instance, or, as on some occasions, on his colleague: the senate, too, exempt from the cares and anxieties of war, and the people in the enjoyment of repose, could award them, together with the honours of a triumph.
But as for the crown of grass, it was never conferred except at a crisis of extreme desperation, never voted except by the acclamation of the whole army, and never to any one but to him who had been its preserver. Other crowns were awarded by the generals to the soldiers, this alone by the soldiers, and to the general. This crown is known also as the “obsidional” crown, from the circumstance of a beleaguered army being delivered, and so preserved from fearful disaster. …
The crown thus presented was made green grass, gathered on the spot where the troops so rescued had been beleaguered. Indeed, in early times, it was the usual token of victory for the vanquished to present to the conqueror a handful of grass; signifying thereby that they surrendered their native soil, the land that had nurtured them, and the very right even there to be interred—a usage which, to my own knowledge, still exists among the nations of Germany.
Pliny went on to list the men who received the grass crown. It is a short list of Rome’s greatest victors. Here is that list of peerless Roman commanders with a brief explanation:
- Lucius Siccius Dentatus (a general during the great civil struggles between the plebians and the patricians)
- Publius Decius Mus (received two grass crowns—one from his own army, and a second from the legions he had rescued)
- Fabius Maximus (received the crown for creating and employing “the Fabian strategy” a series of delaying tactics by which Hannibal was ultimately expelled from Italy)
- Marcus Calpurnius Flamma (a commander who led 300 volunteers on a succesful suicide mission to free the consular army which was caught in a defile during a batule in the First Punic War)
- Scipio Aemilianus Africanus (adopted grandson of the famous Roman general of the same name: Scipio the younger won his his grass crown in the final Punic war–which saw the utter destruction of Carthage)
- Gnaeus Petreius Atinas (the previously mentioned centurion, who saved a legion during the Cimbri wars by means of good leadership and heroic battlefield prowess )
- Lucius Cornelius Sulla (the great dictator won the crown in fishy circumstances during the Social War at Nola [Pliny is dismissive of the award–and of Sulla])
- Quintus Sertorius (who defeated several large armies campaigning in Spain–but may not have recived the grass crown[Pliny’s language is unclear])
- Augustus (the crown was presented to Augustus by the Senate but was it was a political homage to an emperor rather than an army’s reward for its general.)
After Augustus, the grass crown exits history. It lingers only as a memory of the warlike virtues of the Roman Republic.
ferrebeekeeper 