Terpischore: The muse of dancing
A poet seeking inspiration, a musician struggling to compose a sublime melody, a historian in need of proper perspective or a dancer striving to master the art of fluid motion must each summon their respective muse. Whereas the poet calls on Calliope ,Erato or Polyhymnia -the muses of Epic, Love and Sacred poetry, respectively-. a musician prays to Euterpe as a historian pays homage to Clio. The dancer, however, derives divine inspiration from Terpischore, the muse of dancing. Ironically, Terpischore is hardly ever seen dancing herself, the above image excepted. She is generally seated while happily strumming on the lyre. Widely regarded as the happiest of the nine muses, Terpischore's principal function is to induce others to dance, if not necessarily to her music, than to that of anyone else.
As is true of the other muses, Terpischore is the daughter of Zeus and Mnemosyne, the goddess of memory. This lineage make sense when one remembers that ancient poets and musicians did not record their work in books or on paper, but, instead, relied on their own recall. Considering the substantial lengths of some epic songs and poems, the task of committing it all to memory was a daunting one. Not only did the muses facilitate the development of creative works, they also imparted their prodigious memories onto those they inspired. Today, what with the advent of printing presses and flash drives, such memory assistance is no longer necessary. However, in this glorious age of exponentially increasing human creativity, inspiration is more in demand than ever.
The Terpishoreans are no exception. The art of dancing has evolved into myriad types all around the world, from the Samba, to the Chinese Dragon dance, Salsa, Ballet, Tango, Kabuki, Waltzes, and variegated other ways of expressing the deepest emotions through the ancient practice of coordinated bodily movements. Though most of these dance forms would have been foreign to the original Terpischore who resided along Mt. Helicon, she would have derived the greatest delight from watching the art of the dance thriving in almost every human community.
The muses remain one of the most beloved of all the mythological realm's denizens simply because they, more than any other deity, exist to draw out the finest aspects of each mortal. Moreover, the muses always cultivate genius without punishing hubris. To them, creating shall always remain an absolute good while ascending the brightest heaven of invention can never become an intolerable impertinence.
THE SOUTHWORTH PLANETARIUM
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2020-2021: LXXXV
THE DAILY ASTRONOMER
Monday, February 8, 2021
Exploratorium XVIII: Earth's Second Moon
Location
Earth orbit
Time
Now
There it goes: a small, clunky mini-moon that fell into a temporary Earth orbit in September 2020. After it attained its minimum distance (140,000 miles from Earth) on Feb 2nd, this tumbling little body started moving away from Earth and will establish a Sun-centered orbit by mid March. Astronomers have dubbed this little interloper 2020 SO, otherwise known as "Earth's second moon." Other scientists know of it as a 1960's rocket booster. Yes, that is correct. Our planet's second moon is a human-made construct, one that our planet is about to lose forever.
Astronomers using the Pan-STARRS1 telescope in Hawaii first discovered this strange little "world" on September 17, 2020 and gave it the designation 2020 SO. They initially classed it as an Apollo-type asteroid, defined as an asteroid with a perihelion distance less than 1.017 AU. (An AU, or "astronomical unit" equals Earth's mean heliocentric distance of approximately 93 million miles.) Soon after its discovery, 202o SO exhibited motions inconsistent with such asteroids. It moved too slowly, clocking in at a mere 1,800 miles per hour when passing by Earth's moon. Asteroids moving along similar trajectories are capable of attain speeds more than five times higher. Another curiosity was its orbital duration, equal to 1.06 Earth years. Bodies with orbits similar to Earth tend to actually be objects launched from Earth. Radar images of this mini-moon revealed that its shape was elongated, measuring 6 - 14 meters, consistent with the Atlas LV-3C Centaur-D.
Atlas LV-3C Centaur-D
Confirmation that this object was indeed such an object came from observations made with NASA's infrared telescope, also in Hawaii and from orbital analysis conducted at the Jet Propulsion Laboratory in Pasadena. This interloping booster rocket was believed to have launched Surveyor 2 into orbit in 1966. While most booster rockets return to Earth and land, hopefully, in the ocean, that rocket was launched into space and became lost to humans for decades. Ironically, it has been making close passes to Earth since its launch, including a rapid fly by in 1966.
During the intervening years, this rocket booster's trajectory has been altered by the slightest of all pressures: solar radiation. While this radiation pressure has little effect on large tumbling mountain-sized asteroids, it can certainly affect these booster rocket shells, which are hollow and much lighter. The radiation influence pushed it out into a different orbit, causing it to vanish from view until its discovery last year.
Now, after having spun around Earth repeatedly, this long lost booster is about to leave Earth forever and establish an orbit around the Sun, like so many other mini-moons that once spun around our world. We bid adieu to the rocket that propelled Surveyor-2 to the moon, where, lamentably, it perished in a fiery crash. At least its booster shall persist for quite a long time as it follows a lazy orbit around the Sun.
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