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216 Kleopatra

216 Kleopatra

It’s time for Ferrebeekeeper to get back out to space.  This grotesque gray hambone-looking thing is a metallic asteroid approximately the size of New Jersey known as 216 Kleopatra.  The asteroid was discovered in 1880 by Austrian astronomer Johann Palisa when he was director of the Austrian naval observatory at the great Austrian naval port of Pula (!). The asteroid is 217 kilometers long by 94 kilometers deep by 81 kilometers long (135 miles by 58 miles by 50 miles).  It is composed of slurry of metal, dust, and…nothing: between 30 to 50% of the asteroid’s volume is empty space (which makes it sound a lot like the consumer goods for sale in American stores).

216 Kleopatra has been the subject of a fair amount of human scrutiny.  In 2008, a team of astronomers working from Hawaii’s Keck observatory (at the summit of Mauna Kea in Hawaii discovered two tiny moons orbiting the asteroid.  These moons have diameters of about 5 km and 3 km respectively and they are named Alexhelios and Cleoselene for Cleopatra’s children.


An obvious question is what knocked this doughty asteroid into a strangely shaped cloud of weird slurry and little moons.  The most obvious answer is an oblique impact, which astronomers estimate occurred about a hundred million years ago.  I wonder what other secrets this giant rubble pile in space is hiding. rotates, as seen in this stunning animation.

Also…it rotates, as seen in this stunning animation.

surface_area_largeToday features a short but vivid post borrowed from the futurist/science fiction/space blog io9 (which in turn took it from XKCD). Above is a map of all the surfaces of the solar system’s planets and moons flattened out and stitched together. The map was created by Randall Munroe and it does a superb job of explaining the relative size of rocky objects in the solar system. For obvious reasons the gas giants (and the sun!) have been excluded, but so too have small rocks and dust. For fun (um, I hope), the mapmaker also included an area equivalent to all human skin–which, distressingly, seems to be about the size of Hainan.

Russian concept art for a cloud colony in the upper atmosphere of Venus, (proposed in 1970s)

Russian concept art for a cloud colony in the upper atmosphere of Venus, (proposed in 1970s)

This map also emphasizes my most ardent fantasy of solar system colonization: I don’t really want to set up shop on Umbiel or Ceres, but I have a long-lasting interest in colonizing Venus. Sadly most of the rest of humankind is having trouble grasping this concept (possibly because the surface of Venus is a molten hellscape featuring boiling lead, sulfuric acid rain, and crushing pressure).  Remember though, we don’t need to ever go down to the Venutian surface: we can hang around in floating bouncy castles drifting through the balmy spring at the top of the atmosphere. Imagine taking your family zeppelin out for a night on the floating town! All of the people who express such an unwholesome interest in cold resource-poor Mars should pause to reexamine its relative area on Mr. Munroe’s excellent map!

Mars, Earth, Venus

Left to right: Mars, Earth, Venus

The Hannover Military Band

The Electorate of Brunswick-Lüneburg (colloquially known as the Electorate of Hanover) was a principality within the Holy Roman Empire.  In the mid eighteenth century, the region was ruled by the Prince Elector, Georg II.  A series of religious wars and a strange quirk of fate had made the house of Brunswick-Lüneburg the heirs to the British throne.  Prince Elector Georg II was therefore better known to his English subjects and to history as King George II.  In 1755, George II ordered his Hanoverian Guards Regiment to England.  The Hanover Military band went with the Guards.  One of the oboists of the band was named Friedrich Wilhelm Herschel.  Friedrich was something of a musical prodigy: he also played the violin, the cello, the harpsichord and the organ.   When the guards came to England, he liked the country and he left the band to move there permanently.  He accepted the position as first violin and soloist for the Newcastle orchestra and later became the organist of the Octagon Chapel in Bath (a chapel attached to a very fashionable spa).  Throughout his career Frederick William Herschel (for he had anglicized his name) composed a great many musical works including 24 symphonies, numerous concertos, and a large canon of church music.

Frederick’s music is forgotten today, but later in his life he found his true calling.  As his musical career progressed, he became more and more deeply fascinated by lenses and mathematics. At the age of 35, he met the Reverend Dr. Nevil Maskelyne who was Astronomer Royal and Director of the Royal Observatory in Greenwich. Herschel began making mirror telescopes for Maskelyne, personally grinding the lenses and mirrors for up to 16 hours a day.  He also looked at the universe through the telescopes he had made and reported his discoveries. What he found made him one of the preeminent scientists in history (he also became extremely wealthy and was granted a knighthood).

The Planet Uranus (or "Georgium sidus" as Herschel originally named it)

Herschel is most famous for discovering Uranus, the first planet to be found since the depths of antiquity.  His other discoveries and ideas are perhaps even more remarkable. He was first to find out that the solar system is moving through space.  He coined the word “asteroid” as a name for such objects.  By observing Mars he determined its axial tilt and found that the Martian ice caps fluctuate in size. His attempts to determine if there was a link between solar activity and the terrestrial climate were unsuccessful (because of a lack of data), but formed the basis for successful work concerning both climatology and stellar physics.  Astonishingly, Herschel discovered infrared radiation, the first non-visible electromagnetic radiation to be known.  He accomplished this by passing sunlight through a prism and holding a thermometer just beyond the red end of the visible spectrum.  He found two new moons of Saturn and two moons of Uranus.  He correctly concluded that the Milky Way is a disk.  He debunked the notion that double stars were optical doubles and showed that they are truly binary stars (thus demonstrating that Newton’s laws extend beyond the solar system).

Sir Frederick William Herschel, 1738 - 1822 (painted by Lemuel Francis Abbott in 1785)

In honor of his amazing career, numerous objects, devices, institutes and features around the solar system and beyond are named after Herschel (including the giant crater on Saturn’s moon Mimas). Few people have contributed so greatly to science or changed the conception of everything as much as this gifted Saxon oboist!

Ye Olde Ferrebeekeeper Archives

August 2020