THE SOUTHWORTH PLANETARIUM
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Founded January 1970
Julian date: 2458756.5
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THE DAILY ASTRONOMER
Monday, September 30, 2019
Monday, September 30, 2019
The Heavenly Elements
Well...darn!
After a year's hiatus, the Brain of Portland quiz series returned last Friday. Contained within the very first BoP quiz was a SOMEWHAT embarrassing error. Let's revert back in time to question 19:
19. CHEMISTRY How many elements are named after heavenly bodies?
a. 1
b. 2
c. 3
d. 4
The "correct" answer was d. according to the infallible wizard who writes the DA.
In fact, Edward you dunce, there are 9 heavenly elements!
The answer to question # 19 listed the following four:
Helium
Uranium
Neptunium
Plutonium
No mention of, oh, I don't know, MERCURY or Cerium, Selenium, Palladium or Tellurium. Having omitted the last of these elements might have been a pardonable error. Missing the first of them (MERCURY!), however, was...well, why don't we just move on to the article now...
We decided to make the most of this error by devoting today's DA to the heavenly elements: those named for celestial bodies. We take each in turn and, we hope, don't forget any of them this time
CERIUM
Atomic number: 58
Cerium was named for Ceres, a Sun-orbiting body discovered on the very first day of the 19th century (Jan 1, 1801). Initially classified as a planet, Ceres has since become known as the largest asteroid in the asteroid belt between Mars and Jupiter. (It is now a dwarf planet.) Jons Berzelius and Wilhelm Hisinger discovered the element Cerium in 1803. Berzelius named it Cerium after Ceres, which has been discovered only two years earlier. Mythologically, Ceres was the Roman goddess of the harvest, the counterpart to the Greek Demeter.
HELIUM
Atomic number: 2
During a solar eclipse in 1868, a strange spectral signature appeared that the astronomers observing the event did not expect. English astronomer Norman Lockyear and French astronomer Jules Janssen determined that this enigmatic spectral signature was produced by a hitherto unknown element which Lockyear named "Helium," after the radiant Titan who was said to have conveyed the Sun across the sky with his well-shielded chariot.
MERCURY
Atomic number: 80
Atomic number: 80
Yes, the first planet in the solar system is called "Mercury," named for the winged messenger Mercury, the Roman equivalent of the Greek Hermes. Swift-footed and Sun-silvered Mercury is a perfect celestial body to be the namesake of Mercury, the silvered liquid metal of low viscosity that is bad for the bloodstream and not particularly pleasant to countertops. The original name was hydragyrum, from the Greek for "silver water," hence Mercury's chemical symbol of Hg.
NEPTUNIUM
Atomic number: 93
The first of the transuranic elements, those listed in the periodic table after Uranium, Neptunium was first synthesized in 1940 at the Berkeley Radiation Laboratory by Edwin McMillian and. Philip Abelson. This new element was quickly named Neptunium because it was the 93rd element, immediately following the 92nd element, Uranium. Since Neptune is the next planet away from the Sun after Uranus, it seemed logical to name the element immediately following Uranium after Neptune..
The first of the transuranic elements, those listed in the periodic table after Uranium, Neptunium was first synthesized in 1940 at the Berkeley Radiation Laboratory by Edwin McMillian and. Philip Abelson. This new element was quickly named Neptunium because it was the 93rd element, immediately following the 92nd element, Uranium. Since Neptune is the next planet away from the Sun after Uranus, it seemed logical to name the element immediately following Uranium after Neptune..
and doesn't that bring us neatly to
PLUTONIUM
Atomic number: 94
First synthesized in December 1940 by Edwin McMillian, Glenn Seaborg (of Seaborgium fame), Joseph Kennedy and Arthur Wahl, Plutonium is the 94th element. As it contains 94 protons, was assigned the atomic number of 94. As it immediately followed Neptunium on the periodic table, this second transuranic element was assigned the name "Plutonium." American astronomer Clyde Tombaugh discovered Pluto a decade earlier. At this time, the dark lords of the International Astronomical Union classified it as a planet.
This pellet containing Plutonium emits a constant stream of alpha particles. Such pellets provide energy to devices such as Radioisotopic Thermoelectric generators that power some of the robotic spacecraft.
URANIUM
Atomic number: 92
Martin Heinrich Klaproth first discovered the element Uranium in 1789, merely eight years after William Herschel inadvertently discovered the planet Uranus. For this reason, Klaproth named this element Uranium. (Note the parallel with the naming of the element Cerium.) We should add that in 1896, Henri Becquerel discovered radioactivity by leaving a Uranium sample in a drawer with a photographic plate. The next day he observed the plate and noted that some areas of it were whitened as though by a fog. He later ascribed this "fogging" to particle emission now known as "radioactivity."
PALLADIUM
Atomic number: 43
Like Cerium and Uranium, Palladium was named for a celestial body whose discovery just preceded its own. Heinrich Olbers discovered Pallas in March 1802. (It was found in the same general region as Ceres, the area now known as the "Main Asteroid Belt.") In July 1802, chemist William Hyde Wollston discovered a new noble metal that he named "Palladium," after the "planet" discovered only a few months earlier.
TELLURIUM
Atomic number: 52
Atomic number: 52
The metal named for "Earth," Tellurium was first found in a gold mine in 1782, but was not named until 1798. The word "terrestrial" has a similar derivation for it also is based on Tellus, the Latin word for "Earth." Ironically, Tellurium is more abundant in the Universe as a whole than it is on the planet for which it is named.
SELENIUM
Atomic number: 34
Atomic number: 34
Selenium is named for Selene, one of the many names for the "moon." Discovered in 1817 by Jons Jacob Berzelius and Johan Gottleig Gahn, this element exhibited characteristics that were similar to that of Tellurium that was named about 20 years earlier. For this reason, the 34th element was named for the moon. We now know today that Earth and the moon are chemically similar and dissimilar.
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