December 7 marks the passing of Walter Noddack. Noddack was a German chemist who searched for two elements missing from Mendeleev’s periodic table. The two blank placeholder elements appeared underneath manganese called eka-manganese and dvi-manganese. (eka means 1 and dvi means 2 in Sanskrit). Together with Ida Tacke (who would later become Ida Noddack) and Otto Berg, they began a search to find these two elements.
X-rays can be used to identify elements. Much like visible light, each element has a unique spectrum when exposed to x-rays. Noddack’s team bombarded samples of platinum ores and columbite with x-rays. They detected peaks associated with the predicted values of element 72, dvi-manganese. After processing the samples, they isolated a pure sample of the element. They named the element rhenium after the Latin form of the Rhine, rhenus.
These three chemists also claimed to detect peaks associated with element 43, eka-manganese. They published their discovery and named the element masurium. Unfortunately, their results were never reproduced by others and their claim was never verified. Eka-manganese would be eventually artificially produced by a particle accelerator by Emilio G. Segrè who named the element technetium, after the Greek word for ‘artificial’.
Technetium was eventually discovered in minute quantities in the uranium ore pitchblende. X-ray analysis of samples of pitchblende containing technetium gave spectra very similar to Noddack’s data. Examining the amount of uranium in columbite and relating the amount of technetium associated with uranium makes it possible the Noddack team saw evidence of technetium, but the possibility was very small.
On a similar note, 17 years prior to the Noddack discovery of rhenium, Japanese chemist Masataka Ogawa claimed to discovered eka-manganese using the same techniques. He named his discovery nipponium. Unfortunately, no one could duplicate his results and he lost his claim. Recent studies have shown Ogawa did not discover eka-manganese, but dvi-manganese or rhenium.
Notable Science History Events for December 7
2015 – JAXA’s Akatsuki probe enters Venus orbit.
The Japanese space agency (JAXA) managed to adjust their Akatsuki probe’s orbit to enter the orbit of Venus. The probe failed to enter orbit in 2010 and ended up orbiting the Sun. JAXA fired Akatsuki’s control thrusters at a pre-calculated time and allowed the probe to enter an alternative Venus orbit. The probe began studying the atmospheric dynamics and stratification of Venus’ atmosphere.
1995 – Galileo spacecraft arrives at Jupiter.
NASA’s Galileo spacecraft arrived at the planet Jupiter and entered orbit. It would spend the next 8 years in the Jovian system before purposely burning up in Jupiter’s atmosphere. It carried the first probe to directly measure Jupiter’s atmosphere and was on hand to witness the spectacular collision of the comet Shoemaker-Levy 9.
1993 – Wolfgang Paul died.
Paul was a German physicist who shares half the 1989 Nobel Prize in Physics with Hans G. Dehmelt for their development of the ion trap. The ion trap is a device that uses electric and magnetic fields to capture ions in a vacuum. Paul developed an ion trap that uses radio frequency electric fields using a quadrupole arrangement to capture ions.
1979 – Cecilia Payne-Gaposchkin died.
Payne was an English/American astronomer who was the first to propose the sun was made up primarily of hydrogen. She showed the absorption spectra lines from the sun corresponded to different temperature levels of hydrogen and helium. The common wisdom of the time had the sun’s chemical composition the same as that as Earth.
1972 – Last United States mission to the Moon launched.
Apollo 17 launched from Cape Canaveral on the sixth and final Apollo mission to the Moon. It was also the first (and last) night launch of the Saturn V rocket. Astronauts Eugene Cernan, Ronald Evans and Harrison Schmitt would spend three days on the surface of the Moon. Commander Cernan would be the last person to set foot on the Moon.
1960 – Walter Noddack died.
1925 – Martin Rodbell died.
Rodbell was an American biochemist who shares the 1994 Nobel Prize in Medicine with Alfred Gilman for their discovery of G-proteins and their role in signal transduction within the cell. G-proteins are a family of proteins that work as switches and intermediary between guanosine diphosphate (GDP) and guanosine triphosphate (GTP) to regulate downstream cell processes.
1905 – Gerard Peter Kuiper was born.
Kuiper was a Dutch-American astronomer who discovered the moon Miranda orbiting Uranus and the moon Nereid orbiting Neptune. He also predicted the existence of carbon dioxide in the Martian atmosphere and methane in Titan’s atmosphere that proved to be correct. He described a theory of the origin of the Solar System that suggested it formed from a large cloud of gas. One part of the theory has a disk-shaped belt outside the Solar System filled with millions of comets approximately 30 to 50 astronomical units from the Sun. This belt was discovered in 1992 and named the Kuiper Belt.
1810 – Theodor Schwann was born.
Schwann was a German physiologist who defined the basic unit of animal tissue structure was the cell and helped begin the study of cell biology. He proved the cellular origin of fingernails, tooth enamel, and feathers. He also discovered the digestive enzyme pepsin and coined the term ‘metabolism’ to describe the chemical reactions in living organisms necessary to stay alive.