Aristid von Grosse was a German

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 nuclear chemist. During his work with Otto Hahn

Otto Hahn

Otto Hahn FRS was a German chemist and Nobel laureate, a pioneer in the fields of radioactivity and radiochemistry. He is regarded as "the father of nuclear chemistry". Hahn was a courageous opposer of Jewish persecution by the Nazis and after World War II he became a passionate campaigner...

, he got access to waste material from radium

Radium

Radium is a chemical element with atomic number 88, represented by the symbol Ra. Radium is an almost pure-white alkaline earth metal, but it readily oxidizes on exposure to air, becoming black in color. All isotopes of radium are highly radioactive, with the most stable isotope being radium-226,...

 production, and with this starting material he was able in 1927 to isolate protactinium oxide and was later able to produce metallic protactinium

Protactinium

Protactinium is a chemical element with the symbol Pa and atomic number 91. It is a dense, silvery-gray metal which readily reacts with oxygen, water vapor and inorganic acids. It forms various chemical compounds where protactinium is usually present in the oxidation state +5, but can also assume...

 by decomposition of protactinium iodide.

Aristid was born in Riga

Riga

Riga is the capital and largest city of Latvia. With 702,891 inhabitants Riga is the largest city of the Baltic states, one of the largest cities in Northern Europe and home to more than one third of Latvia's population. The city is an important seaport and a major industrial, commercial,...

 in January 1905. He died of pneumonia

Pneumonia

Pneumonia is an inflammatory condition of the lung—especially affecting the microscopic air sacs —associated with fever, chest symptoms, and a lack of air space on a chest X-ray. Pneumonia is typically caused by an infection but there are a number of other causes...

 in Laguna Hills, California

Laguna Hills, California

Laguna Hills is a city located in southern Orange County, California, United States. Its name refers to its proximity to Laguna Canyon and the much older Laguna Beach. Other newer cities nearby—Laguna Niguel and Laguna Woods—are similarly named.-Geography:...

on July 21, 1985.