List of Famous people born on September 9th

Heinrich Johann Welker was a German theoretical and applied physicist who invented the "transistron", a transistor made at Westinghouse independently of the first successful transistor made at Bell Laboratories. He did fundamental work in III-V compound semiconductors, and paved the way for microwave semiconductor elements and laser diodes.

Anatoly Pavlovich Artsebarsky is a former Soviet cosmonaut.

Matti Rönkä is a Finnish TV journalist and novelist. He received the Glass Key award in 2007 for the crime novel Ystävät kaukana and the Deutscher Krimi Preis third prize in 2008 for the German translation of his novel Tappajan näköinen mies (2002). He has been the anchor of the daily news program 20:30 National Report since 2003 on Yle, thus inheriting the nickname "Suomen ääni" from the program's old host Arvi Lind.

Pierre-Laurent Aimard is a French pianist.

Helen Fay Dowker is a British physicist who is a current professor of theoretical physics at Imperial College London.

Arthur James Plunkett, 8th Earl of Fingall KP , styled Lord Killeen until 1793, was an Irish peer. A prominent Roman Catholic, he was a leading supporter of the cause of Catholic Emancipation. He was at the same time a loyalist who played a leading role in suppressing the Rebellion of 1798.