6/29/1818 Pietro Angelo Secchi, astronomer, pioneer in astronomical spectroscopy, he was the first person to state that the sun was a star. He died in 1878 at the age of 59, he did so many other things for astronomy he is worth looking up.
6/29/1833 Peter Waage, chemist, co-discovered the law of mass action with his brother-in-law Cato Guldberg, he died in 1900 at age 66.
6/29/1868 George Hale astronomer, invented the spectroheliograph, suffering from frequent insomnia and schizophrenia, he claimed to have regular visits from an elf who advised him, he died in 1938 at age 69. Quote: “Like buried treasures, the outposts of the universe have beckoned to the adventurous from immemorial times…”