Your phrasing is rather sloppy and I have to guess what it is you are really asking, but nonetheless I have an answer. Radioactivity was first discovered by three scientists, Marie & Pierre Curie, and Antoine Becquerel. There are many ways to detect or observe radioactivity, but the simplest is that it affects photographic film as if it had been exposed. For a more sophisticated, modern observation, we use cloud chambers or bubble chambers.
The mass of the atom
Henri Becquerel was a French scientist who was credited for the discovery of radioactivity. He was credited in 1896.
History has no one credited with influencing Tesla to be a scientist.
Milo Farnsworth
James chadwick
Marie Curie
Marie Curie
Joseph Priestly was the scientist who is credited with much of the progress in the biological sciences during the 18th century. He is usually credited with discovering oxygen.
Chadwick and the neutronThomson and the electronrutherford and the proton
Europe is the country credited with discovering America.
one of the first antibiotics was actually discovered by a British scientist named Alexander Fleming. He is credited for discovering (penicillin)
radium
discovering
Issac Newton he identified the 3 laws (newtons Laws of psychics )that verified his thereum of Gravity , which later became a theory
Christopher Columbus was an early explorer. He is credited with discovering the Americas.
Euclid
I'm not exactly sure what you mean when you say "discovering." However, Alexander Graham Bell is credited for inventing it. -THE SMOKE LIVES