Ernest Rutherford was a New Zealand-born British physicist who is often referred to as the "father of nuclear physics." He is best known for his discovery of the atomic nucleus and for his model of the atom, which proposed that the atom is mostly empty space with a small, dense nucleus at the center.

Rutherford conducted the famous gold foil experiment in 1911, in which he bombarded a thin sheet of gold foil with alpha particles. He expected the alpha particles to pass through the foil with minimal deflection, but to his surprise, some of the particles were deflected at large angles. This led him to conclude that the atom must have a small, positively charged nucleus at its center, surrounded by a cloud of negatively charged electrons.

Rutherford's model of the atom laid the foundation for our understanding of atomic structure and paved the way for further research into nuclear physics. His work also contributed to the development of the first nuclear weapons and nuclear energy.

In addition to his contributions to physics, Rutherford received numerous awards and honors throughout his career, including the Nobel Prize in Chemistry in 1908 for his investigations into the disintegration of the elements and the chemistry of radioactive substances. He was knighted in 1914 and became the first person to be elevated to the peerage as Lord Rutherford of Nelson in 1931.

Rutherford's work and legacy continue to be celebrated in the scientific community, and he is remembered as one of the greatest physicists of the 20th century.

One of his experimental observation was::: that some of the alpha particles bounced back or retraced the path back. moreover this was the observation that introduced the concept of the nucleus.