1) The Dow Jones Industrial Average (DJIA) is a stock market index that tracks the performance of 30 large, publicly owned companies in the United States.

2) The first photograph of a black hole was captured in 2019 using a network of telescopes around the world.

3) The world's oldest tree is believed to be a bristlecone pine named "Methuselah" in California, estimated to be over 4,800 years old.

4) Marilyn Monroe, born Norma Jeane Mortenson, was an iconic American actress, model, and singer, known for her beauty, charisma, and tragic personal life.