No, Stock Markets in the United States are closed on Martin Luther King Jr's Birthday, Monday, January 16, 2023
Martin Luther King Jr's Birthday is a US Federal Holiday. The holiday is observed on the third Monday in January. Martin Luther King Jr's actual birthday is January 15. The stock markets in the United States will be closed on this day, Monday, January 16, 2023. The US Markets will reopen on Tuesday, Jan. 17, 2023 with normal hours.
Source 1 - https://www.nyse.com/markets/hours-calendars