Final answer:
There are nine justices on the Supreme Court, which includes one chief justice and eight associate justices, a number that has been in place since 1869.
Step-by-step explanation:
The question of how many justices are on the Supreme Court can be answered by looking at its history and the current established number. Originally, the court in 1789 consisted of six justices, but this number has fluctuated over time due to different legislative actions. By 1869, Congress set the number at nine, which includes one chief justice and eight associate justices. This structure continues up to the present. The justices are appointed for life, pending nomination by the president and confirmation by the Senate. The Supreme Court is the highest court in the United States, with its decisions being binding on all other courts within the federal system.