How many moons does Mars have?
Mars has two moons, they were named Phobos and Deimos by the American astronomer Asaph Hall, who discovered them in August 1877.
### Instruction: How many moons does Mars have?
### Context: 
### Answer: Mars has two moons, they were named Phobos and Deimos by the American astronomer Asaph Hall, who discovered them in August 1877.</s>