There seems to be a misunderstanding. Thomas Harriot was an English mathematician and astronomer, but he did not use a telescope to observe the moon. He lived from 1560 to 1621, and while telescopes were invented around that time, they were not widely used until later in the 17th century.

Galileo Galilei is credited with being the first person to use a telescope to observe the moon and make detailed drawings of its surface. He observed features like mountains, valleys, and craters in 1609.

So, while Thomas Harriot was a brilliant astronomer, he did not use a telescope to observe the moon's features.