English mathematician, astronomer, and physicist Thomas Harriot (also given as Hariot) was born in Oxford, England, in 1560. He spent most of his life exploring the areas of science and math that fascinated him. In his early thirties he began working in astronomy. He calculated the distance between the celestial North Pole and the North Star by using a telescope and algebraic equations he had created himself. In 1607, Harriot made observations of Halley's comet with another homemade telescope. A few years later, he conducted detailed studies of Jupiter's moons and sunspots. Harriot was famous for not recording and publishing much of his work. One example of this pattern is that Harriot observed the moon with a telescope a few months before Italian astronomer Galileo Galilei did, but only Galileo charted the moon's features and performed followup studies. Galileo, therefore, received the credit for discovering that the moon had craters. Harriot, probably best known as a mathematician who derived a number of equations and notations that simplified algebra, died of cancer in 1621.