During the year following the publication of the Starry Messenger, Galileo was thrown into a maelstrom of argument, debate, and more discoveries. Those without principled reasons for opposing Galileo's discoveries were enchanted and began to imagine all kinds of new things. An English astronomer, Sir William Lower, who had been a student of Thomas Harriot's, reacted enthusiastically to Galileo's news. He wrote to Harriot on June 21, 1610, “We are here…on fire with these things.” For him, Galileo's discoveries were more startling than Magellan's trip around the world. He and Harriot both wondered whether the planets Saturn and Mars might have hitherto unseen moons revolving around them. They were right: both do have satellites, but they would not be found for many years.

Becoming Mathematician and Philosopher

Galileo now pressed forward with his plan to become mathematician and philosopher to the Grand Duke of Tuscany. With his new book of discoveries in hand and his improved occhiale, Galileo had much with which to impress the grand duke.