Galileo's Daughter (1999)
The eldest daughter of Galileo Galelei was a nun who remained in contact with her father through letters her entire life. Although Galileo's letter to her were destroyed after her death her letters to him were, for the most part, remain and were the basis for this book. If you're looking for a new non-fiction book, I'd recommend this.
The Planets (2005)
The Planets looks at–unsurprisingly–the planets. Including (since it was published in 2005) Pluto. Although as a whole I thoroughly enjoyed it, there were some chapters I like better than others.
The chapters are dedicated to different planets, as well as a chapter on the sun/start of our solar system as well as a chapter for the moon. Each chapter looks at the planet in question in a different manner. I particularly liked the chapter on Neptune and Uranus, which includes a letter from Caroline Herschel to Maria Mitchell and the chapter on the moon, which looks not just at the moon but how the moon affects the earth and those of us on the earth.
I did not, however, like the tack she took with Mars, where the chapter was written from the point of view of a rock that was thrown from mars and eventually landed on Earth. And I wasn’t enamored of all the astrology that filled the chapter Jupiter.
All in all it was an interesting book, and I did learn lots of interesting facts about the various planets, but all in all I much preferred Galileo’s Daughter.