Today, Nasa's Cassini spacecraft will point itself toward the surface of Saturn, and end with a crash its 13-year mission delving into the mysteries of the ringed planet's system.
Cassini's instruments have revealed new details including the only extra-terrestrial lakes known in the solar system, and its final series of orbits will reveal details of the interior structure of Saturn, as well as provide unprecedented views of the rings.
In celebration of the end of the Cassini mission, and all it has shown us about the Saturn system, IOP Publishing is making the ebook The Ringed Planet by Dr Joshua Colwell free to download and read for 30 days.
The Ringed Planet is a dramatic, beautifully illustrated journey of discovery through the Saturn system. It explores and explains the fundamental processes that shape not just the Saturn system, but planets and moons in general.
Written for the general audience with an emphasis on the fundamental physics of planetary systems, it places Saturn in the context of the whole solar system.
John Navas, senior commissioning manager for ebooks at IOP Publishing, said: "The end of the Cassini missions is one of the most significant events in astronomy and planetary science for some years. We're extremely proud to be able to offer The Ringed Planet for free, to enable as many people as possible access this important and fascinating scientific knowledge."
The author, Dr Joshua Colwell, is a planetary scientist and professor of physics at the University of Central Florida. He is a co-investigator on the ultraviolet imaging spectrograph on the Cassini mission, and his research interests are in the origin and evolution of the solar system with a focus on planet formation, planetary rings and interplanetary dust.
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