The PDF of Galactic Astronomy is widely sought after for several practical reasons:
Often referred to as the "bible" of stellar dynamics, this text dives significantly deeper into potential theory, equilibria of stellar systems, and kinetic theory. While Binney & Merrifield balances observation and theory, Binney & Tremaine is purely theoretical. Final Thoughts
What are you researching? (e.g., stellar kinematics, spiral structure, dark matter) What is your current academic level ?
The book of the same name that James Binney wrote with Dimitri Mihalas in the 1980s. While the earlier work was a pillar of the field for its time, Binney and Merrifield's volume took full account of the extraordinary advances that occurred in the intervening decade, presenting a completely updated and expanded view of the subject.