In this sequel to The Prisoner of Al-Hakim, Alhasan Ibn al-Haytham--mathematician, astronomer, and physicist of the Islamic Golden Age--continues his lifelong pursuit of knowledge, embarking on a daring journey with a new purpose. What begins with his curiosity about the green streaks that light up the sky leads him to The Empty Quarter in search of the fabled Crystal Oasis. Guided by Qur'anic verses and his relentless curiosity, Alhasan believes the site may hold the remnants of a fallen star.? While Alhasan chases after celestial mysteries and seeks the iron hidden in the earth, Sadeem, his newlywed wife, undertakes a journey of her own. Summoned by Governor Jalal al-Dawla, she introduces him to her husband's groundbreaking discoveries about light and vision. The Empty Quarter takes readers on two parallel adventures--one into the vast desert sands, the other into the halls of power. Both are filled with challenges, revelations, and the unyielding spirit of discovery that defined one of history's greatest scientific minds.