Np-237, or Neptunium-237, is a radioactive isotope of the element neptunium. It has a half-life of about 2.14 million years, making it one of the more stable isotopes of neptunium. Np-237 is produced in nuclear reactors and during the decay of plutonium and uranium. It is primarily used in research and has potential applications in nuclear batteries. Due to its long half-life, Np-237 poses challenges for waste management in nuclear facilities. It emits alpha particles and has a low level of gamma radiation, which requires careful handling and storage to ensure safety.