Ytterbium-173 is a stable isotope of the element ytterbium, which has an atomic number of 70. It is one of the most abundant isotopes of ytterbium, making up about 16% of natural ytterbium. Ytterbium-173 has 103 neutrons and is used in various applications, including materials science and nuclear research. This isotope is notable for its unique properties, such as its ability to absorb and emit light, which makes it useful in certain types of lasers. Additionally, ytterbium is often used in electronics and as a dopant in fiber optics, enhancing the performance of these technologies.