International Operations works with the Department of Homeland Security and other U.S. agencies to vet participants in International Visitors Program events nationwide.
Life cycle. Life cycle means the stages a living thing goes through during its life. In some cases the process is slow, and the changes are gradual. Humans have various steps during their lives, such as zygote, embryo, child and adult. The change from child to adult is slow and continuous.
The life cycle of a star, from birth in a dense interstellar cloud to its final end, is a process that lasts anywhere from a few Million years for the most massive stars to many Billions of years for stars like the Sun.