All the material galaxies floating in the space of the material cosmos have a beginning, and will all, at a date known only to God, come to an end, when they will be destroyed. Before that, all beings will die: the celestial beings living on the galaxy's higher planets, human beings, terrestrial and aquatic animals, and every plant from a blade of grass to a large tree. Souls will be extracted from their respective bodies by Krishna's celestial attendants and will then enter the Lord's body, where they will be plunged into a deep sleep. After a period of non-existence, or non-manifestation, Krishna will recreate the galaxy identically, and all souls will reincarnate in the same type of body they were in during the previous creation.
What is death?
The material universe in which man evolves is the world of forgetfulness, suffering, and death.
Death is being plunged into forgetfulness and ignorance of all the facts relating to Krishna, God, the Supreme Personality of Godhead, as He truly is, as well as all His exceptional divine qualities, glories, excellences, and sublime pastimes.
Death is being separated and estranged from Krishna, God, the Supreme Personality of Godhead, and no longer knowing anything about Him or how to find Him.
Death is the loss of the natural position of eternal servants that we occupied before Krishna, no longer being able to offer Him our spiritual services, and no longer being able to act for Him with joy. Death is the loss of the bond that united us to God, and of the loving relationship we shared with Him at the beginning of all things.
Death is being plunged into forgetfulness and ignorance of all the data relating to our true spiritual identity, of existential and absolute truth, of the spiritual teachings of which Krishna is the divine author, and of the existence of the spiritual world.
Death is being plunged into forgetfulness of our true spiritual origin, and no longer knowing that we all come from the true world, the spiritual world.
Death is no longer knowing anything about our past, and all our different previous incarnations.
Death is the change of body, for it is the body of dense matter in which we are incarnated that plunges the soul into forgetfulness of everything.
All those who understand these truths will see their existence change. Lord Krishna, by His divine grace, will put an end to all their suffering. They will pass from death to eternal life, for them there will be no more death.
The condition of the eternal soul that each of us actually is, for we are not the dense material body in which we incarnate, is due to our ignorance of spiritual data. Although life is temporary, it is nonetheless undesirable, for this material world is in reality the world of forgetfulness, suffering, and death.