When stars run out of hydrogen they die in a massive explosion known as a supernova. However, a new phenomenon has caused the science community to reconsider what a supernova really is.

A recently discovered star named iPTF14hls was found by the Intermediate Palomar Transient Factory in 2014. This abnormal star has been referred to as the “zombie star” by many news articles, and has caught the attention of scientists and journalists around the world.

At first, the supernova appeared to be a ordinary type II supernova, caused by the rapid collapse and violent explosion of a massive star. It was expected that the star would dim in about 100 days. Weeks later, a light from the location of the supernova began to glow brighter. After 600 days of observation the star had remained bright, rather than cooling down with time as expected of a Type II. The star continued to explode for six times while its time under surveillance. The star also remained at a near-constant temperature of about 5,000–6,000 degrees celsius. These amazing irregularities are far different than what normally occurs inside a star.

Stars are generated from clouds of gas and dust called nebulae. The hydrogen obtained from these nebulae generate energy for the star’s lifetime, until it runs out. Once it is all used, the star will expand and cool into a red giant or supergiant. If a star has a normal mass, it will later become a white dwarf. On the other hand, if the star has a large mass then it will explode and create a supernova that leaves a neutron star, and possibly a black hole if it is massive enough.

NASA defines a “supernova” as “a large explosion that takes place at the end of a star’s life cycle.” Because of the amazing new information and theories that could arise from this new phenomenon, it’s possible that scientists will change this definition once the root cause of the unnatural event is found and researched.