Ultra-rare star collision in Milky Way could wipe out life on Earth, study finds

A new study has found that an ultra-rare star collision in the Milky Way galaxy could wipe out life on Earth. The study, published in the preprint server arXiv, found that a collision between two neutron stars, known as a kilonova, could produce a burst of gamma radiation that could strip away Earth's ozone layer and induce a mass extinction.

Neutron stars are the densest objects in the universe, formed when massive stars collapse at the end of their lives. They are typically about the size of a city, but with the mass of the sun. When two neutron stars collide, they produce a kilonova, which is one of the most energetic events in the universe.

Kilonovas are so rare that astronomers have only observed a handful of them so far. However, the new study found that even if a kilonova occurs within a few hundred light-years of Earth, it could still pose a serious threat to life on our planet.

The study's authors used data from the first-ever detected kilonova, GW170817, to model the effects of such an event on Earth. They found that if a kilonova occurred within 297 light-years of Earth, it could produce a burst of gamma radiation that would be powerful enough to strip away the ozone layer.

The ozone layer protects life on Earth from harmful ultraviolet radiation from the sun. If the ozone layer were destroyed, it would expose life on Earth to high levels of UV radiation, which can cause cancer, cataracts, and other health problems. It could also damage plants and animals, disrupting the food chain.

The study's authors also found that the kilonova could produce a blast of neutrons that could damage DNA and cause mutations. This could lead to an increase in cancer rates and other genetic diseases.

The good news is that kilonovas are extremely rare. The study's authors estimate that a kilonova could occur within 297 light-years of Earth once every 100 billion years. However, even though this is a very rare event, it is important to be aware of the potential risks.

What can we do?

There is no way to prevent a kilonova from happening. However, there are some things we can do to mitigate the risks to life on Earth.

One important step is to develop better early warning systems for kilonovas. This would give us more time to prepare for the event and to take steps to protect ourselves.

We could also develop technologies to repair the ozone layer if it is damaged. For example, we could use lasers to create artificial ozone molecules.

Finally, we could also develop ways to protect ourselves from the harmful effects of UV radiation and neutron bombardment. For example, we could develop new types of sunscreen and clothing that can block UV radiation. We could also develop drugs that can protect against DNA damage.

Additional thoughts

In addition to the potential risks to life on Earth, a kilonova could also have other negative effects. For example, it could disrupt our communications and power systems. It could also damage satellites and other spacecraft.

Overall, the study's findings highlight the importance of space exploration and research. By learning more about the universe and the potential threats that exist, we can better prepare ourselves to protect ourselves and our planet.


The study's findings are a sobering reminder of the potential dangers that exist in the universe. Even though a kilonova is a very rare event, it is important to be aware of the risks and to take steps to mitigate them.