Buzz
This image, showing the X-ray afterglow from a gamma-ray burst, was captured by NASA's Chandra X-ray Observatory on July 12, 2001.
NASA/Getty ImagesIt’s unnerving to realize the countless ways natural global disasters could strike, potentially causing irreversible and catastrophic harm, even leading to extinction. While we face dangers like nuclear threats and human-driven climate change, these are the familiar risks. What about massive volcanic eruptions? Or wandering black holes?
Or consider the immense radiation that could be unleashed towards Earth if a star collapses, resulting in global annihilation?
The chances of that happening are extremely slim. But, we wouldn’t be doing our job if we didn’t mention that it’s technically possible, though it would require a series of incredibly unlikely events to line up. Consider yourself warned?
Here’s the deal with gamma-ray bursts: When a massive star collapses, it generates an enormous amount of radiation in tight beams. If one of these beams were to hit Earth, it could completely wipe out the ozone layer. Global cooling would follow, and acid rain would fall [source: Thomas]. It would not be a pleasant outcome for life on Earth.
The reality is that for a gamma-ray burst to destroy all of us, a lot of things would have to fall into place in an extraordinarily unlikely situation. For instance, the star would need to be close to Earth. Gamma-ray bursts are only expected to occur near Earth roughly once every billion years or so [source: Minard]. Additionally, the star would have to be perfectly aligned with us—otherwise, the radiation would miss us entirely, and we’d continue on polluting and fighting among ourselves.
That said, it’s not exactly reassuring to know that some scientists believe gamma rays may have contributed to the late Ordovician extinction about 440 million years ago [source: Melott]. Around 70 percent of marine life died off—keep in mind that nearly all life back then was marine [source: Minard]. The period shows signs of increased radiation, like global cooling, which may point to gamma-ray activity.
So yes, a gamma-ray burst could potentially wipe out life on Earth. It might have even happened before. But there’s no need to panic just yet—we still have about 500 million years before it becomes a genuine concern again.
