The cosmos is dangerous for earth. From asteroid strikes, supernova explosions and gamma-ray bursts it can be life-ending. The article provides examples of each of these in earth's history.
Hubble can help us detect and learn about these dangers, but ultimately if humans don't want to go the way of the dinosaurs we need to become a multi-planetary species.
The cosmos can kill us in many ways. But the James Webb Space Telescope can help save us
A fateful asteroid caused the demise of the (non-avian) dinosaurs 65 million years ago. But that wasn’t an isolated event. Many of the mass extinctions in our planet’s past were caused by meteorite impacts, and it remains a clear and present danger today. In 2013, the Chelyabinsk meteoroid, as big as a six-story building, broke up over Russia and produced a blast stronger than a nuclear explosion. Only a century earlier, the Tunguska meteoroid exploded over Siberia, flattening 80 million trees over an area of 2,150 square kilometers.
]The largest impact event in Earth’s history occurred shortly after our planet formed, when it collided with a Mars-sized planetary body. That resulted in the creation of Earth´s Moon and long-lasting magma oceans on the surface, which made our planet uninhabitable for some time.
Cosmic killers
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James Webb Space Telescope to the rescue
Now, the good news. The recently launched James Webb Space Telescope (JWST) may help us recognize some of these cosmic threats ahead of time. One of the main goals of JWST is to image planets around other stars, but it also will be able to observe small bodies such as asteroids and comets in our own solar system. Even while it was still in its commissioning period, the telescope tracked an asteroid (Tenzing 6841) — the first time a space observatory has been able to do so.
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The ultimate solution to these cosmic threats, if we want to survive into the far future, is to become a multi-planetary species. In the meantime, let’s at least keep watch for any dangers looming out there. We do not want to end up like the dinosaurs.