Someone should be watching the sky

We have a Space Force now. But thinking about it more, Space Force is essentially about military operations in near-Earth space - satellites, orbital positioning, that kind of thing. It is not really about threats from outside. So who is responsible for protecting Earth from an actual extraterrestrial threat? An asteroid, a large impactor, something on a collision course?

I went looking and found that NASA has a Planetary Defense Coordination Office. Spaceguard has catalogued most large near-Earth objects. That is something. But then I came across Chelyabinsk.

February 15, 2013. The Chelyabinsk meteor, about 20 meters across, entered the atmosphere over Russia. Nobody saw it coming - it approached from the sun's direction, which put it outside the field of view of every ground-based survey at the time. It detonated with roughly 30 times the energy of the Hiroshima bomb, injured nearly 1,500 people from the shockwave alone, and shattered windows across an entire city.

That was 20 meters. Undetected.

The asteroid that ended the Cretaceous was about 10 kilometers across.

So I started asking - do we actually have the technology to deal with this? And the answer is yes, the pieces exist. Infrared space telescopes can detect objects approaching from the sun's direction. NASA's DART mission in 2022 proved kinetic impactors work - they crashed a spacecraft into a small moonlet called Dimorphos and measurably changed its orbit. Laser ablation can nudge smaller objects over long timeframes. For large objects with limited warning, nuclear standoff detonation - detonating a warhead near but not on the object to create a thrust impulse - is the serious option and the physics has been studied.

The technology is not the problem. So what is?

Any system capable of deflecting an asteroid is also a weapon. A laser that nudges a rock away from Earth can nudge one toward it. A kinetic impactor built for defense is an offensive capability. You cannot separate these at the engineering level. So if one nation builds a serious planetary defense system, every other nation has reason to be concerned about what else it could do.

This is why a company is the wrong answer even though it is the obvious first instinct. A company has a jurisdiction, shareholders, and an exit option. What is needed is something structured more like CERN - an international institution, member states, shared infrastructure, shared detection data, transparent operations, no single nation controlling the response capability. The benefit is all of humanity and the institution needs to reflect that.

The reason this does not exist at the level it should comes down to something predictable. Humans are bad at low-probability high-consequence risks when the time horizon is long. We fund cancer research because we know people with cancer. We do not fund planetary defense seriously because nobody in living memory has died from an impact. The last civilization-scale event was 66 million years ago. That distance makes the risk feel abstract even when the math says it should not.

An extinction-level impact is low probability in any given century but near-certain over geological time, and the consequence is everything. That asymmetry should be obvious. The technology is ready. The physics is solved. The only thing missing is the institutional will to treat this like the civilizational risk it actually is.

Someone should build that institution.