The universe began with an explosion that still reverberates after around 15 billion years—called the Big Bang. Since that time, stars and come and gone in bursts of energy and if we were to sample space outside our little bubble of atmosphere, both in the solar system and in interstellar space, we’d experience massive radiation.
The sun, in some way, protects us from cosmic particles of very high energy—the solar wind and the sun’s magnetic field acts as a shield with a kind of barrier called the heliopause, well past the orbits of the ordinary planets. Of course the sun also produces outbursts of radiation—solar wind is an example of this.
In addition to this normal, everyday threat, we also have black holes, supernovas, and something called a hyper-nova (or collapsar), where a rotating star of 30 solar masses (or larger) exhausts its normal fuel and produces a truly massive outburst of gamma radiation along two cone angles alined with the axis of rotation, producing blasts of energy second only to the big bang itself. If the Earth were to be within this cone angle of a start within a thousand light years of Earth, all (or most) life on our home world would be fried.
To this, add the strange nature of our solar system, and the asteroids, comets, and even potentially rogue super planets wandering thorough the galaxy, any of which could, and eventually will, impact the earth. Other forces, like super volcano eruptions, don’t even register on these scales of energy—although if Yellowstone volcano were to erupt, it would mean an end to the United States.
While we ponder expending all of our human energies to combat what may be a phantom threat like global warming, remember that humans have survived, thus far, by adapting to changes, not trying to control what cannot be controlled. If all of our own energies are expended on such futile attempts, we will have nothing with which to respond to real threats.
Ponder this as people tell us that we must all sacrifice everything we have and give control of our resources (and surrender our liberties) to these doomsayers—only the latest in a series of doomsayers demanding absolute power over us all, from witch doctors who warned about how angry the spirits would be if we didn’t obey them, to those predicting mass global starvation in the 20th century from overpopulation, to predictions of the coming ice age in the 1970’s. There are always those who demand tribute and absolute obedience from everyone, but in the grand scheme of things these charlatans come and go with regularity, just as eventually we will all depart this violent, chaotic universe.