I think our present space technology research focus should be on these asteroids. Both how to deflect them (peacefully) and how to mine them for rare metals.
If I read this table correctly it seems that only eight days ago a fairly chunky rock passed within 60,000 miles of us:
Really cool link, thank you. I think you are referring to the 2017 QP1 asteroid that was closest to us on 14-Aug. the distance was about a sixth of the distance to the moon, or 38k miles. The speed was 24km/s and the diameter 37-83 meters. Just for fun I ran the Impact Earth calculator to see what would happed if such an asteroid hit Earth. Assuming the worst case scenario (iron meteorite, max diameter, perpendicular hit) the explosion would be equivalent to about 200 MT TNT, and the crater would have a 2 mile diameter and 2000 foot depth.
Speed values in space always seem to omit "relative to what" clarifications. Relative to the earth, the sun, along the earth's orbital path or contra, etc.? It makes a huge difference.
Well, in >4 bn years there have been probably less than 5 such events. Catastrophic yes, but very low possibility. I can understand if any agency even the slightest related to space prioritizes other things.
As far as my understanding goes, space is very unevenly distributed, with lots of debris and asteroids in dense (well, humpf) parts of space, but the vast majority of it is just... empty space with so little matter in between that it is basically negligible. To mine an asteroid likely means going to where it's more probable to find a suitable one, and also more risky. Asteroids around us are few (IIUC).
Death by asteroids is a low risk but high impact type of event. We cannot afford to have even one such event.
It really does only take one and costs little for us to prepare. We want to mine asteroids and further science anyway, so we are going up there already. It's not like the cost of the whole space program is dedicated to defending from this. We just need to have a few plans ready to go when we do find it.
It would cost millions of dollars, compared to the billions already in space and trillions we spend in defense. What is money in the face of a 0.00001% chance of annihilation?
> What is money in the face of a 0.00001% chance of annihilation?
Every day that you commute to work, you have a higher then 0.00001% chance of dying in a traffic accident.
Yet, you still roll the dice, and go to work. Presumably because you get paid.
For a more global catastrophic event, consider that the odds that you will die in a catastrophic nuclear war between Russia and the United States are far, far greater then 0.00001%. Yet, we all carry on as if its business as usual. (When we could take steps to reduce how catastrophic such a war would be, or how likely such a war would be.)
I think you've just pointed out the fallacy here: the false equivalence of a risk affecting one person vs. the entire human race (or planet).
The if the odds of dying in an auto accident for one person are 0.00001%, then the risks of the 7.5 billion souls on this rock dying simultaneously in an auto accident are 0.00001% raised to the power of 7.5 billion. That's basically 1 * 10^-45% odds.
The comparative risk posed by the asteroid is approximately 1 * 10^40 times greater.
Each of us may face that risk, but all off us don't, together.
This is a point at which conventional models of risk start falling apart. There's a meaningful difference between small events randomly distributed, and massive large impacts occurring everywhere all at once. Also between small events with no interconnectedness, and with systemic failure.
Simple incident occurrence rate fails to capture this.
We also invest heavily in preventing such a nuclear exchange.
Of course we continue on, we hope or expect that we will still be here. Rather than just lob missiles or give up, we took a stance and many active and expensive steps costing the equivalent of trillions of modern dollars. We definitely took real action on the Threat of Nuclear war.
We also invest incredibly heavily into making such a nuclear exchange more likely. We've sunk trillions of dollars into building a collective suicide switch.
We don't need more then a hundred nuclear weapons for MAD to work. Meanwhile, Russia and the US are pointing thousands of them at each-other. (And in the US, at least, the minimum number of people required to authorize a launch is tragically small. In a time of escalated tensions, a president can bring about the end of the world, without the consent of anyone else. There is no law or military process that can prevent it.)
Even if the odds of nuclear war were 1% in my lifetime, it would be an unacceptable level of risk. I wouldn't be surprised if it is, in reality, much higher.
>Death by asteroids is a low risk but high impact type of event. We cannot afford to have even one such event.
Depending on how rare and difficult to tackle would be, we probably also cannot afford to do anything about it.
If we have as much as 1% or even 0.1% possibility of one hitting earth in the next 100 years, we would have rallied to build something even if is very costly and difficult.
In 0.00001% chances or less, there's no way any country is gonna's devote any significant resources...
>What is money in the face of a 0.00001% chance of annihilation?
Still very important?
(We have a much more concrete and possible chance of billions of deaths from nuclear arms and/or global warming, but we still don't do anything about it).
Spending in one area does not prevent spending in another. we have many dollars and some problems require more than others. They can even work together, perhaps a tax on CO2 release can fund diplomatic and scientific missions to help mitigate or prevent the other two catastrophes.
> As far as my understanding goes, space is very unevenly distributed, with lots of debris and asteroids in dense (well, humpf) parts of space, but the vast majority of it is just... empty
Even the "asteroid belt" is really empty. It's not like you see in science fiction movies where asteroids are hitting into one another continually.
The ability to deflect asteroids away from Earth also means you can deflect them toward Earth and even aim them at your enemies! You could sneakily aim a meteor strike at anywhere on Earth and make it look like a natural event.
Technically this is something that could be done today with gravity tractor [0] or an ion beam deflection [1] system, both of which are being developed by NASA.
> You could sneakily aim a meteor strike at anywhere on Earth
Can you? Are you sure? My understanding is that it's not possible to predict the trajectory at less than the size of a continent. Much less actually control it.
Well it just so happens that the 3 countries where this would be seen as favorable attack vector against the others happen to be the size of continents. Mainly China, Russia, and The USA.
In principle it's no different from predicting the path of a spaceship, which can be done with great accuracy. The error comes from imprecision in knowledge of the meteor's location and velocity, which would improve greatly once you start pushing it around.
And in fact, the path of an unguided spaceship can not be predicted. Go look for old news stories of satellites crash landing - they can only give general areas, not exact.
That's a completely different scenario. Satellites in decaying orbits are descending due to atmospheric drag. Atmospheric drag is difficult to predict because it depends on the precise shape of the satellite, the precise orientation, and atmospheric conditions at each moment.
If you're dropping an interplanetary asteroid on an enemy, it won't be in a slowly decaying orbit. It'll spend a few seconds within the atmosphere, which won't mess up predictions that much.
It occurs to me that we just had a great example of the ability to predict where big rocks will be in space long in advance. People were able to predict that the Moon's shadow would cross from Oregon to South Carolina decades ago, and of course the predictions were spot on.
You underestimate the difficulty. For example the asteroid could break up, which would move the trajectory. If the asteroid is not round it will tumble and shift. Uneven heating would cause a "jet" of hot air to act like a rocket and move the asteroid.
Don't forget that it's very unlikely you will be able to guide an asteroid perpendicular to the earth (which would give you the most accuracy, and the most velocity, which also helps with accuracy). Most of the asteroids obit more or less in the same plane as the earth, so you will have to settle for a more shallow impact, which will magnify atmospheric effects.
> example ... moon
We have had thousands of years to precisely record the orbits of the moon and earth [sun]. That is the only reason we are able to predict it. And despite that, past a few hundred years accuracy goes down, and past 1 thousand or so it's mostly impossible to predict eclipses.
And that's for bodies we have very accurate data on, and who have no atmospheric drag.
The inaccuracy for eclipses is because we can't predict how fast the earth will turn (to an accuracy of a ppm) more than a few months out, and because of tidal effects changing the orbit of the moon.
Small asteroids have a very small escape velocity, on the order of a few meters per second. I think a mass driver which broke off small chunks of asteroid and hurled them to escape would not take too much power and be able to disassemble the asteroid in less than one orbit. (Advanced detection would be a plus here.) If we aimed the ejecta, to get a momentum change in a given direction, we would not have to completely disassemble the asteroid, because its orbit would change and eventually miss Earth. Complete disassembly would be safer, because small chunks would burn up in Earth's atmosphere.
If I read this table correctly it seems that only eight days ago a fairly chunky rock passed within 60,000 miles of us:
https://cneos.jpl.nasa.gov/ca/