There’s that asteroid 2024 YR4 which currently has a 2% chance of hitting Earth in 2032.
Uh oh.
I kinda feel like… reading the socials… people are weirdly gleeful about the prospect?
It’s true, it is somehow comforting to contemplate the potential of the end of the world that at least isn’t my fault. It doesn’t make me feel like I’m complicit by not recycling a plastic bottle that one time or whatever. Like phew, I get to wallow in a guilt-free imminently immanentised eschaton.
And anything’s better than reading the news I suppose. If the bad guys win then yah-boo they’ve only got a few years to enjoy it. (You decide for yourself who the bad guys are.)
The asteroid is currently moving away from the Earth obliquely. Measurements of its trajectory are tricky so the impact probability keeps changing.
To track the latest odds, Danny O’Brien built are we doomed yet .org. Today it says:
The asteroid 2024 YR4 has a 1 in 47 chance of hitting Earth (2.1480%) on December 22, 2032.
(Here’s how he built the site including complete code.)
iPhone lock screen widget next pls. Give me my daily abyss gazing in perfectly typeset retina pixels.
2024 YR4 is 40 to 90 metres across.
Whereas: the asteroid responsible for the Tunguska Event, Siberia, 1905, is estimated at only 30 metres.
About that:
The airburst flattened tens of millions of trees over an area of about 800 square miles. Among the few eyewitness accounts there were reports of windows breaking and trees snapping 40 miles away.
(Paywall-busting link.)
Also from that retrospective:
The event also produced a nighttime glow in the sky that persisted for several days and could be seen across Europe and in Britain, about 3,000 miles from the site.
Clouds from comet water, apparently.
Note that the Tunguska Event did not leave an impact crater. Whatever it was exploded 3-6 miles up in the atmosphere.
According to the Earth Impact Database, there are only 190 confirmed impact structures.
Here’s an easy to read list of those impact structures, sorted by age (Wikipedia).
The most recent is from 1800 AD. Before that, 900 AD.
Asteroids are rare, you know, and erosion is fast on a geological timescale.
I couldn’t find a crater associated with the asteroid strike that destroyed Tall el-Hammam 3,600 years ago, potentially the source of the story of Biblical Sodom.
It was another air strike.
So it turns out 2024 YR4 is unlikely to hit the ground either.
According to Wikipedia:
Due to its stony composition, this would more likely produce a meteor air burst than an impact crater (for an impact on a continent) or tsunami (for an oceanic impact).
Phew but still not phew I guess? You probably still don’t want an air strike over a populated area. Ask the ancient Sodomites.
Wikipedia also shows a map of the risk corridor
– straight along the equator from Central America, across Central Africa, and into India.
And also the next date of closest approach: 17 December 2028.
I did read somewhere that, if you were to launch an asteroid deflection mission, the best time to deflect would be in 2028, because a small change could divert it a lot, rather than waiting till the cue ball has got us all lined up at the back-end of Q4 2032.
Three and a bit years!
One question for me is:
Who would pay for an asteroid diversion mission?
Like, the US has the space capability, but it’s central Africa or the Arabian peninsula that might get hit.
So is there a United Nations-run insurance system that we’re all paying into, and Nasa just draws down on that?
Or will there be some kind of negotiation where a bunch of countries get together and put out a Request for Proposals and the US and the EU and China bid to do the necessary and tack on a 10% profit margin?
We can’t even figure out who’s going to take the hit re the climate crisis.
The Nasa Sentry: Earth Impact Monitoring page for 2024 YR4, which has all the latest data, also introduced me to the Torino scale and the Palermo scale.
- The Torino Impact Hazard Scale is a 0 to 10 scale (with colour) for the “public communication” of potential Earth impact events. We’re currently at 3:
Attention by public and by public officials is merited if the encounter is less than a decade away.
- The Palermo scale is made for scientists, is a logarithmic scale, and has the handy property that
a rating of 0 means the hazard is equivalent to the background hazard.
Like, if the rating of a particular object is less than 0, then the impact is still less likely than something randomly appearing out of nowhere and hitting us within the same timeframe. 2024 YR4 has a Palermo rating of -0.34, i.e. don’t worry about it too much.
Oh yeah and also there would be 6 impacts. Huh.
I love a good scale. Here are some I collected before (2022).
And of course, check out micromorts (2020), a unit of risk defined as one-in-a-million chance of death.
Your background risk, simply being alive, is 24 micromorts/day; skydiving is 8 per jump; etc.
I feel like I need a calculator to convert between different risk scales.
Anyway so I don’t know what the state of the art in deflecting an asteroid is?
You could smash something into it?
Nasa’s DART mission crashed a spacecraft into the nearby asteroid Dimorphos (September 2022): Planetary defense test deflected an asteroid but unleashed a boulder swarm.
Ok maybe don’t do that.
You could paint one half white?
I ran across this paper: Asteroid control through surface restructuring (Ehresmann, October 2019) which summarises a few albedo-based approaches.
The idea is that you make one side of the asteroid more reflective than the other, then sunlight will push it away. Or radiating heat from a rotating body or something. Look I only took a year of astrophysics and it was a long time ago.
You can do this by either:
- White painting: i.e. you shoot paintballs at it.
- Laser ablation: an orbiting probe uses a high-powered laser to cut the asteroid surface into repeating sharp right triangles. The sawtooth surface has
angular dependent reflectivity
– it catches sunlight photons like a million tiny sails until slowly, slowly, one photon momentum exchange at a time, it steers the asteroid away.
Saving the planet by having a robot laser-carve 2024 Y4 into a deep space disco ball.
So, deflection in just under 4 years? Around the time of the next US presidential election. Not long.
The irony of all this would be if we’re able to reallocate sufficient global GDP for a rush mission to deflect a planet-killer asteroid in 2028 ONLY BECAUSE the world’s largest economy has been hijacked by a space-fixated profit-motivated hyper-authoritarian industrialist.
Don’t know about you but I’d take that as solid proof of interfering benevolent time travellers, nothing less.
There’s that asteroid 2024 YR4 which currently has a 2% chance of hitting Earth in 2032.
Uh oh.
I kinda feel like… reading the socials… people are weirdly gleeful about the prospect?
It’s true, it is somehow comforting to contemplate the potential of the end of the world that at least isn’t my fault. It doesn’t make me feel like I’m complicit by not recycling a plastic bottle that one time or whatever. Like phew, I get to wallow in a guilt-free imminently immanentised eschaton.
And anything’s better than reading the news I suppose. If the bad guys win then yah-boo they’ve only got a few years to enjoy it. (You decide for yourself who the bad guys are.)
The asteroid is currently moving away from the Earth obliquely. Measurements of its trajectory are tricky so the impact probability keeps changing.
To track the latest odds, Danny O’Brien built are we doomed yet .org. Today it says:
(Here’s how he built the site including complete code.)
iPhone lock screen widget next pls. Give me my daily abyss gazing in perfectly typeset retina pixels.
2024 YR4 is 40 to 90 metres across.
Whereas: the asteroid responsible for the Tunguska Event, Siberia, 1905, is estimated at only 30 metres.
About that:
(Paywall-busting link.)
Also from that retrospective:
Clouds from comet water, apparently.
Note that the Tunguska Event did not leave an impact crater. Whatever it was exploded 3-6 miles up in the atmosphere.
According to the Earth Impact Database, there are only 190 confirmed impact structures.
Here’s an easy to read list of those impact structures, sorted by age (Wikipedia).
The most recent is from 1800 AD. Before that, 900 AD.
Asteroids are rare, you know, and erosion is fast on a geological timescale.
I couldn’t find a crater associated with the asteroid strike that destroyed Tall el-Hammam 3,600 years ago, potentially the source of the story of Biblical Sodom.
It was another air strike.
So it turns out 2024 YR4 is unlikely to hit the ground either.
According to Wikipedia:
Phew but still not phew I guess? You probably still don’t want an air strike over a populated area. Ask the ancient Sodomites.
Wikipedia also shows a map of the – straight along the equator from Central America, across Central Africa, and into India.
And also the next date of closest approach: 17 December 2028.
I did read somewhere that, if you were to launch an asteroid deflection mission, the best time to deflect would be in 2028, because a small change could divert it a lot, rather than waiting till the cue ball has got us all lined up at the back-end of Q4 2032.
Three and a bit years!
One question for me is:
Who would pay for an asteroid diversion mission?
Like, the US has the space capability, but it’s central Africa or the Arabian peninsula that might get hit.
So is there a United Nations-run insurance system that we’re all paying into, and Nasa just draws down on that?
Or will there be some kind of negotiation where a bunch of countries get together and put out a Request for Proposals and the US and the EU and China bid to do the necessary and tack on a 10% profit margin?
We can’t even figure out who’s going to take the hit re the climate crisis.
The Nasa Sentry: Earth Impact Monitoring page for 2024 YR4, which has all the latest data, also introduced me to the Torino scale and the Palermo scale.
Oh yeah and also there would be 6 impacts. Huh.
I love a good scale. Here are some I collected before (2022).
And of course, check out micromorts (2020), Your background risk, simply being alive, is 24 micromorts/day; skydiving is 8 per jump; etc.
I feel like I need a calculator to convert between different risk scales.
Anyway so I don’t know what the state of the art in deflecting an asteroid is?
You could smash something into it?
Nasa’s DART mission crashed a spacecraft into the nearby asteroid Dimorphos (September 2022):
Ok maybe don’t do that.
You could paint one half white?
I ran across this paper: Asteroid control through surface restructuring (Ehresmann, October 2019) which summarises a few albedo-based approaches.
The idea is that you make one side of the asteroid more reflective than the other, then sunlight will push it away. Or radiating heat from a rotating body or something. Look I only took a year of astrophysics and it was a long time ago.
You can do this by either:
Saving the planet by having a robot laser-carve 2024 Y4 into a deep space disco ball.
So, deflection in just under 4 years? Around the time of the next US presidential election. Not long.
The irony of all this would be if we’re able to reallocate sufficient global GDP for a rush mission to deflect a planet-killer asteroid in 2028 ONLY BECAUSE the world’s largest economy has been hijacked by a space-fixated profit-motivated hyper-authoritarian industrialist.
Don’t know about you but I’d take that as solid proof of interfering benevolent time travellers, nothing less.