Scientists demonstrate X-rays as a way to zap asteroids out of Earth's path US scientists have demonstrated that potentially dangerous asteroids destined for Earth could be deflected from their trajectory using X-rays. The researchers said the technique, which involves using a powerful X-ray pulse to vaporize a chunk of the asteroid's surface, could potentially be used for future planetary defense …
The 5MT warhead for the Spartan ABM was designed to maximize X-ray output. Seems to me that would be a good start for any asteroid deflecting nuke.
The X-rays would be mostly absorbed near the surface and thus vaporizing a layer of the surface facing the nuke. One question in my mind is whether the rubble pile construction of many asteroids would hold together if the nuke was close enough.
According to The Guardian it was a simulation of the effect a nuclear detonation would have on an asteroid:
"Physicists at Sandia National Laboratories, whose primary mission is to ensure the safety and security of the US nuclear arsenal, recorded in nanosecond detail how an immense pulse of radiation unleashed by a nuclear blast could vaporise the side of a nearby asteroid."
https://www.theguardian.com/science/2024/sep/23/nuclear-blast-could-save-earth-from-large-asteroid
So, no shark mounted X-Ray Space laser required.
I'm guessing that the reference to the Earth being poorly prepared for a potential extinction level asteroid impact is an assessment of current technological capabilities and the absence of any coherent actual ability to, well, 'nuke an asteroid'.
*Sorry, couldn't resist the reference to 'Apocalypse Now', or the nuclear bomb explosion icon.
Looking at the history of our planet being hit by asteroids ever since we upgraded from just being a ball of ice in space makes me wonder how much (or how little) chance there is of highly intelligent life in the universe - I think we have the possibility of being unique but there's no evidence yet.
Our human history started after the most recent huge asteroid strike that eliminated the dinosaurs 66 million years ago, once situation of "life" improved after that strike then life started again when some surviving fish started to walk out of the sea onto the empty land that eventually became so many different lands around the world, not just the one original big island. So in the universe asteroid strikes may remove life but it seems that we were created on our world after a strike.
All efforts to prevent dangerous strikes in the future are very good - potentially encouraging the survival of our intelligent life in the universe.
I suspect you need to revise your history of Earth, life didn't have to start again from fishes after the Cretaceous die-off, not even after the Permian event.
But if all land-based life was killed off a few hundred million years could see some sort of intelligent life on this planet. Less likely things have happened, apparently.
The hit that did it for the big dinosaurs was not a global total extinction event, small dinosaurs and mammals survived and once the air had cleared a bit thrived in a environment free of large predators. There was no need to wait for fish to evolve into land dwellers again.
Mammals rapidly diversified and filled the gaps left by the demise of the big dinosaurs. The remaining dinosaurs evolved slower than mammals so they could only exploit the remaining gaps evolving into the birds we know today.
(This is all a gross over-simplification but the general argument is correct)
The potential for the creation of human land dwellers is well described in the book "Your Inner Fish: A Journey into the 3.5-Billion-Year History of the Human Body" written by Neil Shubin. He's just describing our creation but after reading it originally, I spent years researching the bone structure of all land animals related to fish ... they are all distantly related, not identical but very similar. We are like monkeys but also cats, dogs, cows, lions, horses, squirrels and even birds - vast differences but suggestions that one environment created almost all life. Insects are completely different but all appear to have their own relationships - such a different form of creation.
If any of this makes you wonder what happened then reading Neil Shubin's work will help you.
The "history" is just what we guess after looking at fossils, our "records" are just how we see what did happen and try to think about the results - no "full evidence" only just guesswork. I think that the existence of crocs and gators is a very good suggestion that so much life in the water may have extending our life after the strike ... and the bone structure of the crocs, gators, and the dinosaurs, compared to us suggests that fish are our ancient ancestors. I suspect, based on our history that life in the universe probably all starts in the water throughout the universe.
In the same way that there is no “full evidence” that the Earth and other planets came from an accretion disk around the nascent star we call the Sun.
We just look at what’s here now, and “guess” that’s what happened.
Glad you understand what science is… weird place to push this. Must be a bot…
"The researchers said future experiments could investigate other target materials and structures and test different X-ray pulses since the vapor plume generated by the X-ray pulses is dependent on the chemical composition of the asteroid."
If they were concerned about that why not use something a bit more dissimilar to quartz than fused silica?
Too bad the efforts to work out what to do about them have not.
BTW there have been at least 5 events that have wiped out >70% of all life forms in several layers of the fossil record
Sorry, but the Earth won't miss us if anything happened to the human race.
"Low level efforts to identify killer asteroids have worked quite well.."
Fortunately, Musk, and his peers are doing their best to ensure we can't spot approaching killer asteroids. So we will remain blissfully ignorant until the impact.
The oldest fossil is, what, 3.5bn years old? So 5 civilisation-destroying events in 3.5bn means they're probably not around the corner and we've probably got a few years to get our act together. Worry more about smaller objects, that are harder to see, but could do real damage if they landed on a metropolitan area.
2 obvious reasons
1) Keeping the beam tight, possibly including issues with thermal atmospheric blooming.
2) Providing sufficient energy in the beam ("22 MJ of stored energy into an electric current pulse"), does not describe how much energy was in the actual beam. At physically larger sizes initial bloom from the target will tend to prevent the beam hitting the solid target beneath the vapourised material. I would like to see some scaling evaluations, not just small scale testing.
I was thinking perhaps we miss interpreted the article. A 15cm sphere would need close on double the power, no problem but a proper sized asteroid say 12 meters diameter would need 1000000 times more power than the largest pulsed power device in the world today. I am still checking the calculations to get the final laser link budget from the moons surface to an asteroid 250,000 km away. I think they are going to need some very very large capacitors to due this.Very large everything. Perhaps this is all just Pi in the sky.
The first issue is being able to find an asteroid far enough out that there's a possibility that squirting some light on it will deflect it enough for a miss. Comets have a nice high albedo, but an Iron-Nickel asteroid can be very dark and hard to detect until it's quite close. A good detection system is an equally high priority.
"According to some documentary I've watched recently ("Don't look up"), wouldn't it be, say, for example, Elon Musk's job to take care of such threats?"
Well, maybe, but his rockets will need to get much higher up before they go boom and they'd need to be on target as well.
Said a nuclear bomb on the surface wouldn't do it.
Needed 2 bombs. One to make a crater, second to go deep enough inside a planet killer to split it into small enough chunks that would either miss earth or burn up.
And of course it would be all about where those "small" chunks land.
Tunguska was roughly 70 Mt. It was less than 10m across. No fission involved.
One of those in the "wrong" part of the ocean and that's a 20m high wall of water hitting New York City*
*Other major cities that would be devastated/completely destroyed are available.
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