UK Emergency Alert

[podknocker]

If there was a massive rock heading our way, NASA and the ESA would be tracking it and would warn us.

They can track the larger ones, but there are many smaller ones out there and they can't be tracked so easily. We had 2023 DZ2 recently and we did get a bit of warning. Some turn up out of the blue, with little warning and we've been very lucky so far.

Something skimming along the atmosphere would probably bounce off, like a stone on a pond, but something falling at anything near vertical and the energy released would be huge. It's going to happen eventually. It only needs a weird gravitational change out there and our fate is sealed.

We could do with a SpaceX rocket full of nuclear warheads and that might knock the thing off course. Saying that, the latest launch doesn't fill me with confidence.

The only real threats I could imagine, are an attack from terrorists, or an escalation with the war in Europe. Putin starting a nuclear conflict would need an alert from the government, but I'm not sure what anyone could do about it, with the current ICBMs taking less than 2 minutes to reach our country.

 

[12th Monkey]

If there was a massive rock heading our way, NASA and the ESA would probably be tracking it and would warn us.

Amended! They definitely haven't tracked everything down yet. It seems counterintuitive that you read things along the lines of '90% of asteroids capable of causing global or local devastation have been located'. But the distribution of these objects seems to obey a power law, so if there's one at 1,000 km across, there will be 10 at 100km across, 100 at 10k across 1,000 at 1km across etc etc (all figures fabricated, made them up to get the point across).

This is an area where more money should be spent. The success of DART gives me some hope that we're starting to take it more seriously though.

 

[12th Monkey]

We could do with a SpaceX rocket full of nuclear warheads and that might knock the thing off course.

The reason the missions to asteroids (Hayabusa, OSIRIS-Rex etc) are so important is that how we'd best alter their course depends upon how they are constituted. Some may be solid (particularly the metallic ones), but others are what are called 'rubble piles' - basically clumps of rock held together by gravity but filled with gaps.*

With a rubble pile, blowing it up might just turn one large object into many smaller ones on a similar course. DART shows one way (impacting the asteroid with a heavy weight), and that mission was astoundingly successful for a first try. Other ideas include painting one side so that solar radiation alters the course (sounds weird, but look up Yarkovsky and YORP effects), but that would be a mammoth task. We can also park something in orbit and use it as a gravitational tug. These last two options do depend upon having enough time though.


*How this is ascertained is so clever - NEAR Shoemaker went to Eros years ago, and orbited it whilst measuring he gravitational effects - far more complex than it would be with a sphere, because Eros is like an elongated potato. All of this is detected by doppler shift in the signal that NEAR sent back to Earth, which had to be corrected for the effect of the Earth's spin and orbital movements. I'm glad the people involved are much, much smarter than I am.

 

[Friesiansam]

On the other hand, the likelihood of a hugely destructive impact, during any of our lifetimes, is extremely small.

 

[podknocker]

On the other hand, the likelihood of a hugely destructive impact, during any of our lifetimes, is extremely small.

This is true, but it could happen within 6 months. If a rock changed its course, due to some gravitational anomaly, it could take 6 months possibly. We'd see something large and could prepare, but would it be enough time?

We get small lumps arrive every day, but they burn up and fall as dust. Anything bigger than 50m, would be catastrophic for a city, if it came in vertically and was travelling really quick.

It's a vast range of sizes and the damage can be slight, or severe. The thing is, if it's possible, then it can happen. Probability is on our side, but there could be a massive rock on its way now. If we spot it, we can monitor, but can we prevent impact?

 

[12th Monkey]

On the other hand, the likelihood of a hugely destructive impact, during any of our lifetimes, is extremely small.

And that is why I lose no sleep over it!

 

[12th Monkey]

gravitational anomaly

I'm not sure what you mean here. The effect of the planets on them is reasonably predictable in effect, unless they happen to get very, very close - and asteroids are too small and far apart to have a significant effect on each other.

 

[podknocker]

And that is why I lose no sleep over it!

It's the best way really. There are still enough threats around these days to worry about.

 

[12th Monkey]

It's the best way really. There are still enough threats around these days to worry about.

And we have media which work on the 'if it bleeds it leads' mentality. I did read a stat about the percentage of people who actively engage with the news and how this changed during the pandemic. Many switched off, and who can blame them?

 

[podknocker]

There are many 'wobbles' in the solar system, which cannot be predicted. The paths of planets and asteroids is governed by the mutual effects of gravity, between these objects. Prof Brian Cox explained this in one of his series.

For want of a better term, it's like the butterfly effect. A small change can lead to another one etc. Something a long way out can cause a change in something nearby. There are too many objects and variables out there to allow us to predict every possible outcome. Some call it chaos theory.

I like the film 'Gravity' where the random pattern of satellite destruction is created. So many bits of stuff flying around and you cannot determine where each fragment will go, to cause further damage. Once this starts, way out in the solar system, you cannot work out what will happen next.

In another example, imagine when a snooker player breaks the pack at the start of a frame. The slightest change in speed, angle, friction, humidity, static, chalk dust and condition of table cloth, all contribute the final position on the balls. I doubt there have been 2 identical breaks in the history of snooker. We'll never know, obviously.

 

[12th Monkey]

Again, it's not something I'd worry about too much - like I say, the effects of the planets are pretty predictable, and there are gaps in the asteroid belt where tugs from Jupiter etc have resonance and are therefore more likely to get shifted - the Kirkwood gaps. And like I say, the asteroids themselves are by and large too small and too far apart for there effects upon one another to be a significant worry.

The thing in Gravity is called the Kessler Syndrome, and that's a different thing - the gaps are not that big, and the orbital shell for geostationary is pretty narrow. Now that we should be concerned about! The asteroid belt is absolutely enormous and largely empty in comparison. Oh, and when collisions occur, their orbits tend to retain most of their angular momentum, so won't tend to dramatically change course.

I have a collection of meteorites though, so I'm really glad that bits do get to us - just the smaller ones, by and large...

 

[podknocker]

Kessler Syndrome and space debris is concerning. We've ruined the land and oceans, mainly with plastic and we've also ruined space, leaving all this junk flying around. I can't see an easy way of removing this stuff and we might need to live with this stuff forever.

Life is too short to worry about things you can't control anyway. If your number's up, then that's fate. There are many smaller threats to concern us, but again, they are mostly out of our control. The biggest threat to my life, is my age and I know I can't do anything about that!

 

[Friesiansam]

The amount of man made things things running around in low Earth orbit, are a far greater concern. Not because there is any great risk of a satellite hitting you on the head but, because of the increasing risk of collision in orbit, due to their sheer numbers.

Melon Husk and his monstrous ego, has made things much worse with more than 1000 broadband satellites. One collision would generate a vast number of fragments, with potential to cause a huge amount of destruction.

 

[podknocker]

The amount of man made things things running around in low Earth orbit, are a far greater concern. Not because there is any great risk of a satellite hitting you on the head but, because of the increasing risk of collision in orbit, due to their sheer numbers.

Melon Husk and his monstrous ego, has made things much worse with more than 1000 broadband satellites. One collision would generate a vast number of fragments, with potential to cause a huge amount of destruction.

It seems to be unavoidable in our modern world, although recreational space visits are going to make things much worse. We all need satellites, for all sorts of stuff, but I don't think there's a way of launching technology into space, without leaving all this launch shrapnel floating around. Even bits the size of a grain of sand are a problem, as some are racing round at 17000mph.

 

[12th Monkey]

The biggest threat to my life, is my age and I know I can't do anything about that!

I'm trying to postpone it, but in the long run...!

 

[podknocker]

I'm trying to postpone it, but in the long run...!

It's a great time to be alive these days, if you have access to the basic needs in life and even better, if you can spend your time chatting on a tech forum. As Roy Batty said in Bladerunner 'I want more life'. The thing is, if human lifespans could be extended by decades, this would have so many implications and the world could eventually turn into a Logan's Run scenario, where society is so enormous, there is a change and people are then allowed to live until 30 or 40 for example. I would like to be 18 again and know what I know now and live 200 years. I wouldn't want to be my age and live another 200 years, however. An artificially extended life is only enjoyable, if you have all the mental and physical faculties for the duration.

 

[abacus]

But could your brain adapt to a longer extended life. (Most oldies today don't understand youngsters today (And Vic versa) so how would you get on with an even more disconnect)

Bill

 

[podknocker]

But could your brain adapt to a longer extended life. (Most oldies today don't understand youngsters today (And Vic versa) so how would you get on with an even more disconnect)

Bill

Being 18 and not growing old, for 200 years would be great, but being old and staying old for 200 years, would be a living hell. A very long life would be ideal, if you had your youth and health for a long time.

I would imagine any new scientific breakthrough, would allow your brain to live longer, with all the other bits. The brain's capacity to learn and adapt and remember, might not be possible after 100 years, but some people are still compos mentis after a century, while the rest of their body has really suffered.

Extending lifespan, for more than a decade, or 2 isn't going to be possible, although some creatures don't age, or get cancer. Isolating the genes responsible for this is one thing, but using them to avoid, or delay human senescence is another matter. I think our mortality is something we can never overcome.

 

[Friesiansam]

Extending lifespan, for more than a decade, or 2 isn't going to be possible, although some creatures don't age, or get cancer. Isolating the genes responsible for this is one thing, but using them to avoid, or delay human senescence is another matter. I think our mortality is something we can never overcome.

If human lifespan did get greatly extended, it would be a disaster for this this planet. If we were living decades longer, the population would increase very substantially, very quickly, soon overwhelming Earth's resources and, all the other life we share this planet with. There are already far too many of us.

 

[jjbomber]

If human lifespan did get greatly extended, it would be a disaster for this this planet. If we were living decades longer, the population would increase very substantially, very quickly, soon overwhelming Earth's resources and, all the other life we share this planet with. There are already far too many of us.

The impending WW3 will sort it out!

 

[JDL]

I know why they did those alerts and it wasn't to warn anyone about anything. Ha.

 

[JDL]

If human lifespan did get greatly extended, it would be a disaster for this this planet. If we were living decades longer, the population would increase very substantially, very quickly, soon overwhelming Earth's resources and, all the other life we share this planet with. There are already far too many of us.

If human lifespan becomes greatly extendable, it won't be the likes of us who 'benefit' from such.