Asteroid defense ideas

[Moontanman]

14 minutes ago, Mordred said:

That's a good plan however likely never happen outside of previous tests done thanks to banning nuclear tests. So we're likely going to need to rely on previous tests and using mathematics from  there

What's unusual you do know EMP involves Gamma rays hence photons.

You get reduction of strength due to the sperically symmetric distribution described by 1/r^2. That's an idealized scenario that assumes zero directivity.

It's a miniscule distance from the moon to Earth for photons.

Again you sad the effect would not be significant not me. That is why what you asserted was deceptive, you tried to convince us the EMP from the moons orbit would be dangerous to the earth in some significant way, then when called out on it you admitted the effect would be minimal and not dangerous. That is deception. 

I have no doubt that such an important experiment could be approved if proposed by the proper authorities. 

Edited May 26 by Moontanman

[Sensei]

The simplest defense would be to harvest/mine a potentially dangerous solar system asteroid long before it is on a straight path to Earth, using transport rockets that take off in such a way that they are slightly displaced to another orbit, just because rocket(s) started from it. Most sensible for some metallic/solid asteroids.

Mining on the asteroid would also allow nuclear weapons (useless here on Earth) to be placed there, in the core, just in case they are urgently needed before the asteroid is fully depleted but on its way to Earth. The best time to blow up such an asteroid is when it is on the other side of the sun from Earth, 300 million kilometers away. Before blowing it up, matter could be extracted from it in this way:

Of course, to begin with, what is needed is proper detection of all objects orbiting the Sun at a distance of about 200 million km. What is needed, then, is a cloud of drones/satellites to do this.. Then extend distance in the future to further areas of solar system. Not exclusively in accretion disk orbit, but also sphere around the Sun, to detect also non-solar objects..

 

[Mordred]

31 minutes ago, Moontanman said:

Again you sad the effect would not be significant not me. That is why what you asserted was deceptive, you tried to convince us the EMP from the moons orbit would be dangerous to the earth in some significant way, then when called out on it you admitted the effect would be minimal and not dangerous. That is deception. 

I have no doubt that such an important experiment could be approved if proposed by the proper authorities. 

That's correct at the moons orbit even using the 100 megaton value 700 joules/sec isn't a huge risk. That's why I stated you need to react at that distance minimal. 

Anyways let's simply chock thus up as miscommunication and move on. We all agree nukes could be used provided it's far enough away. As well as there being no chance of the debris to enter Earths atmosphere 

Edited May 26 by Mordred

[Moontanman]

2 minutes ago, Mordred said:

That's correct at the moons orbit even using the 100 megaton value 700 joules/sec isn't a huge risk. That's why I stated you need to react at that distance minimal. 

Damn, like trying to nail jello to a tree, your post hoc ability to explain this away is amazing. Why can't you just admit you were wrong? Mordred, you are far better educated than me and I like that you are here to explain these things, you've set me straight several times but in this case IMHO your own exaggerated fear of nukes has clouded your judgement. 

There was no need to do this, there was no need to assert the EMP effect, your own link to star fish prime clearly stated the EMP effect was most effective at around 300 miles and your own calculations showed the effect of even the outrageous sized 100 megaton imaginary bomb would not be a danger yet you asserted it was.  

Why? Why not use a realistic sized bomb and show how close it would have to be to pose a realistic danger?  

I am not your equal in any way but I can recognize emotional deception when I see it, at every turn you rejected any information that indicated that nukes aren't the extreme danger you want others to think they are.

I readily admit that current culture seems to be promoting this idea of a nuke being all powerful and all dangerous through fear mongering what some terrorist or rouge nation might do with one bomb but these emotional notions should not enter into a scientific discussion. 

To have a productive discussion requires the are all on the same page not out chasing deceptive or emotional arguments, when I am wrong I readily admit it...

[Mordred]

Why wouldnt

11 minutes ago, Moontanman said:

 

There was no need to do this, there was no need to assert the EMP effect, your own link to star fish prime clearly stated the EMP effect was most effective at around 300 miles and your own calculations showed the effect of even the outrageous sized 100 megaton imaginary bomb would not be a danger yet you asserted it was.  

 

Where oh where did I claim that? I described the Starfish distance of 250 miles. I also provided a link (wiki) with values related to that test as well. That link highlighted some of the resulting damage to which you asked how many deaths resulted from it  

I made no claim regarding 300 miles.  I did an examination using a 100 megaton range at the lunar distance.

 

Edited May 26 by Mordred

[Moontanman]

5 minutes ago, Mordred said:

Why wouldnt

Where oh where did I claim that? I described the Starfish distance of 250 miles. I also provided a link (wiki) with values related to that test as well

I made no claim regarding 300 miles.  I did an examination using a 100 megaton range at the lunar distance.

 

Your link said that around 300 miles was the most effective height and your examination for a 100 megaton blast was deceptively used to assert the danger of such a EMP from the distance of the moon.

You be you dude, I see no reason to try and reason this any further. 

[swansont]

32 minutes ago, Sensei said:

Mining on the asteroid would also allow nuclear weapons (useless here on Earth) to be placed there, in the core, just in case they are urgently needed before the asteroid is fully depleted but on its way to Earth.

How would you do this? On an asteroid that’s a few hundred meters across?

32 minutes ago, Sensei said:

The best time to blow up such an asteroid is when it is on the other side of the sun from Earth, 300 million kilometers away. Before blowing it up, matter could be extracted from it in this way:

Of course, to begin with, what is needed is proper detection of all objects orbiting the Sun at a distance of about 200 million km.

What if it’s not orbiting the sun?

32 minutes ago, Sensei said:

What is needed, then, is a cloud of drones/satellites to do this.. Then extend distance in the future to further areas of solar system.

Why do you need a “cloud” of drones/satellites? Wouldn’t a few dedicated telescopes suffice?

 

[Mordred]

11 minutes ago, Moontanman said:

Your link said that around 300 miles was the most effective height and your examination for a 100 megaton blast was deceptively used to assert the danger of such a EMP from the distance of the moon.

You be you dude, I see no reason to try and reason this any further. 

Where in that link describes what you just described ?

Are you positive there isn't some miscommunication here ?

 

Let me ask you a question A nuke exploding at the surface and a nuke of the same magnitude exploding at a higher elevation.

Which EMP pulse is more dangerous ? The one on the surface or the one at an elevation?

Edited May 26 by Mordred

[Sensei]

Just now, swansont said:

What if it’s not orbiting the sun?

How many times has a Powerball winner won twice or three or four in a row?

You accept the risk every time you leave your apartment. You are more likely to die in a car accident than in any space accident. And you adjust to the most likely possibilities. And you solve them.

Man has detected/confirmed one, so far, AFAIK.

 

IOW, rephrasing the question, what if the ejected black hole is on its way toward Earth? You can learn about it with a similar delay as in the case of an ordinary space asteroid, or less. i.e. do you already have a plan against "ejected black holes"?

https://science.nasa.gov/missions/hubble/hubble-sees-possible-runaway-black-hole-creating-a-trail-of-stars/

 

Just now, swansont said:

Why do you need a “cloud” of drones/satellites? Wouldn’t a few dedicated telescopes suffice?

Haven't currently existing telescopes shown their uselessness by failing to detect asteroids flying toward Earth?

How many do you need to use cloud in the name? Is 10 a cloud? Is 20 a cloud?

 

 

 

[Mordred]

3 hours ago, TheVat said:

 

Nota bene:

Only eleven percent of the US arsenal are warheads of yield greater than a megaton - those are the B83s, at 1.2 MT each.   The Russians largest are 800 KT.  Just pointing this out, in response to the talk of 50 MT warheads - such do not exist.  

 

You might want to consider 

https://en.m.wikipedia.org/wiki/Tsar_Bomba

The yield of tsar Bomba.

[Moontanman]

4 minutes ago, Mordred said:

You might want to consider 

https://en.m.wikipedia.org/wiki/Tsar_Bomba

The yield of tsar Bomba.

The Tzar Bomba no longer exists, it was a one off 50 megaton bomb so large only one could barely be carried to the text site by the largest bomber they had, what is your point?

Edited May 26 by Moontanman

[Mordred]

I realize it no longer exists but it does point out we can produce something of that magnitude.

 I'm more interested in seeing if there is any good studies of that test accessible. May give some better numbers to work with.

Edited May 26 by Mordred

[Moontanman]

2 minutes ago, Mordred said:

I realuze it no longer exists but it does point out we can produce something of that magnitude.

 I would imagine that by now we could make them even more powerful and maybe physically smaller but no one has them now mostly due to many small bombs being more effective than one big bomb in destroying a ground target. 

[Mordred]

Well as I described earlier there's nothing stopping us from loading a craft full of warheads so we really aren't limited in megatonnage.

 

[swansont]

46 minutes ago, Sensei said:

How many times has a Powerball winner won twice or three or four in a row?

You accept the risk every time you leave your apartment. You are more likely to die in a car accident than in any space accident. And you adjust to the most likely possibilities. And you solve them.

Man has detected/confirmed one, so far, AFAIK.

And yet you brought it up in your post.

“Then extend distance in the future to further areas of solar system. Not exclusively in accretion disk orbit, but also sphere around the Sun, to detect also non-solar objects..”

So I’m asking how we destroy the asteroid that your proposed system was set up to detect.

46 minutes ago, Sensei said:

Haven't currently existing telescopes shown their uselessness by failing to detect asteroids flying toward Earth?

They’ve detected asteroids, so they aren’t useless. They might not be 100% efficient, but you’ve not identified the flaws, or how how your proposal fixes anything.

46 minutes ago, Sensei said:

How many do you need to use cloud in the name? Is 10 a cloud? Is 20 a cloud?

It’s your terminology. You’re supposed to tell us what you mean.

[Sensei]

49 minutes ago, swansont said:

And yet you brought it up in your post.

“Then extend distance in the future to further areas of solar system. Not exclusively in accretion disk orbit, but also sphere around the Sun, to detect also non-solar objects..”

So I’m asking how we destroy the asteroid that your proposed system was set up to detect.

From nothing, you can only grow, gaining experience as you go.. without detection the rest is irrelevant..

49 minutes ago, swansont said:

They’ve detected asteroids, so they aren’t useless. They might not be 100% efficient, but you’ve not identified the flaws, or how how your proposal fixes anything.

They are useless if they warn days or weeks before a close flyby of an asteroid hundreds of meters in size.

IOW, disallowing for any sensible reaction (which requires years of preparation, or in extremity months)

49 minutes ago, swansont said:

It’s your terminology. You’re supposed to tell us what you mean.

Now you start with nothing. Then you build one, launch, place in orbit, then you build a second, launch, place in orbit, then you build a third, place in orbit.. then you repeat it over and over and over..

Endless work. Some will have problems sooner or later and need to be replaced.

 

"Cloud" is "a dynamically allocated number of resources to meet current demand."

 

[swansont]

44 minutes ago, Sensei said:

They are useless if they warn days or weeks before a close flyby of an asteroid hundreds of meters in size.

And why did this happen? What about the NEO Surveyor mission, already in the works? Is there some deficiency in that?

Do you have any facts or science to present, or is it just going to be a bunch of hand-waving?

[TheVat]

3 hours ago, Mordred said:

You might want to consider 

https://en.m.wikipedia.org/wiki/Tsar_Bomba

The yield of tsar Bomba.

My NB was in regard to the current arsenals, which were suggested as providing the charges for these hypothetical asteroid deflectors.  Am aware of the bad old days of multi-MT blasts.  A close relative lived most of his life a couple miles from the nation's foremost nuclear bomber base, and I used to live uncomfortably close to StratCom hq, so have been fairly aware of the arms race history and living in the crosshairs.  

The main problem with Castle Bravo or Tsar Bomba sized bombs, as  mentioned in a following post, is difficulty in delivery of such  massive weapons to a target.  

My reading of this discussion so far is that a smaller charge is easier to deliver to an asteroid, provided you have enough lead time to strike it at a great distance and thus gain the required deflection with less force.  

 

[Mordred]

No problem quite frankly delivery is a large part of the problem to begin with. We haven't particularly established how much can or can't be reasonably delivered. Obviously we're not firing missiles from Earth to the asteroid so you would need a craft. That craft will determine how big a payload it can deliver. 

[swansont]

 

4 minutes ago, Mordred said:

No problem quite frankly delivery is a large part of the problem to begin with. We haven't particularly established how much can or can't be reasonably delivered. Obviously we're not firing missiles from Earth to the asteroid so you would need a craft. That craft will determine how big a payload it can deliver. 

There’s a treaty preventing nuclear weapons in space (the Outer Space Treaty), which would obviously be suspended in this scenario, but you probably aren’t going to be parking nukes in space in anticipation of hitting an asteroid that hasn’t already been identified as a very likely threat.

Multiple parts of the plan would have to be in place beforehand.

[Mordred]

Precisely when you get right down to it every solution has infrastructure hurdles. I would think it would be far easier to get a gravity tractor solution than it would be convincing every involved government nukes are needed.

[zapatos]

6 hours ago, Airbrush said:

There are 3 things necessary to intercept an asteroid:   find them early, find them early, and find them early.  We don't know when, so we need to think of a method than can be put into action sooner than gravity tractors can.

How far away CAN we send nukes to intercept?  As far as you can send them.  So again, you need to find them early so you have time.

Also work on gravity tractors, in case we have hundreds of years to prepare, but they will take a lot longer to be ready for action, and we may not have that much time.  If you break it apart far away, the pieces will fly apart, but I am wondering if a nuclear blast, at the correct distance, would melt and fuse loose material together, and it would not break apart a rubble pile.

So now you are saying we DO have the time?

4 hours ago, Moontanman said:

 I would imagine that by now we could make them even more powerful and maybe physically smaller but no one has them now mostly due to many small bombs being more effective than one big bomb in destroying a ground target. 

Aren't many small bombs the same as one large bomb? We can use 100 small or one large. Basically the same thing I believe.

[Ken Fabian]

I'm with Airbrush on this and think nuclear devices delivered by variants of existing rockets would be the preferred means, probably the only one possible any time soon. Longer term - and I do think meteor defense is best viewed as  long term - other options may become possible.

 

18 hours ago, Mordred said:

You need a spacecraft to deliver the nukes. So where is the difference between that and a gravity tractor ?

Delivered and it is done versus delivered and just getting started. Much more deflection from less payload. Shorter mission times. Uses familiar technologies with lots of existing knowhow and capability. The links people have provided, including yours appear to support that although different asteroid examples and different units make direct comparisons a bit tricky - at least for me.

https://arxiv.org/pdf/physics/0608157 with Apophis (320m diameter, 46 million metric tons) as example for a 1 ton gravity tractor -

Quote

The acceleration of the asteroid in this
configuration is then 3.7 x 10-5
meters/sec/year

3.7mm per sec per year (? Someone else should check units and arithmetic?)

https://ntrs.nasa.gov/api/citations/20205008370/downloads/Nuclear_Devices_for_Planetary_Defense_ASCEND_2020_FINAL_2020-10-02.pdf with 560m diameter object and 550kg payload -

Quote

a 1 Mt NED with a mass of approximately 550 kg is capable of imparting a change in velocity of approximately 6.5 to 16.5 cm/s to a ~560 m diameter NEO, depending on the NEO’s composition [4]. This is significant because NEO deflection usually requires only one to several cm/s of velocity change, depending on circumstances including warning time, and 550 kg is not a difficult payload mass to deliver to an NEO. By comparison, imparting a velocity change of ~6.7 cm/s to a similar model asteroid using KIs requires a total KI spacecraft mass of 605,900 kg [11], which would certainly be impractical. Finally, it should be noted that the 1 Mt NED results described here are merely for example purposes and 1 Mt is more than would be needed for the most probable future NEO threats.

65 to 165mm per sec in a few seconds to minutes with a single 1 megaton nuclear device for a significantly larger object. Having the device stationary with respect to the asteroid seems to be preferred over one coming at it at high velocity but not sure how that would work directly along the trajectory.They look to smaller than 1 Mt explosions as preferred - several small ones better than one bigger one.

Spinning object? Having a quick search for rotation rates - it sounds like a large rubble pile would max out at 1/4 rotation per hour, slow enough for a nuclear detonation to give directional push. Small ones would be suitable for dispersing blasts.

Too close to Earth? The "nuclear devices" paper deems several months of warning as a short warning, late response scenario and doing the detonations more than a month out from expected impact is considered a rapid response. I can't see that as an EMP risk to Earth that far out. Anything as close as the moon will be days at most away - too late, kiss arses bye bye.

Nukes not designed for use in space? I expect some probably are even if that isn't advertised; the potential for nuclear warfare to happen in space has been known a long time; it may be against arms agreements to put any into space but military planners always look beyond existing treaties if only on an Irish basis - to be sure, to be sure.

 

[Mordred]

That's fair nukes are one option. The detail many are missing though is that we're also not restricted to a single 1 ton craft for the towing. The first link you supplied gets deflection in 20 days in the examination  it did there. I already posted near the beginning of this thread another paper that uses several gravity tractors to greatly speed up the time.

Here is a related statement in the paper relating to nukes vs tractor.

"operation as well. Finally it is very critical that neither NASA nor any other agency involved in addressing this challenge underestimate the degree to which the international community, both at the state level and that of the general public, will demand to be involved in and ultimately be satisfied with many of the decisions regarding NEO deflection.  Fragmentation of the NEO, uncertainty in the execution and the results, and even nuclear explosions and radiation will be of enormous concern to the world public.  Where more certain and benign methods are available to accomplish the deflection such instantaneous but risky approaches will not be acceptable. The Gravity Tractor, where capable of meeting the deflection challenge, is both technologically and societally the most preferable deflection option.".

 

I tend to agree with that quoted section. Particularly since a 1 ton craft is trivial compared to the rocket fuel consumption to reach escape velocity.

As we all seem to agree on using Apophis then according to this link we simply need to miss an 800 km gravitational keyhole.

https://en.m.wikipedia.org/wiki/99942_Apophis

As your first link examines this 20 days that it gives is quite reasonable.

Edited May 27 by Mordred

[zapatos]

Just something I found on Wikipedia...

Quote

Present capability

As of late 2022, the most likely and most effective method for asteroid deflection does not involve nuclear technology. Instead, it involves a kinetic impactor designed to redirect the asteroid, which showed promise in the NASA DART Mission. ^[107] For nuclear technology, simulations have been run analyzing the possibility of using neutron energy put off by a nuclear device to redirect an asteroid. These simulations showed promise, with one study finding that increasing the neutron energy output had a notable effect on the angle of the asteroid's travel. ^[93] However, there has not been a practical test studying the possibility as of April 2023.

https://en.wikipedia.org/wiki/Asteroid_impact_avoidance#:~:text=An object with a high,a spacecraft with the asteroid.