Posted on 09/16/2019 8:06:58 PM PDT by 2ndDivisionVet
Twice in the last month, the President of the United States has claimed that the Pentagon has weapons even more powerful than nuclear weapons, with the ability to easily kill millions. He is either bluffing, confused, or is incapable of understanding the difference between conventional and nuclear weapons.
President Donald Trump made the claim during remarks to commemorate the 18th anniversary of the September 11th attacks in New York, Washington, and Pennsylvania.
According to The Washington Post, Trump told an audience, emphasis mine:
The last four days, we have hit our enemy harder than they have ever been hit before, and that will continue, Trump said, apparently referring to the Afghanistan war and drawing applause from the crowd. And if for any reason they come back to our country, we will go wherever they are and use power the likes of which the United States has never used before and Im not even talking about nuclear power. They will never have seen anything like what will happen to them.
(Excerpt) Read more at foxtrotalpha.jalopnik.com ...
I wonder how much punch a 500 or 1,000 pound rod might have, compared to a conventional bomb, if it could get to mach six or ten? Or even 16,000 mph, like the HTV-2 test vehicle did a decade ago?
Even a 100 pound sabot at those speeds might pack a lot of energy and penetration ability.
They might even fill it with depleted uranium, to increase its mass to cross section ratio, as folks have done for decades with hypersonic anti-tank kinetic energy penetrators.
The drag acceleration overcomes the gravitational acceleration as you get deeper into the atmosphere, slowing the object down. The amount it slows is dependent on the drag coefficient, a function of mass and the area and ‘shape’ as seen by the ‘wind stream’.
You are thinking through the problem correctly. Now you have to apply the right numbers. But the bottom line is no rods from god.
I poked at wiki and google on the subject because I don’t understand where people get the notion that it works given the physics. The wiki description talked about starting from orbit at Mach 10, noted that drags slows that down “considerably”, then proceeds to talk about impact energy as if its still traveling at Mach 10. That’s really misleading the general public.
“The wiki description talked about starting from orbit at Mach 10, noted that drags slows that down considerably”
Additional onboard thrust (engine) could also enhance impact speed.
I’ll give you a good analogy to go along with the question/problem. This is actually from personal experience in a way.
I have been a skydiver since the very early 80’s (not so regular any more, but still many thousands of jumps over those years). I was trained in the military and some of those jumps were high altitude jumps from as high as 35,000 ft.
A skydiver face to earth in freefall at 30,000 has a terminal velocity of about 250 mph, depending on size, weight, and how he ‘shapes’ his body in freefall. At 10,000 ft, that same skydiver with same shape, size and weight has a terminal velocity of about 150 mph, and by 2500 ft has a terminal velocity of about 120 mph. (I never clocked myself lower than than, sorry ;) ).
If I was Richard Branson or the red bull guy and I started at 100,000 ft, at 80,000 ft I would be doing about 500 mph but by the time I got to 2500’ I would still be down to 120 mph.
Now a refrigerator in the same scenario might have a terminal velocity at impact of 200 mph, and you might even get a telephone pole up to 400 mph, but that’s nowhere near Mach 10.
Hope this helps.
A single Trump tweet can cross all seven continents within 900 milliseconds inflicting stunned bewilderment and confusion upon hundreds-of-millions.
Reloading.
Yes but that is not the rods from god concept, which says you can take a fairly simple tungsten rod with a guidance system and let gravity do the work.
Now its a spaced base missile, Much more expensive, just as predictable and detectable from a defensive stance (you can see where it is and know when you are vulnerable from the orbit physics), still susceptible to being shot down, disabled, or just plain aging out (cheap satellite systems don’t live long in the space environment, and the expensive ones have failures as well. Basically space is still hard.)
This is why there is so much focus on hypersonics. You keep the system on the ground where it can be maintained until needed, and you are anywhere on the planet in 20 minutes (or so they say, as I don’t really work on hypersonics).
“A single Trump tweet can cross all seven continents within 900 milliseconds inflicting stunned bewilderment and confusion upon hundreds-of-millions.”
True. Ain’t it great?
BTW - I love your wall threads. Keep’em comin’.
Imagine a rod falling that creates a vacuum in front of it, giving it no air resistance whatsoever...kind of like a cavitating torpedo.
But what do I know...I run a t-shirt company.
In New Mexico...
Got any good MAGA t-shirts? ;)
If we ever have a full-scale unlimited war again, it will be our last war and the end of civilization on this planet.
From Geosynchronous orbit, an object would accelerate for 22,000 miles, and decelerate for about 15 when the air thickened. If it was initially fired from a rail gun, or travelling rapidly relative to the surface of the Earth in a high but not geosynchronous orbit, that could give it a few thousand miles per hour head start as well.
Apparently some meteorites that get through the atmosphere, can impact the surface at over 40,000 mph, like the estimation of the one that hit Gosses Bluff, Northern Territory, Australia:
“I love your wall threads”
Thanks - I love a good project.
Some points, and possibly an orbit mechanics primer:
1) If you assume its an orbiting system, you start with the velocity required to maintain orbit, with that velocity being parallel to the ground, not perpendicular. In LEO, that’s about 7 km/sec. In GEO its about 3 km/sec. Its very expensive propellant wise to change orbits in any large way. That’s why it takes BIG rockets to get into orbit in the first place. Once you are there, you are pretty much there because you couldn’t bring another BIG rocket of fuel with you. But you can make some orbit changes easier than others...
2) So to lower an orbit you thrust opposite direction of flight. This changes the orbit but you still have an orbit, only now the farside of the orbit will be lower (perigee) and if you go full orbit you will wind up back where you are now (apogee). If you get perigee low enough (~100 miles altitude from earth surface) you will get enough drag that the drag itself becomes a ‘thrust’ in the direction opposite flight and the orbit gets lowered more. Do this enough and you re-enter the atmosphere.
So your scenario is not the way things would or could physically happen given the limits of what we can put into orbit in the first place, and what we can afford.
3) Meteorites sometimes can become a whole new ball game. Fortunately most things in our solar system orbit the sun in the same general direction, and most meteorites will enter our atmosphere more are less travelling with the earth as it orbits the sun. The atmosphere slows or oblates them and most never even get to the ground. Now if that meteorite is coming from a direction opposite the Earths orbit (very rare apparently) then you have the Earth traveling about 27000 mph one way and a meteor going the other way, and if its big enough, yes, you get a big crater.
Achieving this type of destruction by a manmade rods from god system would be so expensive you might as well just nuke em’.
“When US ground forces show up, they are ready and eager to fight.”
True... as long as we keep the damn lawyers and politicians from writing the ROE’s. God bless those youngsters.
Chemical and Biological weapons ARE vastly more powerful than nuclear weapons. If a nuke lands nearby you could survive. With either of the others you are dead, no matter what gear you have.
I wouldn’t put much stock in directed energy weapons, or plasma rays - none of those things are worse than nukes and nothing beats a DNA targeted Ebola-like plague ...
I know about them, why doesn't this author?
...and many of them agree with me
Thanks for the interesting discussion.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.