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60

Why were the SpaceX Crew-1 astronauts backed up by guards with automatic weapons? A NASA crew launch is a highly-visible symbol of US national pride. I mean, the slogan for the whole campaign is Launch America, and the message has always been "Launch American astronauts from American soil in an American capsule on American rockets (for the first time ...


43

Partial answer covering only Is this a new thing, or were similar military guards around to guard Shuttle crews as well? It is not a new thing. Photo by former colleague Michael Grabois at STS-101 crew walkout, 2000. The guards were not only on the ground. Image source Personal photo at STS-135 launch, 2011.


35

The apogee/ perigee of 2019-006A, the object likely shot down, was 260- 282 km, pretty low. Some of that debris could be quite a bit higher, but most of it will be lower, and all of it will have a new perigee/ apogee in that range, which will likely be shrinking quickly. It is expected that it will be similar to the debris cloud from USA-193 (Operation Burnt ...


18

Classified satellites are launched all the time. For example, fourteen KH-11 espionage satellites were launched between 1976 and 2013, and we still have no idea what they look like. So you can launch pretty much what you want and nobody will know for sure what it is. A satellite that does nothing would be suspicious, so you'd have to stick your warhead ...


15

At this time, it is not yet known. There are some 250 objects observed, but it takes time to catalog them all. The object destroyed was most likely MICROSAT-R (TLE catalog number 43947, which is in a 294 x 265 km orbit at 96 degrees inclination. Due to the nature of the event, it's likely some of the objects have apogees well above ISS orbit. At this ...


13

From Russian wiki on RS-82: RS-82 and RS-132 are unguided air-to-air, air-to-ground rockets developed during 1929-1937. Further developed into М-8, М-13 "Katyusha" rockets. It seems the final propellant was a solid fuel N developed by a group lead by A. Bakaev in mid 30s: nitrocellulose (collodion cotton) - 57% nitroglycerine - 28% dinitrotoluene - 11% ...


11

You're quite right that 150kg is unlikely to be the final maximum payload for Electron: SpaceX's Falcon 1 was almost immediately uprated with the addition of a Merlin-1C engine, and was nominally planned to be offered in an extended variant, Falcon 1e, that could take 1010kg to LEO. The most likely upgrade path probably consists uprating the Rutherford ...


9

The legal definition of "Weapon of Mass Destruction" in US law is quite broad (see https://www.schneier.com/blog/archives/2009/04/definition_of_w.html ), and an orbital kinetic weapon definitely qualifies if the projectile is big enough to re-enter in one piece. The FBI and/or ATF will want to have a talk with the owner.


7

Your question contains a couple of misconceptions: a kinetic kill vehicle must have the same kinetic energy as the satellite it intends to destroy No, it doesn't. It just needs enough kinetic energy to break critical parts inside the satellite. The same goes for micrometeoroids. If my understanding of orbital mechanics is correct, the speeds of the ...


6

The second image is ISRO's Polar Satellite Launch Vehicle which launched, among other payloads, Microsat-R (2019-006A) on Jan 24 2019, the probable target of the March 2019 ASAT test. The first image and related footage does, according to many official sources (eg. Air Force), show the ASAT missile.


6

According to the Defense Nuclear Agency report Operation Dominic I page 232 the destruct command was sent "to prevent any possible nuclear explosion." Nuclear weapon safety systems, while robust, are not invulnerable to damage when their carriers fail. The Range Safety procedures may have been informed by the accident just over a year earlier in Goldsboro, ...


5

The same ideas (and in some cases the same text) get repeated in a bunch of places (occasionally without modification) and without source which was not a compelling start. There were no references to actual arms, small or otherwise, in the readily available Volume I and II of the Project Horizon report. One commercial bookseller publishing a collection of ...


5

At what altitude range is the resulting debris field? Update: CNN: India anti-satellite missile test a 'terrible thing,' NASA chief says India's anti-satellite missile test created at least 400 pieces of orbital debris, the head of NASA says -- placing the International Space Station (ISS) and its astronauts at risk. NASA administrator Jim Bridenstine said ...


5

According to this source (in Russian), out of seven successful Salyut stations (amongst which were the three military Almaz stations) the modified NR-23 cannon was installed only on Salyut-3 (aka Almaz-2): The only prototype of such an installation was mounted at the Almaz-2 station, also known as Salyut-3. The above statement indirectly assumes that MIR ...


5

Salyut 3 is the only publicly acknowledged space to space weapon that has been orbited. It's possible that there are others which have been deployed in secret. The outer space treaty does not prohibit the deployment of conventional weapons in space, there doesn't seem to be any hurry to do it though, which is a good thing.


4

First of all, yes, a payload can be launched in to space that would remain at the key altitude for a HEMP, and stay there for some period of time. This has been discussed in terms of North Korea, for instance, which has launched satellites into an orbit that a HEMP attack would be possible, although they likely don't have the payload capacity to launch a ...


3

The U.S. detonated five nuclear bombs above the atmosphere. Not many minutes after one of these, nothing bigger than a molecule was left. So no debris, only a few radiation belts of high-energy electrons, which persisted for up to a few years. The other four explosions were likely similar. As for the Thor launch vehicle, it was just a single stage (not ...


3

The Chinese missile/glider was in LEO for some of its path, then re-entered the atmosphere as a glider. There is a good article in the Economist: https://www.economist.com/china/2021/10/23/chinas-test-of-a-hypersonic-missile-worries-america The speed while in the orbital phase of its flight would be similar to LEO satellites: about 7.8 Km/sec. Its altitude ...


3

Yes, ground based lasers have been used in an attempt to temporarily blind US satellites. Fortunately, it was the US that tried it. The US Army successfully tested the TRW-built Mid-Infrared Advanced Chemical Laser (MIRACL) at the White Sands Missile Range, New Mexico, on 17 October. During two firings, lasting about 1s and 10s respectively, the 2m- wide ...


3

Both things you mention have been worked on, conceptually or actually. The paper I'm familiar with on sling launchers is one by Geoffrey Landis, but he states he is expanding on earlier work. His paper is on ResearchGate - Journal of the British Interplanetary Society, Vol. 58, No. 9/10, pp. 294-297 (2005). Analysis of a Lunar Sling Launcher. That version is ...


3

I'll just follow up a bit on the collision. Per tweet and tweet and answer and answer and post: launch 5:40 UT (27 March 2019) MICROSAT-r 43947, 2019-006A over Abdul Kalam Island 5:42 UT I've put a recent TLE into Skyfield and we can see that the satellite was moving north from the equator towards Abdul Kalam Island, India. According to the image in India'...


3

Space to Space weapons seemed like a good idea, but really isn't that great for orbiting spacecraft. First of all, what is the use case? It would only really work for spacecraft in a similar orbit. Let's imagine that a spacecraft is coming towards you. Firing weapons to destroy the spacecraft might lead to an impact in the firing spacecraft, destroying it. ...


2

Not an actual bullet, but researchers fire plenty of things at spacecraft shields to test them. Here's one I found in full Performance of Whipple shields at impact velocities above 9 km/s. They fired aluminum balls in the range of .004g to .3g at 7 to 9.9km/s. The shield failed against .3g at 7km/s. That's 7,350J or about three times what a typical battle ...


2

Thanks to @Ohsin's comment I have plotted the propagated orbits of 57 tracked debris objects with published TLEs as well as the TLE for (whatever is left of) the original spacecraft and the original rocket body, as well as for the ISS. You can see that most of the debris still has a low periapsis where it was created, but a lot of it has aopapsis of 1000 to ...


2

Using a sling whirled around above the head, could someone on the moon throw a stone into orbit? tl;dr: probably deeply suborbital; 1192 meters, 38 seconds, either straight up or downrange at 45 degrees. And of course even if you had superhuman sling skills, your trajectory would either fly off into space (lunar C3 > 0) or return on an elliptical (C3 <...


2

Supplementary to @Jack's answer. Hat tip to @Ohsin for recommending this interesting video about the rocket, and the test itself: Last image seen by the kill vehicle, at ~10,400 m/s. The heat shield was ejected subsequently, and the IIR seeker locked on to the target at the expected range. The terminal guidance executed the ...


1

Looking at the question you are linking I would be inclined to say that it is possible assuming the astronaut's suit is flexible enough and the thrower has enough endurance. (Although, remember, the low periapsis. Combine that with the instability of lunar orbits and you can't say that it will stay in orbit!) I don't think spinning it above your head is ...


1

ICBM’s don’t typically fly at hypersonic speeds for the entire duration of their flight. They do typically cruise at altitudes above 100km to take advantage of reduced drag, but they do so without engines turned on. They follow suborbital trajectories with velocities that decrease up to apoapsis and increase upon reentry. This particular missile (avangard ...


1

It used to be called Operationally Responsive Access to Space. Fast means faster than now. The faster the better, it is not clear there is a lower limit, faster than launch on demand. But anything would be better than now, which is multiple months if not years out.


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