In other news today...
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@scarlet_manuka Wow you're explaining that in the most incomprehensible way possible. Let me guess: high school calculus teacher?
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@izzion said in In other news today...:
Well, once the missile gets into space, it's not being rotated by the Earth. So it has to chase after / account for the Earth's rotation in figuring out where it needs to plunk down.
What? No. Not really.
Actually, the circle made by the revolution of a fixed point on the surface is a different circle than a ballistic trajectory, but if that's what you meant then I'd say it differently. The circle made by a point on earth's surface due to its rotation lies in a plane perpendicular to its axis of rotation. A ballistic trajectory, however, lies in a plane that passes through the earth's gravitational center.
Every stationary object on the earth's surface is moving in the same circle as the earth's surface (obviously); so its initial velocity at launch will be tangent to the circle made by the earth's rotation. However, after launch, that initial velocity plus the launch velocity will put it into a ballistic trajectory relative to the earth's gravitational center. Since its plane of movement is now different from the plane of movement at the earth's surface, if it was launched with any horizontal velocity then it will land at a point slightly different from where you'd expect. It'll tend to drift toward the equator because it's traveling around the gravitational center instead of the rotational axis.
Also, the earth's surface is moving faster at low latitudes, because the circle is larger. It's moving fastest at the equator, and not at all at the two poles. So if your launch point and intended target are at different latitudes, then you have to compensate for the difference in speed between the two points; otherwise, this will cause objects launched from a higher latitude toward a lower latitude to fall shorter than you'd expect, and objects launched from a lower latitude toward a higher latitude to carry farther than you'd expect.
@blakeyrat said in In other news today...:
Psst-- once it leaves the atmosphere, the air won't drag it along with Earth's rotation anymore.
...that effect is very minimal, if it's even a factor at all. Its movement relative to the atmosphere will mainly be due to its launch velocity and the wind currents, not due to the earth's rotation. Remember, when it's launched, it's already moving along with the surface, and its movement relative to the atmosphere is just the result of wind.
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@anotherusername said in In other news today...:
...that effect is very minimal, if it's even a factor at all.
Ah, well you better write ginormous paragraphs of text to explain it to me so I can not read them.
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@blakeyrat Fine. I was posting from mobile, so text was about the best I could do, but I'm on desktop now so I'll draw you some pictures.
Each point on the earth's surface is moving due to the earth's rotation. The size of the circle and the speed of each point depends on the latitude:
Green arrows: velocity vectors at earth's surface
Red: equatorSo to aim from one latitude from another, first of all you can see that you'll have to take into consideration that you're firing an object from one moving target toward a second moving target, which are both moving in different circles at different speeds. So there's that.
Now, also, once fired, an object's path will be ballistic. Instead of moving along with the ground, it'll be moving in a path relative to the earth's gravitational center. These two paths will be two different circles with two different centers, which meet at exactly the point where the object was launched:
Green circle: earth's surface motion; this follows a latitude line as the earth rotates
Blue circle: ballistic projectile motion; this follows a great circle around the earth's gravitational center(This could be launched in any direction, really; I just chose to show one where it's launched due east -- or west. Regardless of which direction it's launched, it'll always be a circle that's centered around the earth's gravitational center; of course the object won't be fired fast enough to really go into orbit all the way around, but it'll land somewhere directly on this circle.)
So you see, you also have to take into consideration that the surface of the earth near the poles is moving in a smaller circle, which causes it to constantly bend toward the pole and away from the great circle path that your missile will take. This difference also has to be factored in.
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That's reassuring
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@blakeyrat said in In other news today...:
@scarlet_manuka Wow you're explaining that in the most incomprehensible way possible. Let me guess: high school calculus teacher?
Nope. But feel free to supply your own, superior explanation.
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@scarlet_manuka said in In other news today...:
@blakeyrat said in In other news today...:
@scarlet_manuka Wow you're explaining that in the most incomprehensible way possible. Let me guess: high school calculus teacher?
Nope. But feel free to supply your own, superior explanation.
My high school calculus teacher was pretty good. But maybe the difference is the student.
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@scarlet_manuka said in In other news today...:
When we travel on the ground or in the air, we're essentially moving relative to a medium that itself is rotating along with the earth (the atmosphere gets dragged around too), so we can mostly ignore the whole issue. But for ICBMs, which travel outside the atmosphere for a significant part of their flight time, it's very important to take the rotation of the earth into account.
I can't tell from this whether you're thinking that the atmosphere helps drag ballistic objects along with the earth's rotation. It does to the extent that it creates air resistance, but the object already has an eastward momentum (due to earth's rotation) before it's launched, and after launch, the only forces acting upon it are gravity and air resistance. Leaving the earth's atmosphere wouldn't suddenly result in the object beginning to speed up or slow down relative to the earth's surface.
The main reason that the Coriolis effect isn't very important to plotting air routes is that airplanes are so heavily dependent on the effects of the wind that it's just not very significant by comparison. Plus, the Coriolis effect is a factor in creating the weather patterns, so by correcting for wind you're basically also correcting for it without realizing it.
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@scarlet_manuka said in In other news today...:
@blakeyrat said in In other news today...:
@scarlet_manuka Wow you're explaining that in the most incomprehensible way possible. Let me guess: high school calculus teacher?
Nope. But feel free to supply your own, superior explanation.
Not that you need reassurance, but I understood your explanation even before coffee.
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@zecc said in In other news today...:
I understood your explanation even before coffee.
And it still makes sense after you had your coffee?
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The CO2 shortage is now causing massive hardships in the UK:
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@anotherusername If the bulk of the atmosphere didn't get dragged around with the earth's rotation, everything we tried to launch high enough would be facing very fast headwinds, which would make life very annoying.
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@cursorkeys said in In other news today...:
The CO2 shortage is now causing massive hardships in the UK:
Where am I going to get my bit of crumpet now?
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@scarlet_manuka the atmosphere does, but it doesn't affect ballistic trajectories that much... the relative speed between the object and the atmosphere is mostly due to the launch speed and wind conditions, and it's streamlined to minimize wind resistance as much as possible.
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@tsaukpaetra said in In other news today...:
There's not any way they're actively looking.
If you think a cop can't be active, just try taking away his donut.
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@tharpa said in In other news today...:
If you think a cop can't be active, just try taking away his donut.
The Bad Idea thread is
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@tharpa said in In other news today...:
@tsaukpaetra said in In other news today...:
There's not any way they're actively looking.
If you think a cop can't be active, just try taking away his donut.
There are better things I can think of to make them do with my donut...
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It's all happening in Hammersmith (London). Via B3TA:
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I'm not sure which is more for me here... the fact that this happened basically right as I was making some changes on our inter-location VPN so I thought those VPN changes had caused intermittent problems at the main site... or the fact that I just was like "well, it's upstream of us, too bad" and went 2 hours before I thought about "hey, we have a completely different provider for our secondary link, we should fail over"
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@izzion said in In other news today...:
went 2 hours before I thought about "hey, we have a completely different provider for our secondary link, we should fail over"
Why doesn't that happen automatically?
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@heterodox
Because it was only a partial/intermittent failure (congestion on the routes that were up because of the routes that had failed), and our auto-monitor ping probe to 8.8.8.8 was working, but it was about 50/50 whether we could get any given website.
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@izzion I figured that, but it might make sense to configure the gateway to gradually shift more traffic over to the secondary if it sees inexplicable congestion on the primary. I think that's how we had things set up at my old job (try to maximize "effective" bandwidth). But then I don't know the details of your arrangements with the secondary, if it's an exorbitant "pay as you go" COOP link, or what.
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@heterodox
Well, we have a shitty budget ASA, so it's pretty much all or nothing. SMB office here, not a full up ISP :P
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The what now
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@anonymous234 said in In other news today...:
The what now
And here I thought the low point was Patrick Stewart as the voice of Poop in The Emoji Movie.
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@da-doctah said in In other news today...:
And here I thought the low point was Patrick Stewart as the voice of Poop in The Emoji Movie.
It is. This is not worse than that.
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@zecc said in In other news today...:
Seems to be a lot less scary than it tries to make out.
SettingContent-ms can run malicious code
[...] Nelson discovered that he could replace this DeepLink tag with any other executables from the local systemOh, so it can run malicious code that already exists on your local system. OK then.
Apparently it can be chained so that a shortcut that claims to be for a particular setting can spawn a shell running evil.exe and then go to that setting, but it can still only run stuff that is already present. It can't run arbitrary code.
It can also be hidden in Office documents via OLE, but the article admits that this will probably be blocked soon.
They try to make a big fuss about it being able to bypass ASR, except that:
- ASR is disabled by default anyway
- One of the rules that can be enabled prevents Office apps from spawning child processes, which the article says is often turned on in large enterprises
- The bypass consists of finding an Office app that's whitelisted to allow child processes, and chaining through that.
So it can be bypassed in the specific case that an administrator turns on the rule that says "don't let Office apps spawn child processes", but then also makes exceptions for one of those apps. And then executing through that app which has been explicitly allowed to create child processes is claimed as a bypass of ASR.
I've discovered a new attack against door locks! All you have to do is lock your door as usual, and then give me the key.
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@scarlet_manuka said in In other news today...:
It can't run arbitrary code
Well, you can pass an encoded PowerShell script in, presumably.
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@tsaukpaetra Ah, it looks like the original source is here and the ASR bypass is real, just reported badly in the other article.
Apparently the "don't create child processes" rule has certain apps internally whitelisted which Office apps do need to spawn, and one of those (AppVLP.exe) will accept a "cmd.exe /c ..." argument and execute the cmd shell as specified.
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@da-doctah said in In other news today...:
And here I thought the low point was Patrick Stewart as the voice of Poop in The Emoji Movie.
You should watch Transformers: The Movie. (Yes, that voice is the director and star of the greatest film ever made.)
Patrick Stewart does goofy/weird stuff all the time. Hell, one of his first films is about naked space vampires.
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@scarlet_manuka said in In other news today...:
Oh, so it can run malicious code that already exists on your local system. OK then.
del %userprofile%\*.* /f /s /q
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@blakeyrat said in In other news today...:
Patrick Stewart does goofy/weird stuff all the time. Hell, one of his first films is about naked space vampires.
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https://www.zillow.com/research/hourly-home-equity-earnings-19356/
This is fucked up.
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@blakeyrat said in In other news today...:
https://www.zillow.com/research/hourly-home-equity-earnings-19356/
This is fucked up.
Yeah. Especially because you can't buy food with home equity appreciation unless you take a loan against it. And that's just pants-on-head, the same kind of thinking that led to the last big housing bust.
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@benjamin-hall So what you're saying is you should get it while the getting's good.
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The prison courtyard where the helicopter landed was the only area not protected by anti-aircraft netting. Prison union representative Martial Delabroye said that was because inmates do not use it, "except to leave the prison".
Well, okay then!
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I'm sure you all remember this:
Well....
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@dkf said in In other news today...:
@cursorkeys said in In other news today...:
The CO2 shortage is now causing massive hardships in the UK:
Where am I going to get my bit of crumpet now?
Would you settle for Krimpets? http://www.tastykake.com/products/krimpets
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@tharpa said in In other news today...:
Would you settle for Krimpets? http://www.tastykake.com/products/krimpets
That, too, sounds like something Ann Summers would stock..
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Hold my beer!
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@jbert
ToxicFatal Masculinity?
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@pjh Maybe have restorations done by competent individuals rather than the products of religious academia, I dunno...
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@jbert said in In other news today...:
Hold my beer!
FTAâŚ
Both men were married with one child
It's the modern way of things.
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@dkf said in In other news today...:
It's the modern way of things.
Still better than the traditional mostly Muslim way of things:
Both men were married
withto one child