Well, I've administered a lot of mail servers over the years, and even when I've announced an outage, it's pretty much guaranteed that I'll get a phone call within 30 seconds of taking the machine down.
I've noticed Gmail having problems quite often lately. Mostly the inbox can't load, times out, whatever. Not that I'm complaining though. It's free, and I can keep a copy back here for when they go under.:) I just don't look forward to copying my mail back up to my own server. It took about a day to bring it all down from gmail.
Aw, come on. Most of 'em don't know that you can talk to a lot of things with telnet. I've amazed people by connecting for HTTP, POP3, and IMAP using just telnet. You should see them when I send them an email, to them, from them, through their own mail server. I always get a "you can't do that!", which I always follow by "check your mail, and tell me that again."
{sigh}
It's not rocket science. It's even documented in the RFC's. Then again, most people on the Internet have never heard of an RFC, and glaze over when you start explaining it to them. At least they know how to clickie their way through putting enough bling on their MySpace page to blind almost anyone, or give epileptics seizures.
I actually had an interview at a big hosting company for a SysAdmin position, where they asked "How would you verify a site is working?". I responded "First whois hostname to make sure we're authoritative. Then nslookup hostname to make sure the ip is right. Then telnet hostname 80 GET / HTTP/1.0[enter][enter]. Then test in a browser to make sure the content is right." They looked at me, then each other to figure out if I was right, and then with a surprised look said "ok", and continued with the questioning. I guess they had a different way, like firing up a web browser and checking there. My way verifies the whole way through, but hey, they weren't looking for the best answer, they were looking for their answer, which I failed to give.
My answer to "How do you gain access to a MySQL database, if all of the passwords have been forgotten?" wasn't exactly what they expected either. That's when they started taking notes on my answers, and the questions went from interviewing to asking me for their own knowledge.
They tried to put me in the call center though, instead of only fielding hardcore admin questions. I'm too old and grumpy to be warm and friendly on stupid support calls. I'd only make it a few hours before I went ballistic on the 100th caller who said "My interwebs ain't working."
The right way to do it would be up to the folks at NASA to figure out.
I believe a deorbit burn not only decelerates them, but pushes them down too. And that burn is only 3 to 4 minutes long.
It would probably work if they were put on the upside of a curve, rather than the downside. So, they'd be gaining altitude and losing ground speed, and as they start getting pulled back down, the deceleration burn could continue pretty far down towards the atmosphere.
That calculation is way beyond my skills. Back in the day, I'm sure someone at NASA could have it figured out in less than 5 minutes with a slide rule, but now I'm sure they can just plug it into the computer, and get it back in seconds.
Doesn't anyone at NASA carry a slide rule with them any more?:)
Being that everything is extremely redundantly redundantly redundant on the shuttle, I can't suspect that they'd just have one for something essential like maneuvering.
>Only thing slow today seems to be google. Is there some sort of Level 3 outage or something? >I know Google News was down earlier in the Northeast but now it seems google video, youtube >and search are affected as well.
I wasn't sure if it was just me or not. They're distributed enough where a single provider fault shouldn't make them unavailable. I'm guessing its something bigger in their infrastructure. Even gmail isn't working for me.
I did a little looking, and it seems I'm unable to resolve their hostname on occasion. My nameservers are fine (I run mine, so I was able to verify), so it's something beyond there. Even when it resolves, it's slow as mud. Just loading the front of google.com, when it works, is pathetically slow. Oh well, it won't be my job on the line because of it. They never did decide to hire me.
"Each of the two OMS engines produces 6,000 pounds of thrust. For a typical orbiter weight, both engines together create an acceleration of approximately 2 ft/sec2 or 0.06 g's."...
"Each OMS engine is capable of 1,000 starts and 15 hours of cumulative firing. The minimum duration of an OMS engine firing is 2 seconds."
Honestly, it doesn't. But 99% of the people who want the links just want to see the pictures. If you're honestly supporting what has been a legitimate industry for centuries, that we recently decided is a bad thing, then more power to you.
I have friends that are in the industry, and I know that they're regular people. Some people look at them as lesser people, but really they aren't. I guess I have a different view, since I'm not a customer. I get to know the real person, not the showwoman side.
I guess I should have put a smiley after that last sentence.
The rear OMS engines if both fired can reduce the speed by 2 ft/s/s
A deorbit burn is a change of about 100f/s to 500f/s
They carry enough fuel for 14h of OMS thrust. This is essential, since they are automatically fired constantly during flight. They are rated for 1000 on/off cycles.
Since they say their deorbit burn is approx 3 to 4 minutes, that's just about right.
A full sustained burn, with full tanks for the OMS could change the orbital velocity by 100,800f/s in 14 hours.
Assuming your number is right, and they need to bleed off 7.5km/s, that would be 24,606 feet/second, or a 12,303 second burn, or a 205.5 minute burn, or a 3.4 hour burn.
I'm really glad you bothered to post it, because... well... I bothered to research it, and found that it's perfectly likely that they *DO* have enough fuel on board to bring their orbital velocity down to 0, and drop like a very expensive airplane shaped rock.:)
Shhhhh.. You're not suppose to let the secret out.:)
Actually, there will always be a little bit of any crime, just because you can't police everyone all the time. If I were to let some chick get with me for her left over pharmaceuticals (I'm a man whore, or so I've been told by my friends), then I could be arrested for not only prostitution but possession of illegal drugs, and she could be arrested for dealing.
Now come on, who can honestly say they haven't slept with a crack whore, and gave her a dime bag for her trouble?:)
You don't have to yell. I'm not suggesting it can be done on this mission, or even with this shuttle. It would be interesting to test, and possibly use on future craft as a contingency method for reentry.
I don't think the current shuttle design has ever run into a stall scenario. Reentry is so well planned, they can read it off the card, and if they do it right, they'll be stopped on the mark at the end of the runway.
What I was suggesting would be bringing it in, in an effective stall, which would need to be recovered from. The forward airspeed wouldn't be there, so they'd have to get it to get the control surfaces working for landing. Well, assuming something else hadn't gone wrong.
We're talking about a shuttle that has potentially failed heat shields, so I'm throwing ideas out there that could work, but as I noted in my original post, they couldn't work due to lack of planning for the scenario and lack of available fuel.
I suspect they'll simply patch the crack and land normally. If they can't, they'll send the standby shuttle up to collect everyone, and give the broken one an impossible reentry trajectory. Something like flip for the deorbit burn with the cargo bay doors open, gear down, and hatches open, and never flip back over. Make it as dirty as possible, with as many induced heat shielding failures as possible. It would come down in a blaze of glory with any surviving parts hopefully landing in the Pacific ocean. That would be a terrible shame though, but much better than the thought of a crew of astronauts being on it when it happened.
They can't just leave it up there. It's orbit will decay, and it'll come down in an unpredictable location. That's all we need is for a crippled shuttle to come down clean, nose first, into Los Angeles or New York. Well, maybe LA wouldn't a;l that be bad.:)
Actually, there were already quite a few services like Craigslist for escorts before Craigslist got big.
In many areas, the erotic services section isn't used. I've browsed around it for giggles.
I've known a few people in the industry (no, not by soliciting their services). Craigslist is generally considered a newbie trashy way to advertise. Good escorts already have better methods.
And no, I won't post any links.:) Go find them yourselves you pervs.
By forcing Craigslist to shut down their ads, it's really sent all of those providers off to other means of advertising, which means law enforcement will have to go hunting again. It was a stupid logistics idea. Law enforcement will never stop prostitution, but it looks good to the public to have a decent number of busts. Why kill your easy method of facilitating busts. It's a freakin' list of "we can arrest these people tonight", rather than really hunting them down.
It'd be like if there was a "Drug Services" section, that crack dealers were listing in. They could brag that they've increased their drug related arrests by 1000%. People will still buy and sell illegal drugs, all they can hope to do is encourage a few people out of the business, and keep the public believing that they're doing all they can do.
I don't like the idea of going to jail, so I don't deal with any industries that would put me there. I do know people who do though, so I can learn second hand of what happens. If you sit down and listen to some of these people, you'd be amazed at how well thought out some parts are. Then again, other parts are handled stupidly, and those are the people you hear about getting arrested. Some busts are just dumb luck.
It takes an awful lot more fuel to make the entire space shuttle (EFT, SRB, and orbiter) lift from the ground to orbit and gain enough speed. You're working against gravity and the atmosphere. You have to reach escape velocity.
What I was suggesting was just to slow it down. That wouldn't require anywhere near the fuel for the launch. It would just burn off some speed without dragging across the atmosphere.
But yes, they don't carry enough. If it was tested and worked, they could engineer it into future plans. It's not an impossible task, and even a rendezvous with pre-launched fuel tank would be doable. Well, if they engineered for it. They don't exactly have an easy gas door to open and refuel anything with, and an EVA to attach a fresh tank isn't in the current plans.
The shuttle is made to glide in with a nose up attitude until it encountered enough atmosphere to fly normally.
What I was suggesting was a flat drop until it reached enough air to fly in, then going to a nose down attitude to build up some forward air speed so the control surfaces could work.
Big big difference. One is flying in. One is taking a stalled glider (a really big one) and hoping to get up some airspeed to fly with.
The first one has a lot of speed to burn off in the atmosphere. The second could have a lot less if done properly.
They could save a lot of weight if they're just riding it down.
Cargo bay doors? Ejected.
Nav computers (only 3 of 5 required for normal missions)? Ejected.
Extra seats? Ejected.
Storage lockers? Ejected.
2 basket balls? Ejected.
Canada Robotic Arm? Ejected.
Post flight checklist? Nah don't need that any more. Ejected.
Landing gear? Ejected.:)
Parachutes? Nah, I'm taking those along. Ride it down to 20k feet, and jump out of the cargo bay.
Hmmm.. They DO have parachutes now, don't they? They're used in case of low altitude failure, where they can jump out the lower door.
Think about what I was explaining, don't get stuck on one word.
Take a nice fast space shuttle, and bring it to 0 ground speed. Not fly up to a stable geosynchronous orbit. If you go UP, you're going the wrong way to come DOWN. As it falls and the air thickens, it'll slow down. The shuttle wasn't exactly made for it, which is why I said the other parts. It's not exactly a practical plan, but it could have been used as a contingency plan. Now their contingency plan is to launch another shuttle which at the odds will likely have a fault too.
That's about all the Buran had. It was my understanding that they only had a partially assembled life support system and the onboard displays were nonfunctional on it's flight.
More as in geosynchronous - traveling synchronous with the geo (ground/earth). It would just fail to maintain it's orbit, but that's the idea.:)
0 forward velocity means less friction against the air. Zinging anything across the atmosphere really quickly will... well... make a lot of friction, and as it flies through the thinner parts of the atmosphere, it will get hot and not slow very well.
No, I really meant down into a geosynchronous orbit.:)
At a low orbit with 0 ground speed, the orbit will decay fast, which is what you'd want. If it went up to where it could maintain that orbit, well, it wouldn't come down very easily.
Basically, do a burn similar to their deorbit burn. Spin it around backwards, fire the main engines for about 4 minutes, flip back around, and fly home.:)
When they do the deorbit burn, they slow down by about 150mph, and the orbit decays rapidly.
They don't carry enough fuel to bring that down to 0 though.
I went looking around, and found that there was a proposal a long time ago for basically a bean bag that an astronaut could climb into. More like a big foam filled sleeping bag. It had minimal heat shielding, but if they were dropped geosynchronous, they could make it back. It'd take about 4 hours or so, trapped inside a little bag, with no light, no communications, nothing. They'd just lay in it and wonder if they were going to survive. It was dropped because of the potential psychological effects, and they never tested it from a real altitude. The only "test" was throwing a crash dummy in the bag from a bridge.
Slashdot Mirror
Well, I've administered a lot of mail servers over the years, and even when I've announced an outage, it's pretty much guaranteed that I'll get a phone call within 30 seconds of taking the machine down.
I've noticed Gmail having problems quite often lately. Mostly the inbox can't load, times out, whatever. Not that I'm complaining though. It's free, and I can keep a copy back here for when they go under. :) I just don't look forward to copying my mail back up to my own server. It took about a day to bring it all down from gmail.
In comments from Google Admins, they said "oops." :)
Aw, come on. Most of 'em don't know that you can talk to a lot of things with telnet. I've amazed people by connecting for HTTP, POP3, and IMAP using just telnet. You should see them when I send them an email, to them, from them, through their own mail server. I always get a "you can't do that!", which I always follow by "check your mail, and tell me that again."
{sigh}
It's not rocket science. It's even documented in the RFC's. Then again, most people on the Internet have never heard of an RFC, and glaze over when you start explaining it to them. At least they know how to clickie their way through putting enough bling on their MySpace page to blind almost anyone, or give epileptics seizures.
I actually had an interview at a big hosting company for a SysAdmin position, where they asked "How would you verify a site is working?". I responded "First whois hostname to make sure we're authoritative. Then nslookup hostname to make sure the ip is right. Then telnet hostname 80 GET / HTTP/1.0[enter][enter]. Then test in a browser to make sure the content is right." They looked at me, then each other to figure out if I was right, and then with a surprised look said "ok", and continued with the questioning. I guess they had a different way, like firing up a web browser and checking there. My way verifies the whole way through, but hey, they weren't looking for the best answer, they were looking for their answer, which I failed to give.
My answer to "How do you gain access to a MySQL database, if all of the passwords have been forgotten?" wasn't exactly what they expected either. That's when they started taking notes on my answers, and the questions went from interviewing to asking me for their own knowledge.
They tried to put me in the call center though, instead of only fielding hardcore admin questions. I'm too old and grumpy to be warm and friendly on stupid support calls. I'd only make it a few hours before I went ballistic on the 100th caller who said "My interwebs ain't working."
The right way to do it would be up to the folks at NASA to figure out.
I believe a deorbit burn not only decelerates them, but pushes them down too. And that burn is only 3 to 4 minutes long.
It would probably work if they were put on the upside of a curve, rather than the downside. So, they'd be gaining altitude and losing ground speed, and as they start getting pulled back down, the deceleration burn could continue pretty far down towards the atmosphere.
That calculation is way beyond my skills. Back in the day, I'm sure someone at NASA could have it figured out in less than 5 minutes with a slide rule, but now I'm sure they can just plug it into the computer, and get it back in seconds.
Doesn't anyone at NASA carry a slide rule with them any more? :)
A fully loaded tank.
How many tanks of fuel do they carry?
Being that everything is extremely redundantly redundantly redundant on the shuttle, I can't suspect that they'd just have one for something essential like maneuvering.
Yup. I'd have to assume that if they can do a 15 hour burn, that would imply that they carry enough for a 15 hour burn at launch.
But, I don't work for NASA either, so I don't have those juicy little tidbits. I can't exactly check on their fuel status. :)
>Only thing slow today seems to be google. Is there some sort of Level 3 outage or something?
>I know Google News was down earlier in the Northeast but now it seems google video, youtube
>and search are affected as well.
I wasn't sure if it was just me or not. They're distributed enough where a single provider fault shouldn't make them unavailable. I'm guessing its something bigger in their infrastructure. Even gmail isn't working for me.
I did a little looking, and it seems I'm unable to resolve their hostname on occasion. My nameservers are fine (I run mine, so I was able to verify), so it's something beyond there. Even when it resolves, it's slow as mud. Just loading the front of google.com, when it works, is pathetically slow. Oh well, it won't be my job on the line because of it. They never did decide to hire me.
Ya, I get a lot of that down here. Something about the whole fire and brimstone atmosphere.
How about (pdf), pg 3.
"Each of the two OMS engines produces 6,000 ...
pounds of thrust. For a typical orbiter weight,
both engines together create an acceleration of
approximately 2 ft/sec2 or 0.06 g's."
"Each OMS engine is capable of 1,000 starts and
15 hours of cumulative firing. The minimum
duration of an OMS engine firing is 2 seconds."
I actually do know most of the keywords. But there isn't a section named "altered state services" :)
Honestly, it doesn't. But 99% of the people who want the links just want to see the pictures. If you're honestly supporting what has been a legitimate industry for centuries, that we recently decided is a bad thing, then more power to you.
I have friends that are in the industry, and I know that they're regular people. Some people look at them as lesser people, but really they aren't. I guess I have a different view, since I'm not a customer. I get to know the real person, not the showwoman side.
I guess I should have put a smiley after that last sentence.
I did a little reading....
The rear OMS engines if both fired can reduce the speed by 2 ft/s/s
A deorbit burn is a change of about 100f/s to 500f/s
They carry enough fuel for 14h of OMS thrust. This is essential, since they are automatically fired constantly during flight. They are rated for 1000 on/off cycles.
Since they say their deorbit burn is approx 3 to 4 minutes, that's just about right.
A full sustained burn, with full tanks for the OMS could change the orbital velocity by 100,800f/s in 14 hours.
Assuming your number is right, and they need to bleed off 7.5km/s, that would be 24,606 feet/second,
or a 12,303 second burn,
or a 205.5 minute burn,
or a 3.4 hour burn.
I'm really glad you bothered to post it, because ... well ... I bothered to research it, and found that it's perfectly likely that they *DO* have enough fuel on board to bring their orbital velocity down to 0, and drop like a very expensive airplane shaped rock. :)
Shhhhh.. You're not suppose to let the secret out. :)
Actually, there will always be a little bit of any crime, just because you can't police everyone all the time. If I were to let some chick get with me for her left over pharmaceuticals (I'm a man whore, or so I've been told by my friends), then I could be arrested for not only prostitution but possession of illegal drugs, and she could be arrested for dealing.
Now come on, who can honestly say they haven't slept with a crack whore, and gave her a dime bag for her trouble? :)
You don't have to yell. I'm not suggesting it can be done on this mission, or even with this shuttle. It would be interesting to test, and possibly use on future craft as a contingency method for reentry.
I don't think the current shuttle design has ever run into a stall scenario. Reentry is so well planned, they can read it off the card, and if they do it right, they'll be stopped on the mark at the end of the runway.
What I was suggesting would be bringing it in, in an effective stall, which would need to be recovered from. The forward airspeed wouldn't be there, so they'd have to get it to get the control surfaces working for landing. Well, assuming something else hadn't gone wrong.
We're talking about a shuttle that has potentially failed heat shields, so I'm throwing ideas out there that could work, but as I noted in my original post, they couldn't work due to lack of planning for the scenario and lack of available fuel.
I suspect they'll simply patch the crack and land normally. If they can't, they'll send the standby shuttle up to collect everyone, and give the broken one an impossible reentry trajectory. Something like flip for the deorbit burn with the cargo bay doors open, gear down, and hatches open, and never flip back over. Make it as dirty as possible, with as many induced heat shielding failures as possible. It would come down in a blaze of glory with any surviving parts hopefully landing in the Pacific ocean. That would be a terrible shame though, but much better than the thought of a crew of astronauts being on it when it happened.
They can't just leave it up there. It's orbit will decay, and it'll come down in an unpredictable location. That's all we need is for a crippled shuttle to come down clean, nose first, into Los Angeles or New York. Well, maybe LA wouldn't a;l that be bad. :)
Actually, there were already quite a few services like Craigslist for escorts before Craigslist got big.
In many areas, the erotic services section isn't used. I've browsed around it for giggles.
I've known a few people in the industry (no, not by soliciting their services). Craigslist is generally considered a newbie trashy way to advertise. Good escorts already have better methods.
And no, I won't post any links. :) Go find them yourselves you pervs.
By forcing Craigslist to shut down their ads, it's really sent all of those providers off to other means of advertising, which means law enforcement will have to go hunting again. It was a stupid logistics idea. Law enforcement will never stop prostitution, but it looks good to the public to have a decent number of busts. Why kill your easy method of facilitating busts. It's a freakin' list of "we can arrest these people tonight", rather than really hunting them down.
It'd be like if there was a "Drug Services" section, that crack dealers were listing in. They could brag that they've increased their drug related arrests by 1000%. People will still buy and sell illegal drugs, all they can hope to do is encourage a few people out of the business, and keep the public believing that they're doing all they can do.
I don't like the idea of going to jail, so I don't deal with any industries that would put me there. I do know people who do though, so I can learn second hand of what happens. If you sit down and listen to some of these people, you'd be amazed at how well thought out some parts are. Then again, other parts are handled stupidly, and those are the people you hear about getting arrested. Some busts are just dumb luck.
It takes an awful lot more fuel to make the entire space shuttle (EFT, SRB, and orbiter) lift from the ground to orbit and gain enough speed. You're working against gravity and the atmosphere. You have to reach escape velocity.
What I was suggesting was just to slow it down. That wouldn't require anywhere near the fuel for the launch. It would just burn off some speed without dragging across the atmosphere.
But yes, they don't carry enough. If it was tested and worked, they could engineer it into future plans. It's not an impossible task, and even a rendezvous with pre-launched fuel tank would be doable. Well, if they engineered for it. They don't exactly have an easy gas door to open and refuel anything with, and an EVA to attach a fresh tank isn't in the current plans.
The shuttle is made to glide in with a nose up attitude until it encountered enough atmosphere to fly normally.
What I was suggesting was a flat drop until it reached enough air to fly in, then going to a nose down attitude to build up some forward air speed so the control surfaces could work.
Big big difference. One is flying in. One is taking a stalled glider (a really big one) and hoping to get up some airspeed to fly with.
The first one has a lot of speed to burn off in the atmosphere. The second could have a lot less if done properly.
You didn't reference my first post, did you? Follow the parents up to it.
That sounds an awful lot like what I said. :)
Yes they do. :)
It's the ICES Inflight Crew Escape System (ICES)
Maybe they'll cocnsider it in the future.
They could save a lot of weight if they're just riding it down.
Cargo bay doors? Ejected. :)
Nav computers (only 3 of 5 required for normal missions)? Ejected.
Extra seats? Ejected.
Storage lockers? Ejected.
2 basket balls? Ejected.
Canada Robotic Arm? Ejected.
Post flight checklist? Nah don't need that any more. Ejected.
Landing gear? Ejected.
Parachutes? Nah, I'm taking those along. Ride it down to 20k feet, and jump out of the cargo bay.
Hmmm.. They DO have parachutes now, don't they? They're used in case of low altitude failure, where they can jump out the lower door.
Think about what I was explaining, don't get stuck on one word.
Take a nice fast space shuttle, and bring it to 0 ground speed. Not fly up to a stable geosynchronous orbit. If you go UP, you're going the wrong way to come DOWN. As it falls and the air thickens, it'll slow down. The shuttle wasn't exactly made for it, which is why I said the other parts. It's not exactly a practical plan, but it could have been used as a contingency plan. Now their contingency plan is to launch another shuttle which at the odds will likely have a fault too.
Hehe.
That's about all the Buran had. It was my understanding that they only had a partially assembled life support system and the onboard displays were nonfunctional on it's flight.
More as in geosynchronous - traveling synchronous with the geo (ground/earth). It would just fail to maintain it's orbit, but that's the idea. :)
0 forward velocity means less friction against the air. Zinging anything across the atmosphere really quickly will ... well ... make a lot of friction, and as it flies through the thinner parts of the atmosphere, it will get hot and not slow very well.
No, I really meant down into a geosynchronous orbit. :)
At a low orbit with 0 ground speed, the orbit will decay fast, which is what you'd want. If it went up to where it could maintain that orbit, well, it wouldn't come down very easily.
Basically, do a burn similar to their deorbit burn. Spin it around backwards, fire the main engines for about 4 minutes, flip back around, and fly home. :)
When they do the deorbit burn, they slow down by about 150mph, and the orbit decays rapidly.
They don't carry enough fuel to bring that down to 0 though.
I went looking around, and found that there was a proposal a long time ago for basically a bean bag that an astronaut could climb into. More like a big foam filled sleeping bag. It had minimal heat shielding, but if they were dropped geosynchronous, they could make it back. It'd take about 4 hours or so, trapped inside a little bag, with no light, no communications, nothing. They'd just lay in it and wonder if they were going to survive. It was dropped because of the potential psychological effects, and they never tested it from a real altitude. The only "test" was throwing a crash dummy in the bag from a bridge.