Virgin Galactic successfully flies tourists to space for first time(theguardian.com)
theguardian.com
Virgin Galactic successfully flies tourists to space for first time
https://www.theguardian.com/science/2023/aug/10/vigin-galactic-space-flight-vss-unity-landing
126 comments
When I first watched the XPrize flight in 2004 (!!) on a tiny pixelated video over an ISDN connection, I thought we would only be a couple of years away from regular space tourism. I never would have dreamt that chatbots would pass the Turing test before Virgin Galactic became operational. Predicting technological advancements is hard.
I had just joined a large investment bank and was in NYC for training when I heard that the XPrize flight had succeeded. Although finance has been my career, I grew up wanting to be an astronaut and closely follow space science. I also expected that suborbital manned tourism flights would become routine, and that in time SpaceShipOne and similar designs would be scaled up to reach orbit.
Although the latter didn't happen, I am glad that SpaceX came along and made reusing (!) rockets that land at their own launch pads (!!) routine. It is not impossible that I will someday ride Starship or a descendant to orbit.
Although the latter didn't happen, I am glad that SpaceX came along and made reusing (!) rockets that land at their own launch pads (!!) routine. It is not impossible that I will someday ride Starship or a descendant to orbit.
I really don’t think our current crop of chat bots can pass a Turing test.
https://news.ycombinator.com/item?id=37057043
The main issues with gpt and the Turing test are not that it isn’t smart enough but rather that fine tuning for helpfulness and harmlessness has turned it into a Quokka.
Completely harmless and naive in its attitudes towards harmful or controversial things, and this is trivially detectable.
Completely harmless and naive in its attitudes towards harmful or controversial things, and this is trivially detectable.
This is a bit like saying that none of our current crop of computers are Turing complete, because their tape isn't infinite.
We will never achieve a theoretically perfect Turing machine, or a program indistinguishable from a real human in every single respect including funny edge cases. But we can get close enough that it's meaningful to use the theoretical ideal in a colloquial sense that means "crosses the threshold in most contexts". GPT models can actually keep up a half-decent facade against a suspicious interlocutor for a while, something no program has ever done before.
We will never achieve a theoretically perfect Turing machine, or a program indistinguishable from a real human in every single respect including funny edge cases. But we can get close enough that it's meaningful to use the theoretical ideal in a colloquial sense that means "crosses the threshold in most contexts". GPT models can actually keep up a half-decent facade against a suspicious interlocutor for a while, something no program has ever done before.
I agree the software is doing better than ever before! However it still has serious shortcomings which is an active area of research. An AI researcher familiar with these issues could probably make an accurate detection in under one minute, so I don’t think this is an “infinite tape” issue this is simply an issue of performance. They are pretty good and they will get better, but I believe a true AGI would be able to mimic a human to properly pass the test.
That's entirely fair. It definitely feels like some sort of threshold has been crossed, and the only term we have for this performance axis is "the Turing test", but you're absolutely right that LLMs are very far from perfect. It feels more like the beginning of a journey rather than the end. We should probably get in the habit of treating Turing Test performance as more like a continuous scale rather than a pass/fail condition.
Cutting edge bots fail because they are too perfect to be human.
Actually I think they make weird choices sometimes that could be tested for systematically if someone knew which model it was and had some time with it before the Turing test took place.
None of those examples are GPT-4
I paid for GPT-4 and noticed some weird behavior that seemed reproducible, so you could test for those things to reveal if you’re talking to a person or a chatbot. Biggest thing is you can ask it for a story of someone’s childhood (you can’t ask it for its childhood) and it will provide a plausible sounding but not internally consistent story.
You can also just ask it what time it is, or what day it is, or how much time has elapsed since your last message. It doesn't know any of these.
That's an incredibly stupid Turing test, and you know it.
If the robot cannot answer that question it is simple and effective test. The whole point of a turing test is that you cannot distinguish between a person and a robot. If you can wait one minute and then ask it how long it has been since your last request this sounds like a simple and effective test.
Do you seriously think it would be hard for OpenAI to give GPT-4 a timer? The point of a Turing test is a passive evaluation of how intelligent a bot is. It's not a test that OpenAI is trying to pass.
You misunderstand me. To me, a Turing test is passed when the interviewer cannot distinguish between a robot and a human. If OpenAI were to add a special timer function to GPT-4, then that specific question would no longer work to tell the difference, but that specific question is just one example of many types of questions one can use to tell that GPT-4 is not a human. GPT-4 with a clock does not change the fact that there are many ways to tell it is not human.
> The point of a Turing test is a passive evaluation of how intelligent a bot is.
I don't know what "the point" of the test is (that is subjective) but I know how the test works. You create a system where a tester and a subject can pass messages to each other but cannot see each other (so a chat system is great for this) and then the tester tries to determine if the subject is a robot or a person. If the tester cannot tell if the subject is a human or a robot, the robot has passed the test. Many people have pointed out the test is not necessarily useful for evaluating AI! An AGI may be extremely intelligent and useful and still not pass the Turing test, but it would nonetheless be true that it did not pass. However a highly intelligent AGI would probably be good at pretending to be a human.
> It's not a test that OpenAI is trying to pass.
We are in agreement on this. They are not trying to pass this test and their current system can not pass it. This is why I say the current system cannot pass a Turing test. I am not talking about a theoretical future system!
> The point of a Turing test is a passive evaluation of how intelligent a bot is.
I don't know what "the point" of the test is (that is subjective) but I know how the test works. You create a system where a tester and a subject can pass messages to each other but cannot see each other (so a chat system is great for this) and then the tester tries to determine if the subject is a robot or a person. If the tester cannot tell if the subject is a human or a robot, the robot has passed the test. Many people have pointed out the test is not necessarily useful for evaluating AI! An AGI may be extremely intelligent and useful and still not pass the Turing test, but it would nonetheless be true that it did not pass. However a highly intelligent AGI would probably be good at pretending to be a human.
> It's not a test that OpenAI is trying to pass.
We are in agreement on this. They are not trying to pass this test and their current system can not pass it. This is why I say the current system cannot pass a Turing test. I am not talking about a theoretical future system!
It’s not so stupid in the context of a LLM that is good at summarizing but bad at common sense.
Atoms are harder than bits. I'm no longer surprised anymore when software advances break through while hardware advances like self driving cars and humanoid robotics languish, because the real world really is much messier than moving data around.
Software scales better than hardware, so most investment (capital and intellectual) is in software.
ML advancements wouldn't have been possible without the extreme progress in hardware. It's not a hardware vs software thing, rather it's a function of demand. The business model of space tourism in general was always dubious.
Although in case of SS2 in particular, it also got delayed by the experimental nature of its hybrid engine (they changed fuels and redesigned it several times) as well as their approach to safety (2014 disaster).
Although in case of SS2 in particular, it also got delayed by the experimental nature of its hybrid engine (they changed fuels and redesigned it several times) as well as their approach to safety (2014 disaster).
>Following liftoff, Virgin Galactic’s carrier plane VMS Eve transported VSS Unity to an altitude of about 50,000ft. Eve then dropped Unity which then fired its own rocket motor and ascended to suborbital space. Passengers aboard experienced approximately 3Gs.
suborbital, would still be an amazing experience though.
suborbital, would still be an amazing experience though.
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Is it feasible for them to build an orbital version?
I want the concept of launching from altitude to work because it seems like the heavy atmosphere part has different requirements and so having another vehicle to help with that seems intuitive.
I also wonder if you could make orbital flight with this type of system more achievable if the delivery aircraft and/or the rocket had scramjet ability so that it was more efficient.
I want the concept of launching from altitude to work because it seems like the heavy atmosphere part has different requirements and so having another vehicle to help with that seems intuitive.
I also wonder if you could make orbital flight with this type of system more achievable if the delivery aircraft and/or the rocket had scramjet ability so that it was more efficient.
> I want the concept of launching from altitude to work because it seems like the heavy atmosphere part has different requirements and so having another vehicle to help with that seems intuitive.
This is essentially what multi-stage rockets are. Only the lowest stage is optimized for heavy atmosphere.
The "dropping from a plane" thing is theoretically a good idea. Wings and jets save lots of fuel. But in practice one needs a hilariously large plane to carry a modest rocket, and it needs to be hypersonic to really give the dropped rocket a good orbital kick, and the linkage between the rocket/plane needs to not blow up. Historically... You mind as well build a massive vertical first stage.
You could strap jets to a first stage and try to reuse it. Hello KSP!
This is essentially what multi-stage rockets are. Only the lowest stage is optimized for heavy atmosphere.
The "dropping from a plane" thing is theoretically a good idea. Wings and jets save lots of fuel. But in practice one needs a hilariously large plane to carry a modest rocket, and it needs to be hypersonic to really give the dropped rocket a good orbital kick, and the linkage between the rocket/plane needs to not blow up. Historically... You mind as well build a massive vertical first stage.
You could strap jets to a first stage and try to reuse it. Hello KSP!
Nope.
As a point of comparison, the orbital velocity of ISS is 17,000 mph.
The max speed of Unity was given as Mach 2.88. The speed of sound varies from 340 m/s at sea level to 200 m/s at 120,000 feet. So Mach 2.88 would correspond to somewhere between 1000 - 2000 mph depending on where it was attained.
To enter orbit, a vehicle must be simultaneously at orbital altitude _and_ at orbital velocity (in the correct direction).
Furthermore, note that quoting speed as a Mach number is fundamentally only relevant to atmospheric flight. Mach number is referenced to the speed of sound, and sound does not travel in the vacuum of space.
The Virgin Galactic vehicle shoots up to very high altitude but then simply falls back to earth.
As a point of comparison, the orbital velocity of ISS is 17,000 mph.
The max speed of Unity was given as Mach 2.88. The speed of sound varies from 340 m/s at sea level to 200 m/s at 120,000 feet. So Mach 2.88 would correspond to somewhere between 1000 - 2000 mph depending on where it was attained.
To enter orbit, a vehicle must be simultaneously at orbital altitude _and_ at orbital velocity (in the correct direction).
Furthermore, note that quoting speed as a Mach number is fundamentally only relevant to atmospheric flight. Mach number is referenced to the speed of sound, and sound does not travel in the vacuum of space.
The Virgin Galactic vehicle shoots up to very high altitude but then simply falls back to earth.
No, it can't even come close to reaching orbital velocity. Fundamentally it's just a plane with a rocket motor on it that can go up and back down; something which could orbit and deorbit would be a completely different vehicle entirely.
You may be interested in skulon https://en.m.wikipedia.org/wiki/Skylon_(spacecraft)
From the Wikipedia page: "It could carry X tonnes of cargo [...] over 24% more than SpaceX Falcon 9 launch vehicle in reusable mode"
Lol, one small difference tho, one exists in the real world, the other one in the minds of a few British peeps.
Lol, one small difference tho, one exists in the real world, the other one in the minds of a few British peeps.
they did prove the precooler work though
I hope it is fully realized in the future. Seems amazing.
>I want the concept of launching from altitude to work because it seems like the heavy atmosphere part has different requirements and so having another vehicle to help with that seems intuitive.
This is what they tried and failed with Virgin Orbit. The economics of plane launch just don't work out versus the logistical hassle of it.
This is what they tried and failed with Virgin Orbit. The economics of plane launch just don't work out versus the logistical hassle of it.
Not an expert but as far as I know, orbital is way, way more difficult. You need to reach speeds several times higher and then also deal with reentry
No. It is slower than MiG-31
This article carefully avoids mentioning how high they went, is there any information on what actual altitude they reached during the flight?
Space.com's coverage includes the specific altitude [1], listing 88.4 km: "The space plane reached a maximum speed of about Mach 2.9 on Galactic-02 — 2.9 times the speed of sound — and a peak altitude of 290,000 feet (88.4 kilometers) before heading back down to Earth. It aced a runway touchdown at Spaceport America around 11:32 a.m. EDT (1532 GMT)."
This tracks with CBC News's estimate [2], which reports that the flight generally reaches an altitude of "more than 80 kilometres up," though the CBC's report does not include altitude numbers specific to this flight.
[1] https://www.space.com/virgin-galactic-galactic02-launch-succ...
[2] https://www.cbc.ca/news/science/virgin-galactic-tourists-1.6...
This tracks with CBC News's estimate [2], which reports that the flight generally reaches an altitude of "more than 80 kilometres up," though the CBC's report does not include altitude numbers specific to this flight.
[1] https://www.space.com/virgin-galactic-galactic02-launch-succ...
[2] https://www.cbc.ca/news/science/virgin-galactic-tourists-1.6...
Then they shouldn't be using 'space' in the title.
If they're going to dilute that term then what's the point in having it in the first place.
If they're going to dilute that term then what's the point in having it in the first place.
This is going to be like hackers vs. crackers. We're going to try to fight for space to be > 100km and astronauts to be people who've been to space and we're going to fail. Especially since space in the US sometimes means > 80km and hence astronauts are people above 80km.
I think we need a word for someone who's gone orbital into space.
I think we need a word for someone who's gone orbital into space.
Even aside from altitude and orbital vs sub-orbital, the term astronauts needs to refer to people who made a career out of going into and working in and with space flight. The people who pay money to go for a visit are tourists, nothing more. You wouldn't call someone who takes a 7-day cruise a sailor.
> You wouldn't call someone who takes a 7-day cruise a sailor.
I wouldn't and you wouldn't and perhaps no one should, but coincidentally, Virgin Voyages cruise line does indeed call their customers "sailors":
https://www.virginvoyages.com/help-and-support/the-days-at-s...
I wouldn't and you wouldn't and perhaps no one should, but coincidentally, Virgin Voyages cruise line does indeed call their customers "sailors":
https://www.virginvoyages.com/help-and-support/the-days-at-s...
At least they're consistent.
The comparison I like to use is that being a passenger on an airplane doesn't make someone an aviator.
Shall we revive the Soviet-era "cosmonaut?" By the way, For All Mankind is a great show.
FWIW cosmonaut isn’t Soviet era, it's the Russian term for astronaut.
Though I've never understood why in the West we use that essentially untranslated term* when we don't anglicize the Russian pronunciation of any other jobs. You won't read a news article about Russian "svarshchiks", you'd just translate that to "welder".
* And now taikonaut for Chinese astronauts!
Though I've never understood why in the West we use that essentially untranslated term* when we don't anglicize the Russian pronunciation of any other jobs. You won't read a news article about Russian "svarshchiks", you'd just translate that to "welder".
* And now taikonaut for Chinese astronauts!
You can't "revive" it because it is not dead
“Space” has a relatively arbitrary definition and these tourists vehicles have been designed to reach it just barely. Fun experience but they have little in common with orbital rockets.
On the live stream I saw them go above 290,000 feet (88 km). So, below the Kármán line by quite a bit.
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> Galactic 02 is a suborbital flight. However, despite VSS Unity not reaching orbit, the trajectory allows passengers to experience several minutes of weightlessness at an altitude high enough for them to see the Earth’s curvature
Glad they acknowledged that, never realized how close commercial airplane flights were to that
Glad they acknowledged that, never realized how close commercial airplane flights were to that
Not quite. :) The Conorde flew at 60,000 ft and modern corporate jets can get up to 50,000ft.
For comparison, the SR-71 flew at 85,000 ft.
For comparison, the SR-71 flew at 85,000 ft.
Oh okay then thats pathetic
I see a lot of discussion/arguments on the definition of space here. Allow me to fill in few relevant details of how "space" is defined.
There is no clear definition of a boundary between space and not-space. Some like to use the definition of "space" as "no-meaningful atmosphere". Note that the atmosphere does extended very far indeed into what we typically deem "space". Typically we model gases (like the atmosphere) as discrete packets of continuous properties. If density is below a very low threshold, we can't do that, and have to model gases using rarified models (where gas behaves more like individual particles). If we use the 1976 Standard Atmosphere model this happens at above 86km. Therefore to atmospheric scientists, space is 86km.
Now let's say you're building an orbital space plane. To stay aloft, your gravity opposing forces come from two sources: aerodynamic lift and centrifugal force. When you go faster, both forces increase, so for every altitude, there's a speed which keeps you aloft. However lift force is a function of density, and density drops with altitude. Therefore there is a point where aerodynamic lift is essentially meaningless compared with the centrifugal. At this point, you are more of a orbital vehicle than an aerodynamic one, so we can say that you are "in orbit". This altitude is The Kalman line. The important thing to note is that the Kalman Line is a definition prescribed to a specific vehicle (the Bell X-2, although it is rarely discussed in that context). Changing the weight and lift properties change it. Hence the boundary is very fuzzy and the exact source of definition changes depending on how it's calculated. It's also been calculated based on aerothermal heating considerations, and based on the operational limits of air-breathing engines. Therefore, it's been cited as 83km, 86km, 90km and 100km depending on the specific source. A key takeaway here is that The Kalman Line is a speed as well as an altitude, so it doesn't even make sense to use this as a boundary in a suborbital context. But for orbital scientists/engineers, you safely say that's space is not below 80km, and certainly above 100km.
Now imagine you are the US Air force and some of your pilots flew an experimental aircraft (the X-15) 90km altitude, and you want to put astronaut wings on them to gain some inter-service rivalry clout. Well for you, the definition of space is then 90km.
Now let's say you are the FAA and want to quantify where your jurisdiction ends. Well, pick an arbitrary definition based on Kalman's notes. 100km should be good enough for your needs.
Now let's say you are a satellite engineer and want a definition where your satellites will actually stay in orbit for a few trips around the earth without thrust corrections. Pretty hard to do at 80km, there's too much air. As it turns out the lowest sustained circular orbits occur at around 125 km. So 125 km is a good definition of space for you.
There's some much needed historical context. Now let the useless arguments surrounding the pedantry of fuzzy definitions continue.
There is no clear definition of a boundary between space and not-space. Some like to use the definition of "space" as "no-meaningful atmosphere". Note that the atmosphere does extended very far indeed into what we typically deem "space". Typically we model gases (like the atmosphere) as discrete packets of continuous properties. If density is below a very low threshold, we can't do that, and have to model gases using rarified models (where gas behaves more like individual particles). If we use the 1976 Standard Atmosphere model this happens at above 86km. Therefore to atmospheric scientists, space is 86km.
Now let's say you're building an orbital space plane. To stay aloft, your gravity opposing forces come from two sources: aerodynamic lift and centrifugal force. When you go faster, both forces increase, so for every altitude, there's a speed which keeps you aloft. However lift force is a function of density, and density drops with altitude. Therefore there is a point where aerodynamic lift is essentially meaningless compared with the centrifugal. At this point, you are more of a orbital vehicle than an aerodynamic one, so we can say that you are "in orbit". This altitude is The Kalman line. The important thing to note is that the Kalman Line is a definition prescribed to a specific vehicle (the Bell X-2, although it is rarely discussed in that context). Changing the weight and lift properties change it. Hence the boundary is very fuzzy and the exact source of definition changes depending on how it's calculated. It's also been calculated based on aerothermal heating considerations, and based on the operational limits of air-breathing engines. Therefore, it's been cited as 83km, 86km, 90km and 100km depending on the specific source. A key takeaway here is that The Kalman Line is a speed as well as an altitude, so it doesn't even make sense to use this as a boundary in a suborbital context. But for orbital scientists/engineers, you safely say that's space is not below 80km, and certainly above 100km.
Now imagine you are the US Air force and some of your pilots flew an experimental aircraft (the X-15) 90km altitude, and you want to put astronaut wings on them to gain some inter-service rivalry clout. Well for you, the definition of space is then 90km.
Now let's say you are the FAA and want to quantify where your jurisdiction ends. Well, pick an arbitrary definition based on Kalman's notes. 100km should be good enough for your needs.
Now let's say you are a satellite engineer and want a definition where your satellites will actually stay in orbit for a few trips around the earth without thrust corrections. Pretty hard to do at 80km, there's too much air. As it turns out the lowest sustained circular orbits occur at around 125 km. So 125 km is a good definition of space for you.
There's some much needed historical context. Now let the useless arguments surrounding the pedantry of fuzzy definitions continue.
Minor nitpick, but it's the "Kármán Line", not the Kalman line. Named after Theodore von Kármán, who calculated the limit of atmospheric flight.
Additionally, in orbit there is no force opposing gravity, so your description is somewhat inaccurate in its premise if not the point.
Additionally, in orbit there is no force opposing gravity, so your description is somewhat inaccurate in its premise if not the point.
I wrote this post when I've supposed to be working on some Kalman Filter models at work, and it really shows.
> Additionally, in orbit there is no force opposing gravity
There is when we treat the vehicle in a rotating reference frame centered around the earth origin, as is typically done for orbital calculations. It is completely correct to treat the vehicle in such a manner. And is of course exactly how the Karman Line was first proposed to be calculated.
> Additionally, in orbit there is no force opposing gravity
There is when we treat the vehicle in a rotating reference frame centered around the earth origin, as is typically done for orbital calculations. It is completely correct to treat the vehicle in such a manner. And is of course exactly how the Karman Line was first proposed to be calculated.
Gravity is a centripetal force that is constantly accelerating an orbiting body towards the orbited body. There is no counter-force that cancels it out. An object traveling in a circle is constantly accelerating, and by F=MA must have a force constantly acting against it.
You can use coordinate frames to magick up some imaginary force that explains what happens in a limited, non-inertial frame, but that does not mean the force exists. There is no magical force that appears to lift an object up and away from the Earth once it's traveling fast enough.
I've never once used an imaginary centrifugal force in any of my orbital calclulations, for what it's worth.
You can use coordinate frames to magick up some imaginary force that explains what happens in a limited, non-inertial frame, but that does not mean the force exists. There is no magical force that appears to lift an object up and away from the Earth once it's traveling fast enough.
I've never once used an imaginary centrifugal force in any of my orbital calclulations, for what it's worth.
After doing some cursory Google searches on relative motion in orbit, establishing a rotating frame seems standard to me. Even the original Clohessy-Wiltshire paper[1] starts by doing that.
As a physicist, though admittedly not working in orbital mechanics, I can assure you working with non-inertial frames and their concomitant pseudoforces is nothing out of the ordinary. Whether or not these forces are "magical" or even "real" is more of a philosophical question, secondary to the fact of their utility.
1: https://arc.aiaa.org/doi/10.2514/8.8704
As a physicist, though admittedly not working in orbital mechanics, I can assure you working with non-inertial frames and their concomitant pseudoforces is nothing out of the ordinary. Whether or not these forces are "magical" or even "real" is more of a philosophical question, secondary to the fact of their utility.
1: https://arc.aiaa.org/doi/10.2514/8.8704
Appreciate the link! I actually dabbled with Clohessy-Wiltshire equations in some higher-level orbital classes years ago. I haven't done anything with spacecraft rendezvous since college so it definitely fell off my radar.
As for the "existence" of the force, I suppose you're right in that it can get quite philosophical, as even our "Earth-Centered Inertial" reference frame isn't truly inertial.
As for the "existence" of the force, I suppose you're right in that it can get quite philosophical, as even our "Earth-Centered Inertial" reference frame isn't truly inertial.
I swear to God, the amount of misunderstanding around the concept of centrifugal force is insane. Relevant XKCD by the way: https://xkcd.com/123/
Sometimes it's more convenient to do physics in a rotating reference frame. There's nothing magical about it. For the given problem of predicting whether or not a vehicle held steady above Earth by a combination of both it's "Keplerian Force" and it's aerodynamic lift, converting to a rotating reference frame makes the math very easy. It's perfectly fine to conceptualize physics likes this. You could also think of it in an inertial frame. That's fine. Go ahead. But one isn't more correct than the other.
> I've never once used an imaginary centrifugal force in any of my orbital calculations, for what it's worth.
The equation for determining an orbital speed for given altitude can be derived from an inertial reference frame calculating the acceleration required to sustain circular motion or from a force balance in a rotating reference frame. You can start from first principles given either and derive the exact same equation. So you could choose to if you so desired. And again, as per the above example, sometimes considering the rotating frame makes the problem more intuitive. Neither is more correct than the other. Strict doctrine to one as being "more correct" only limits understanding of how problems can be solved.
> I've never once used an imaginary centrifugal force in any of my orbital calculations, for what it's worth.
The equation for determining an orbital speed for given altitude can be derived from an inertial reference frame calculating the acceleration required to sustain circular motion or from a force balance in a rotating reference frame. You can start from first principles given either and derive the exact same equation. So you could choose to if you so desired. And again, as per the above example, sometimes considering the rotating frame makes the problem more intuitive. Neither is more correct than the other. Strict doctrine to one as being "more correct" only limits understanding of how problems can be solved.
The "Kepler force" is not really a force. It's an expression of inertia in (as I mentioned) a limited, non-inertial reference frame. It's fine to conceptualize but IMO misleading especially when explaining the fundamentals to novices.
As for the ubiquity of using a rotating frame, I'm not saying it's not done. I'm just saying it's not necessarily typical for orbits to de facto be considered in such a frame.
As for the ubiquity of using a rotating frame, I'm not saying it's not done. I'm just saying it's not necessarily typical for orbits to de facto be considered in such a frame.
Ok, but you made a comment stating that what I said is inaccurate. It's not. It's just a different philosophy for analyzing rotating systems. And importantly, it's how Karman conceptualized his dynamic model for an aerodynamic space-plane that led to the derivation of the Karman Line in the first place. Describing the Karman Line through such a rotational reference is perfectly acceptable. There's no reason at all to keep our thinking about free-body diagrams and physical models to strictly inertial frames. Doing so in no way makes a conceptual framework more accurate than any other.
I really hate this way thinking about centrifugal force and rotational frames. It's a breeding ground for pointless internet arguments like this one instigated by the most frustrating of pedantry. Spreading this idea that using centrifugal force is somehow wrong only acts to restrict understanding of physics. It also handicaps you from solving problems in ways that could be better served by changing frames.
I really hate this way thinking about centrifugal force and rotational frames. It's a breeding ground for pointless internet arguments like this one instigated by the most frustrating of pedantry. Spreading this idea that using centrifugal force is somehow wrong only acts to restrict understanding of physics. It also handicaps you from solving problems in ways that could be better served by changing frames.
It is inaccurate for any reference frame you should expect the laymen you were addressing to understand. I stand by my statement. You can invent a reference frame that will make anything "technically correct"
Edit to address your edit: And a hearty "fuck you" to you as well, you smug, pedantic arse
Edit to address your edit: And a hearty "fuck you" to you as well, you smug, pedantic arse
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> supposed to be working on some Kalman Filter models
I think we all knew that.
I think we all knew that.
another tangent: I was annoyed to hear "I can't believe I'm talking with someone from *outer* space" about a call with people on the ISS.
For me, there's nothing outer about the ISS. It's also as low as you can go, barely above the earth, tightly bound to us. But I think it turns out it's not really wrong to call this area outer space. I'm not sure, for me it would be logical to have different words for being close to the Earth (in orbit or lower) and any other place in space.
For me, there's nothing outer about the ISS. It's also as low as you can go, barely above the earth, tightly bound to us. But I think it turns out it's not really wrong to call this area outer space. I'm not sure, for me it would be logical to have different words for being close to the Earth (in orbit or lower) and any other place in space.
It's outer space because as far as a human is concerned it's outside the atmosphere, even though it's actually skirting it. If you need a space suit for EVA then it's outer space, basically.
Outer outer space could be called interplanetary, interstellar, intergalactic, etc. Not sure if there's words for the space between the Earth and the Moon (other than HEO), or above the Moon but inside the Earth's sphere of influence.
Outer outer space could be called interplanetary, interstellar, intergalactic, etc. Not sure if there's words for the space between the Earth and the Moon (other than HEO), or above the Moon but inside the Earth's sphere of influence.
Whilst its to the edge of space where weightlessness is only experienced for a few minutes, in terms of scalable processes for the masses to experience space, this seems to be one approach that could scale up quickly.
Thats a lot of words just to not mention actual altitude.
88.5139km (55 mi) according to https://twitter.com/virgingalactic/status/168967386916530585...
I would have assumed at least 100km.
I would have assumed at least 100km.
The say 55 miles here - same km.
https://www.virgingalactic.com/news/virgin-galactic-complete...
Precisely my observation. My google fu seems to be failing me as well.
What a massive waste of the limited carbon budget we have remaining as a species. The techno-optimists who think this is bootstrapping more humanity-serving missions (like a colony on Mars or the Moon) are lying to themselves. We are squeezing every last resource that makes Earth livable to enrich a few people short-term, but we will all suffer for this in the next few decades.
sigh. Ok, let me explain why this attitude is not just stupid, but evil.
It's stupid because it's simply text completion on a GPT-2 level. There's already an association between space travel and carbon, so you hear space travel and just go "yes, but global warming". No thought was put in either acquiring the association in the first place, nor in deciding if this is a good moment to use it. And definitely no fact checking.
It's a mix of stupid and evil because this kind of text completion turns the public discourse in an echo chamber of unproductive repetitions, which creates the strangest of paradoxes - like the more climate concerned somebody is, the more likely they are to be against nuclear power. This never happened because anybody made the case for nuclear being bad for climate and people actually believing this claim. There was no case and no claim in the first place - just GPT-2 style reflexes and blind associations. Space tourism bad, bio-fuel good.
And it's plain evil because it assumes that we should only dare to dream if we follow the current orthodoxy. It's not even something like "in order to dream we should make sure survival is ensured", because it was never about doing the math or actual tradeoffs. It's simply that some dreams are being painted as dirty and we shouldn't be allowed to have them, ever.
It's stupid because it's simply text completion on a GPT-2 level. There's already an association between space travel and carbon, so you hear space travel and just go "yes, but global warming". No thought was put in either acquiring the association in the first place, nor in deciding if this is a good moment to use it. And definitely no fact checking.
It's a mix of stupid and evil because this kind of text completion turns the public discourse in an echo chamber of unproductive repetitions, which creates the strangest of paradoxes - like the more climate concerned somebody is, the more likely they are to be against nuclear power. This never happened because anybody made the case for nuclear being bad for climate and people actually believing this claim. There was no case and no claim in the first place - just GPT-2 style reflexes and blind associations. Space tourism bad, bio-fuel good.
And it's plain evil because it assumes that we should only dare to dream if we follow the current orthodoxy. It's not even something like "in order to dream we should make sure survival is ensured", because it was never about doing the math or actual tradeoffs. It's simply that some dreams are being painted as dirty and we shouldn't be allowed to have them, ever.
GP is correct, there is no path from the current Virgin Galactic launches to something that is not a very expensive space ride for rich people. They can't launch satellites, they can't make it into orbit, nothing. Only the dream of seeing earth from an altitude of ~80km while expending a tremendous amount of energy.
Also, your explanation of why GP attitude is evil is not clear at all. You can dream and still thing that this is stupid. In fact, the dream of a nice earth for all of us is a beautiful dream, much more than a 5 minute ride for a very few.
And the inclusion of nuclear power when it was not mentioned in the original post is like a GPT hallucination.
Also, your explanation of why GP attitude is evil is not clear at all. You can dream and still thing that this is stupid. In fact, the dream of a nice earth for all of us is a beautiful dream, much more than a 5 minute ride for a very few.
And the inclusion of nuclear power when it was not mentioned in the original post is like a GPT hallucination.
> there is no path from the current Virgin Galactic launches to something that is not a very expensive space ride for rich people
Lack of farsightedness in this thread is weird!
Science doesn't work in a linear manner. When Ramanujan and Hardy were working on Primes, nobody knew some of the work would lead to cybersecurity applications.
We cannot be sure that these advancements don't lead to anything significant in the future.
The only focus should be on taxing the profits of this company, and also applying a high levy/VAT to the ticket price.
Lack of farsightedness in this thread is weird!
Science doesn't work in a linear manner. When Ramanujan and Hardy were working on Primes, nobody knew some of the work would lead to cybersecurity applications.
We cannot be sure that these advancements don't lead to anything significant in the future.
The only focus should be on taxing the profits of this company, and also applying a high levy/VAT to the ticket price.
>We cannot be sure that these advancements don't lead to anything significant in the future.
We also cannot be sure that this service won't cause huge damage. If we're going to assign value to it based on its unknown potential, we must consider both its possible benefits and its possible detriments.
We also cannot be sure that this service won't cause huge damage. If we're going to assign value to it based on its unknown potential, we must consider both its possible benefits and its possible detriments.
Take a look at "Crossing the Chasm" - just look for the first image google finds. In order for something to become mainstream a few steps usually need to happen. And the first of those steps are the people who will buy or invest no matter the cost. Without them, it's hard to even have an industry. Later, sometimes decades later, price manages to go down enough for mass adoption.
We're not talking about dreaming, though, we're talking about expending actual resources and dumping actual contaminants into the actual atmosphere just to, as the sibling comment puts it, give rich people space rides. Scientific space missions are at least justifiable to some extent because we might learn something useful. This is just a method for money to change hands.
> sigh. Ok, let me explain why this attitude is not just stupid, but evil.
the words of a religious lunatic.
the words of a religious lunatic.
I remember when I watched Interstellar for the first time, I thought, "No way people would be that dumb to brush off space exploration just because they're caught up with Earth stuff."
But the more time goes by, the more I think the movie nailed it.
https://www.youtube.com/watch?v=8VKTLFlwr4Y
But the more time goes by, the more I think the movie nailed it.
https://www.youtube.com/watch?v=8VKTLFlwr4Y
While we don't have hard numbers, reasonable estimates of these suborbital launches by environmentalists like [1], put them at around 10 to 20 metric tons of CO2 per passenger per launch. The average driver in the US generates about 5 metric tons CO2 per year in tailgate emissions.
Personally, I put far more value on giving people an unparalleled (and in some cases life changing) experience than a few years of commuting.
[1] https://www.treehugger.com/what-is-carbon-footprint-of-space...
Personally, I put far more value on giving people an unparalleled (and in some cases life changing) experience than a few years of commuting.
[1] https://www.treehugger.com/what-is-carbon-footprint-of-space...
> Personally, I put far more value on giving people an unparalleled (and in some cases life changing) experience than a few years of commuting.
but they will be doing both those things.
people who go to space don't stop driving cars when they get back.
but they will be doing both those things.
people who go to space don't stop driving cars when they get back.
Please tackle large carbon sources first. If small ones are still a problem then of course we should touch those as well. The Earth doesn’t care about effort or intent, only about net carbon. Touching small sources while large sources are still going is foolish, especially if it adds friction to tech development.
When's a good time to stop technology advancement for those of us who are willing to pay for it? There will never be a right time.
This is useless technology that goes nowhere except this specific use case
The best time to stop that was probably last century. The second best time is today.
The techno-optimists will tell you large scale carbon capture is Just Around The Corner. And also socially acceptable large scale geoengineering.
I share your sentiment but rocket launch is not that massive right now actually.
Very poor point. The entire point of creating a company that wants to operate in this market is to invest in it, make it more efficient and "space tourism" more accessible. It costs a kidney (or a billionaire's savings) now but surely their business plan is for more people to buy their product.
Fair. I guess my counterpoint would be it may enable off world manufacturing which may be a net benefit for the planet?
It's devastating to see comments like this downvoted. Sure, maybe the tone could be improved, could be perhaps less arrogant or judgemental, or maybe whiny. I don't know what the downvoters thought. But I hope people realize how extremely precarious of a position we're in as species. To live sustainably on this planet we all must be asking these questions, whether space travel -- or, suborbital flight tourism -- is in the budget.
> Sure, maybe the tone could be improved
Sometimes, you just have to call out the obvious. But it's been upvoted again. It seems more people have a rather dim idea of this contribution to science and humanity.
Sometimes, you just have to call out the obvious. But it's been upvoted again. It seems more people have a rather dim idea of this contribution to science and humanity.
The inspirational effect on people in general and particularly kids is not to be discounted. If you want the next generation of scientists, you have to give them something to dream about. These launches are more than worth it.
I’d encourage the kids to aim higher than a tourist trip near space.
I dunno about your career but "Suborbital spacecraft pilot" is a much cooler job title than my current one.
But there's nothing to do out there. Unless they build a casino or resort (moon seems like best target) what's the point.
OceanGate in the making. Or would that be Blue Origin?
OceanGate avoided certification. Virgin Galactic is licensed and certified by the FAA to do commercial passenger flights.
It's really the equivalent of a experimental aircraft though, the only reason they can take paying passengers is a law that restricts regulation of private spacecraft. It's about as FAA certified as a kit plane.
Blue Origin has a very safe design with proven safety systems that can trigger autonomously at any point in the flight. Basically on par with other modern crewed American spacecraft (granted, with slightly easier conditions since it doesn't have to get up to orbital velocity and back).
Virgin Galactic is definitely the closest to being a space OceanGate in the making, being deliberately manually piloted and IIRC having various points in the flight profile where it's essentially a guaranteed loss of crew if the pilots make any mistake.
Virgin Galactic is definitely the closest to being a space OceanGate in the making, being deliberately manually piloted and IIRC having various points in the flight profile where it's essentially a guaranteed loss of crew if the pilots make any mistake.
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Not really. Space is a really chill environment. The worst that could happen is your spaceship blows up, but we’ve gotten pretty good at not doing that lately. The bottom of the sea is far harsher and less forgiving. Everything about it tells you you’re not supposed to be there.
It's a fair question because Virgin Galactic had played pretty fast and loose with safety in the past. It was only a matter of time before they killed someone. https://en.wikipedia.org/wiki/VSS_Enterprise_crash
Fortunately, they don't seem to have had a major incident since 2014 and the FAA has certified them for commercial flights.
Fortunately, they don't seem to have had a major incident since 2014 and the FAA has certified them for commercial flights.
> It's a fair question because Virgin Galactic had played pretty fast and loose with safety in the past.
This is a tangent, but I was thinking that we got a bit lucky with the first Starship orbital flight test.[0] When you look back, chunks of fondag could have easily taken out specific Raptors which would have led to a trajectory towards a city. Now we know that Booster 7's flight termination system was basically non-functional.
SpaceX has a pretty great reputation with safety, nothing like Virgin, but that Starship test seemed far from safe.
[0] https://en.wikipedia.org/wiki/SpaceX_Starship_Integrated_Fli...
This is a tangent, but I was thinking that we got a bit lucky with the first Starship orbital flight test.[0] When you look back, chunks of fondag could have easily taken out specific Raptors which would have led to a trajectory towards a city. Now we know that Booster 7's flight termination system was basically non-functional.
SpaceX has a pretty great reputation with safety, nothing like Virgin, but that Starship test seemed far from safe.
[0] https://en.wikipedia.org/wiki/SpaceX_Starship_Integrated_Fli...
Kind of an overestimation.
From the launch site to actually have a trajectory that hits the inhabited part of the island isn't that easy. One Raptor getting hit wouldn't be enough. The whole central steerable core of engines being knocked out, and not only that, in a way that shifts the trajectory in the exact 'right' place is incredibly unlikely. Specially as the rocket would likely also try differential steering.
The flight termination system might very well have worked just fine in most circumstances. By the time it was triggered the rocket was in strange position and already flipping. We don't have official information yet but it seems likely that had something to do with it.
For anything bad to happen a huge number of very low-probability events would have to combine to lead to that outcome.
From the launch site to actually have a trajectory that hits the inhabited part of the island isn't that easy. One Raptor getting hit wouldn't be enough. The whole central steerable core of engines being knocked out, and not only that, in a way that shifts the trajectory in the exact 'right' place is incredibly unlikely. Specially as the rocket would likely also try differential steering.
The flight termination system might very well have worked just fine in most circumstances. By the time it was triggered the rocket was in strange position and already flipping. We don't have official information yet but it seems likely that had something to do with it.
For anything bad to happen a huge number of very low-probability events would have to combine to lead to that outcome.
I wonder what's the commercial price point. I wish it could be as low as 30k USD in 10 years so maybe I can do that too.
Virgin Galactic prices will likely never go down. They had to spend far more money than expected to scale up from SS1 to passenger flights. They have around 600 reservations at $200K, and it is questionable whether they can break even providing flights at those prices. They won't begin to make profit and be able to earn back their upfront investments until they complete those reservations, and start flying new customers for whom the price is now $450K.
Blue Origin's approach is more scalable, but they won't talk price at all which suggests they are charging just as much if not more - likely whatever the market will bear. It will be a long time before they've flown all the customers who are willing and able to pay current prices, so there is no profit incentive to decrease prices.
NASA has contracted SpaceX Dragon flights at about $70M per seat, and the OIG estimates the cost to SpaceX at $55M per seat. If we are extremely optimistic about Starship and say it will cost the same amount to launch as Falcon 9 / Dragon, and has 100 passengers instead of 4, that brings the price down to $2-3M per seat, so still way more than Virgin Galactic, although you get more as well (Inspiration 4 was LEO for 3 days, instead of freefall for 3 minutes).
The only way I could see the prices going down significantly is if you had something like Starship alone (without super heavy booster) doing frequent sub-orbital hops (like daily). I won't venture a price WAG for that though.
Blue Origin's approach is more scalable, but they won't talk price at all which suggests they are charging just as much if not more - likely whatever the market will bear. It will be a long time before they've flown all the customers who are willing and able to pay current prices, so there is no profit incentive to decrease prices.
NASA has contracted SpaceX Dragon flights at about $70M per seat, and the OIG estimates the cost to SpaceX at $55M per seat. If we are extremely optimistic about Starship and say it will cost the same amount to launch as Falcon 9 / Dragon, and has 100 passengers instead of 4, that brings the price down to $2-3M per seat, so still way more than Virgin Galactic, although you get more as well (Inspiration 4 was LEO for 3 days, instead of freefall for 3 minutes).
The only way I could see the prices going down significantly is if you had something like Starship alone (without super heavy booster) doing frequent sub-orbital hops (like daily). I won't venture a price WAG for that though.
Plus the insurance on virgin galactic flights is probably pretty expensive too, assuming they can get it at all. It's a deliberately dangerous design, needlessly putting passenger lives at stake for the sake of claiming to be human piloted.
At least Blue's vehicle has shown itself to be pretty safe for passengers.
At least Blue's vehicle has shown itself to be pretty safe for passengers.
> can break even
... they can't.
> they complete those reservations
... they wont.
... they can't.
> they complete those reservations
... they wont.
A suborbital flight is not exactly 'going to space' in any meaningful terms.
If lack of air qualifies as going to space, then the economy flight I was on last week got me four-fifths of the way to space.
Neither it, nor VG is anywhere close to capable of taking me into orbit, though.
If lack of air qualifies as going to space, then the economy flight I was on last week got me four-fifths of the way to space.
Neither it, nor VG is anywhere close to capable of taking me into orbit, though.
'Space'.
The claimed maximum altitude on previous flights was 87.2 km.
There are arguments for and against calling that "space", especially since the vehicle isn't designed for orbit. Either way it's an achievement, and I don't see value in belittling it. Why not express excitement for one day going higher?
There are arguments for and against calling that "space", especially since the vehicle isn't designed for orbit. Either way it's an achievement, and I don't see value in belittling it. Why not express excitement for one day going higher?
Because it is a definition. Just like a kilogram or a meter.
Only someone who does not understand what the Karman Line is and is not would claim that there is "a definition for space" like kg or m.
If you are now going to resort to "the FAI's definition", by the FAI's standards Yuri Gagarin did not fly the first orbital flight because he ejected from Soyuz I near the end, something the USSR kept secret so it could claim the achievement.
If you are now going to resort to "the FAI's definition", by the FAI's standards Yuri Gagarin did not fly the first orbital flight because he ejected from Soyuz I near the end, something the USSR kept secret so it could claim the achievement.
define it.
Because I feel like it's an entirely pointless waste of resource? I don't know if you've noticed, but the world's on fire right now.
Moreso though, if you're not achieving orbit, you're not really visiting space proper, imho.
Moreso though, if you're not achieving orbit, you're not really visiting space proper, imho.
Can you explain why orbit is such an important point to you? If I got launched to 1000 miles out and just “fell” back to earth without achieving orbit I’d definitely consider it a trip into space.
Smells like sour grapes. Turn off the news it’s not good for you
Smells like sour grapes. Turn off the news it’s not good for you
It's not important to me at all. It's a pointless ambition. I'm just sorry that it's seemingly important to other people. shrug
The final frontier?
Space is the final frontier, not the last frontier, because we must make giant steps in biology to become a spacefaring species.