Boeing: “[We have] restructured our leadership team to better align with current program challenges, and we are refining our approaches and tools to ensure a successful transition from development to production.”
Sounds to me like utterly worthless corp-speak for "shit isn't going so hot, but we are going to fix everything, just you wait". I think there might be trouble in paradise among Boeing's top brass.
In no way surprised to hear this, especially after seeing Boeing spreading FUD here recently (https://news.ycombinator.com/item?id=18139146). They must not be comfortable with all of the other upstarts in the industry threatening their comfy spot as one of NASA's go-to contractors.
It seems weird that the Falcon 9 only includes numbers for "v1.2"(I'm assuming this is block 4/5?), while other vehicles don't have the same granularity. Also IMO it should count as a failure to blow up on the pad and destroy your payload, even if it's before the launch.
Perhaps you mean world's most reliable currently active launch vehicle? At your link, I see the retired Atlas 2/2AS also had a perfect record, with more attempts (63 successes of 63 attempts).
I don't get it. NASA should re-vector as an overseeing space administration for US based space projects, and let the commercial sector do the actual building, testing, and flying. Think of all that money saved that can be used for a better purpose elsewhere.
That is currently how things work, and if you were to topple the current system and try to do the exact same thing over again you will get the same result in a couple of decades: a few entrenched aerospace firms with deep connections to congress on corporate welfare and eye-popping flight cycle costs.
There is billions of spending on projects they don't need, forced by congress, like SLS. It's mostly not independent systems - space x is far more separate than boeing and other companies.
"There is billions of spending on projects they don't need"
On the list of governemnt expenses... NASA is almost a rounding error ($18.4 billion in 2011, about 0.5% of the $3.4 trillion US budget). Perspective is important.
I think their point may have been (and if it wasn't, mine is) not to cut that funding but to reallocate it to more oversight so the overall pace of space production and research can be expanded.
Yes my point is not that nasa is a bad thing - I want to increase spending at nasa. But I don't want it to be wasted on basically congressional district earmarks. There's always been some of that going on, unfortunately, but the SLS is a major drain on other things at Nasa. They can't afford to waste money on this. SLS may never fly, it's at least a big rocket looking for a use case.
I think the point is they shouldn't pay for the R&D or the construction of the rockets either - just pay for the launches and let the market sort out what vehicles are required.
The SLS is not about space. It's been referred to as the Senate Launch System for years now and that's very accurate. It started back in 2010 and still isn't going up anytime soon. For comparison the first time we sent anything into orbit (a probe) was 1958. The first time we put a man in orbit was 1961. In 1962 Kennedy would give his famous space speech. In 1968 we sent a man around the moon. In 1969 we put a man on the moon. Compare the timelines and it's simply pathetic.
But what the SLS does provide is an immense number of jobs, votes, and support for the congressmen that keep it funded.
The last chief of NASA, Charles Bolden, was the person you want on paper. A decorated and high ranking military officer who was an astronaut with a STEM education. What he was not was a political player, and I think NASA has suffered under him. The person that has replaced him is, at a glance, is the exact opposite of who you want. Jim Bridenstine is an MBA, career politician, and has no technical background whatsoever. But he does have a genuine interest in space which he has worked to support for years, and he is, for better or for worse, a political player.
And I have hopes and expectations that he will change the direction of NASA into the far more logical direction that you, and just about everybody, sees would be more productive. And I think we're already seeing this. Recently NASA released a scathing report against the SLS which said, without mincing many words, that they're not going anywhere anytime soon if they have to rely on the SLS. The lengthy report is here [1], here [2] is a random media report on it to give some sort of cliff notes. This is the sort of stuff that Bolden, for whatever reason, did not have the capability or will to push through. That report didn't say anything that everybody didn't already know, but actually stating those things was speaking what must not be spoken - and is now something that demands action.
While I agree with you about NASA funding pork projects these days, there is another side. I don't think people realize how important pork might be (I'm speculating this isn't a firm belief for me). Without pork projects, we could have even more wealth disparity in the US. What would happen to Alabama if the NASA funded aerospace programs went away? What would happen to the low cost of living areas dominated by retired persons is social security payments went away?
I believe this is why the EU has had problems - they're all on the same currency but countries are not permitted to print their own money and they don't have international money redistribution programs. In such an environment any country with a trade deficit will eventually suffer - see Greece.
I'm not advocating such pork distributions but I think they may actually serve a purpose other than getting votes. OTOH some places get pork that really don't need it even for the reasons I outlined above.
Yanis Varoufakis, the Greek minister of finance during the height of the Greek debt crisis, believes that this type of redistribution (defense spending is a much larger amount) in the USA has allowed it to exist with a common currency without having the same level of problems that Europe has. There is no mechanism in Europe to move enough money to the poorer parts from the productive powerhouse, Germany. This is causing very large problems and a lot of people suffering in southern Europe. French and German banks got a bail out like US banks in 2008 to prevent an economic collapse, but the debts were not forgiven (more money was borrowed to pay the loans) and this problem come back again at some point.
> There is no mechanism in Europe to move enough money to the poorer parts from the productive powerhouse, Germany.
There are several mechanisms to move money [0], just the free movement of labor alone has transferred a lot of money from Germany further to eastern Europe for decades already.
I fail to see how military exports would be better than that, defense products are not "money", they serve no productive purpose at all in any country that's not at war.
It should also be noted that Germany is among the biggest weapons exporters on this planet [1] and quite a big chunk of Greece debt boiled down to liabilities for military hardware from other EU members [2].
I don't think you quite understand what I was saying. Free trade is the problem, not the solution. Germany makes a lot of stuff and sells it to the southern countries, running huge trade surplus. The southern countries borrow to buy the stuff and eventually have debt problems. There is no mechanism to get money from Germany back to southern Europe in the amounts needed. Before monetary union, Italy or Greece would see their currencies go down and the trade deficit would start to balance out.
In the US the people in rich parts of the country pay more in taxes to the federal government than they get back. This is a good thing, not a problem like many people state. It is not about building weapons for export, it is that the US government spends $600 billion on defense spending, moving resources from rich parts of the country to the poorer parts (to pay for government bases and defense contractors that build weapons for the US government). I agree that there are better ways to do this redistribution of wealth, but it is the only one that seems acceptable to the Republican party. Building infrastructure could be another, but it has not happened since the building of the interstate system ended in the 1980's.
The EU supra-national government (very similar to the US federal government over the US states) has a very small budget (€143 billion for the year 2014, from Wikipedia) and no real ability to raise large amounts of money from taxes it can impose. Varoufakis believes that until the EU has such a mechanism, having a common currency is going to continue to build up financial problems that are like to break up the union in a bad way.
What I would wonder is how long of a staying power does this kind of relief have?
If I build a missile factory in Baghdad, Mississippi that runs for 20 years then is closed won't the same problem persist as before the missile factory was created?
I think your point that free trade is the problem is fairly evident in this kind of problem, however, I am not sure that spending on things such as military producers or even national infrastructure is a long-term solution. In the end the project always ends, the product stops being produced, and times change.
Is this just delaying the eventual wealth-death of a town/state or does this lead to a self-sufficient system?
I should have stated the EU is like the early US and that it will probably have to grow federal power to succeed. Similar to how the US states found its articles of confederation did not give the federal government enough power to solve the problems it was expected to solve and 12 years later they were with the current US Constitution.
That's true. Pre-BREXIT I was no tagainst the EU, I simply thought that it was a tad too intrusive at times. So, yeah, I understood some of the reasons why the Brits wanted to leave.
Then, either the EU changed or I did or both, and my opinion changed. Trump definitely did his part to wake me up and see that BREXIT was less about the EU itself as I initially thought and more about populism and protectionism. Both are things I never liked. I still hope that BREXIT served as a overdue wake-up call for Brussels.
Now, I favor European integration and cooperation. I'm simply not sure where to draw the line yet. Defense politics and military cooperation are definetly over due and the EURO needs some kind of reform (no idea how exactly, but the last crisis showed the current system to be not stable enough).
Would I support a "United States of Europe"? Good question, maybe it's inevitable one day. The issue definetly will be that European nation states are much more different, culture, language, politics, history, than American states which share a common history starting with the first settlers. I for my part see the risk of loosing something.
Now that I think about it, that could be a reason for the rise of populist movements.
Now imagine if we paid those people to do something productive instead of wasting so much time. Heck what if we just gave them the money and let them work on whatever they wanted. It would still have a better payoff.
The illusion of contributing value needs to be maintained or people will get angry at the freeloaders getting paid to do nothing. People building the US military machine are not doing nothing just because the output has no real value.
”The European Regional Development Fund (ERDF) is a fund allocated by the European Union. Its purpose is to transfer money from richer regions (not countries), and invest it in the infrastructure and services of underdeveloped regions”
NASA's job comes from NACA's: to be at the bleeding edge of aerospace research and actually do the things that aren't economical for the corporate world yet.
This seems to be a dig, but it has no content. I mean, sure, if the funding was greater, the speed of research would quicken in many cases. But you can't criticize from both directions. Do you want cheaper, or faster?
Also, "bureaucratically neutered" is an odd phrase. It's the government, so of course there is oversight and politics at an agency level. But OTOH, the agency's record at not interfering with discrete science findings is actually very good.
What point are you trying to make? [Disclosure, I have published research while funded by NASA.]
I can't say I understand how that's criticizing from both directions. The research is underfunded, and as you noted more funds generally increases the speed of the research. There are layers of bureaucracy, which naturally slows down the rate of research due to waiting on various aspects of the research to get reviewed and deemed useful to the agency. How is that attacking it from two sides?
And your take on what I mean by "bureaucratically neutered" is fairly accurate, but I stand by it. I am referring to having non technical bureaucrats in the agency calling shots about research they may not understand based on non-related pressures (pork funds drying up due to political shifts, undesirable media exposure for research with uncomfortable results, sudden change in leadership that may not think the research is necessary after all, etc).
All this said, I have indeed never been involved with the agency so you might have a better perspective on the matter than I.
In my experience your comment has very little grounding. I have an extensive science publication record from research supported by NASA. Aerospace and aerospace technology (as opposed to science) is more sensitive to top-level agency strategy changes.
A fair distinction I failed to make, and a point well taken. To also be fair though, I think generally when the layperson (me included) considers NASA and things under its purview, it's easy to blindly scope it within the context of aerospace, especially beside the context of this particular article.
Also, I'd think at JPL you guys would have a bit easier time getting funding/latitude to do the research you do vs a lower profile lab, given JPL's track record.
Does it really? Bureaucracy can very well be counterproductive to such contingencies. The problem that caused the Challenger disaster actually did get documented and reported, but the issue still got lost in the layers and layers of red tape needed to get a shuttle off the ground. Hindsight is 20/20. There is no guarantee that adding more oversight would have avoided the accident.
I have neither the time nor the inclination to explain myself to a man who rises and sleeps under the blanket of the very science that I provide, and then questions the manner in which I provide it! I would rather you just said "thank you" and went on your way, Otherwise, I suggest you pick up a gyroscope and stand an experiment. Either way, I don't give a damn what you think you are entitled to!
That page does not contain any mention of the microwave oven. The use of microwaves for heating food was patented in 1945 and first commercialized in 1947, well before NASA:
I don't think the microwave applies here. Folks were nuking food with radio waves as far back as the 30's, long before NASA was even close to being around.
> The purpose of defense contracting is to dish out pork to congressional districts.
Edited to reflect my opinion of reality...
If you look at how the individual subsystems and subcontractors for the F-35 program were spread around various states and congressional districts, creating jobs in various places, they intentionally designed it to be unkillable.
This is one of the nasty legacies of the Apollo program. NASA crewed spaceflight has always been a lot messier, a lot more political, and a lot more pork-barrel oriented than robotic spaceflight. That goes back to the Johnson administration and the extensive politicking he did to make Apollo happen. He very cleverly figured out how to locate NASA centers and contractor jobs to areas with a lot of political power in congress. However, that legacy has outlasted the Apollo program and today we have the SLS, which has the primary purpose of funneling government money to several very specific corporations in very specific congressional districts. Results are, at best, a secondary objective.
JWST is just one program among many. Also, it may seem that it matches the level of problems of crewed spaceflight but it really doesn't. The JWST program's enormous budget is small (in per year amounts) compared to things like Orion or SLS. If JWST was burning through money the same way SLS was it would be a $40-50 billion program.
Additionally, there is a huge number of highly successful robotic missions that have been running or are in the works. Just now in terms of active programs there is the Curiosity rover, the Juno Jupiter orbiter, the Parker Solar Probe, New Horizons, InSight, Dawn, TESS, Osiris-REX, MRO, Fermi, STEREO, and many more.
The big danger for the SLS will be when SpaceX's BFR starts flying. Not only will both stages be reusable, but for flights beyond the Earth a BFR will first go into orbit, and next be refueled there by another BRF, and then take off with full tanks, instead of the almost empty ones as will be the case with SLS.
The result is the BFR will be able to land 10+ times as much cargo on the Moon or Mars as the SLS, and at maybe 1 percent the cost per ton.
I think what is going to happen is the tax payers will finally wake up to how they are being ripped off, and the SLS program will be canceled.
It was all over the news yesterday. It didn't get buried.
More likely, today's event provides some positive increase to the political argument in favor of plowing billions more into getting all the new US launch systems up to where they need to be.
Most people reading the news won't understand these valid points you are making. To them, any US-made rocket is sufficient for "doing necessary space stuff that the government tells me they need to do."
Technically, it is not needed to ensure that NASA is funded. Congress and the current administration think it is needed, because they're stuck in the 1960s and think the space race is still a thing (meanwhile ignoring/underfunding crucial planetary and Earth climate sciences that NASA also performs).
It was sarcasm. The jobs in key congressional districts would disappear if NASA was allowed to do what makes sense for an effective space exploration program. So congress has taken over mandating what NASA's goals should be, to make sure that their key constituents remain employed on government contracts.
It seems like no one is hold Boeing accountable for completing the project with the given budget. And to add insult to injury, Boeing is being improperly awarded tens of millions of dollars for performance fees the company has not earned [1]. If a project is failing, just cut your loses and scrap it. This political pork spending doesn't help anyone excited about space exploration.
What guarantees do tax payers have that the money won't be wasted at SpaceX just as it's wasted at Boeing?
Why not scrap it, and just save the money. Full stop.
If Boeing and SpaceX are not able to do their things without NASA continuously pumping new billions into them, then we should take a step back, reevaluate, and consider a total rehaul of the future roadmap. Because obviously things aren't working.
But we're not at that point yet. The only thing we've proven thus far is that giving out lots and lots of money does not seem to solve the problem of project setbacks.
NASA has little say in the matter, this is a congressionally mandated project. NASA didn't want it, but it turns out to funnel money into mostly the same companies that were getting money for the Shuttle program, and congress loved that so now NASA has to make do with what they are given.
9B is nothing when you look at how much waste is spent in the military, like the the Abrams tanks that the military consistently says it doesnt want but always gets [1] [2]
They don't want to preserve Abrams building capacity. The Army not only has enough for current needs, they already have enough for every possible contingency, including: "WW3, except for some reason it's not fought with nukes but with gigantic tank battles."
Assuming the Army rotates tanks out of front line service before they are useless, by the time the fleet is too worn out, the Abrams design will be hopelessly obsolete. Not because the design is bad or obsolete, but just because that's how many of them there are.
In contrast, the Army has massive deficiencies with many of their other, lighter vehicles, and has been trying to rectify them for decades now but all the projects have failed, for various reasons. Some of the failures have been the Army's fault, but others can be traced to the Congress deciding that the Army needs more tanks to stockpile instead of, say, armored ambulances.
Honestly, what the army really needs to do is somehow push for a heavy IFV/APC design based on the Abrams chassis, similar to how the Russians have made the T-15. Not because that would be a great match for their needs, but because since the production line is apparently completely impossible to kill, might as well try to have them make something that is even marginally useful, compared to the vehicles they are building right now that just get driven from the factory to permanent stockpile where they will probably sit until they are decommissioned decades in the future.
I meant the Shuttle, but not so much in a "it was a terrible design" and more along the lines of "it had its design pulled in a bunch of different directions and ended up being less efficient at any of the tasks" which is what I feel the core of the original video.
The Russian Buran(?) was pretty clearly a better system and if I understand right thats because it wasn't trying to be the catch all system with competing goals from the Air Force, internal NASA goals, and congress/the senate(? not American so not sure which is correct here).
How would you reconcile this claim that Buran was a better system when Buran was stolen Shuttle technology and wasn't reusable? See http://blogs.discovermagazine.com/crux/2016/12/14/buran-shut... among other places for more on NBC's reporting on the theft.
And the US rocket program was "stolen" German technology - even including the scientists and engineers. And Germany "stole" a lot of technology from Britain during the industrial revolution. And somebody "stole" silkworms from China a long time ago. And the recipe for gunpowder. And for porcelain. Writing was invented in only a few places - I bet nobody of those using it where it wasn't invented paid the actual inventors a dime (or whatever the currency was then and there, probably wheat). Everybody "stealing" from everybody.
Oh please. Maybe information should just be shared, especially with those worse off where "you have to pay for it" would not even work, and maybe that "debt" concept is stupid to begin with (you cannot pay - you will be in eternal debt because first you have to pay me back, for more and more stuff, than interest). Maybe humans should just be more open and kind towards one another to begin with, especially when it does not even "cost" them (the counter argument "but they will compete with us" just means that you have to suppress them, because in any scenario where they do get to rise eventually they will compete with you anyway, especially when we are talking about a billion Chinese and the other couple of billions of people in Asia).
The reason for IP controls is, and has always been, suppression, because technology is a way you get money and power. It's sad that humans have been doing their best to suppress progress that could benefit everyone just so that they could hold on to their share of the pie.
The orbiter was reusable. As for Energia rocket, it burned up but in reality, Space Shuttle's SRB weren't reusable either (it was much cheaper to make new ones than to recover and refurbish spent boosters), and Energia could at least serve as an independent lifter without Buran.
The Russians may have stolen Space Shuttle design (though no one really cares), but they have definitely improved on it.
Eh, not really. It's an impressive piece of technology, but in the end it failed to realize the goal of low cost access to space through reusability. It made so many sacrifices to get reusability and the crossrange the air force wanted that it had many single points of failure and very limited abort options. This in turn required a very high degree of confidence that components would function as intended, which drove refurbishment costs through the roof.
Though you are not wrong in details, reality is a bit more complicated than that. The STS (shuttle) was pretty well engineered for the politically-driven requirements it had, and if not for the stupid don't-upgrade-human-rated-design mentality of space operations at NASA post-Challenger, it could have been iterated towards a cost effective solution (e.g. $150M per launch, 90's money). There were plans in place for this--flyback boosters instead of ocean recovery with impact and salt water damage; cross-fed H2/LOX boosters instead of explosion-prone SRBs; insulation-less external tank design; non-crewed variants with more payload to orbit; v2 of the main engine that would have required less refurbishment; etc. They just all got scrapped. Shuttle got expensive because of a bunch of unforeseen stuff that could have been fixed but they decided to work around instead.
For a look at the design itself and how remarkably shuttle achieved its goals, I'd suggest the MIT engineering course that covered it[0]. Also look at Shuttle-C[1] or Magnum[2] for an idea of how things could have gone.
Good design how? The Shuttle had a mess of disparate, conflicting requirements that meant it fulfilled none of them well: huge cross-range capability for the sake of an Air Force "capture a satellite in less than 1 orbit" mission that never actually happened (which compromised the design aerodynamics), heavy-lift cargo capability (which meant the SRBs with inherent safety problems), human-only operated (which made it expensive for cargo), reusability that ended up being more expensive than a disposable vehicle...
Depot maintenance. It’s a near full teardown and rebuilding of the platform. How do you think B-52s have been sustained over the past 65 or so years? Long enough that we may have four generations of pilots in one family (I’ve met several B-52 pilots who had a father or grandfather who flew the same airframe).
I don’t follow the logic. The vehicles do totally different things. We built enough F-22s and stopped. We built more Abrams than we need and continue to do so. The relative price has nothing to do with the need. Money we spend on building Abrams is wasted and could be spent elsewhere with better effect but not on F-22s which we have enough of.
Why wouldn't you want an Abrams? It does all the things. Sure, it's pigfat, but it's a proven design and it's not hard to stick an APS on it. Honestly, the Abrams is kind of like the A-10 and the F-22, even if you are trying to make fun of the US military, there is just nothing to latch on to with those platforms. They do what they are supposed to do, even when taking cost into consideration.
Edit: I admit to not reading the article and not knowing about the over-production.
It’s like chocolate cake. Chocolate cake is great! It’s simple, it does what you want. There’s nothing wrong with chocolate cake.
But you’ve already got 250 chocolate cakes. Want another fifty chocolate cakes? No? Why not!? There’s nothing wrong with chocolate cake!!!
You want bicycles and books? Pffft. You get chocolate cake! Congress has just ordered another 50 cakes for you this week, with a bill for 300 in the pipeline.
What is wrong? Why are you complaining!? You don’t like chocolate cake!? There’s nothing wrong with chocolate cake!
I guess you could read the links to find the answers to your question. But here it is anyway
> "we don't need the tanks. Our tank fleet is two and a half years old on average now. We're in good shape and these are additional tanks that we don't need."
My whole point was spending 9B on a rocketship is nothing compare to what we waste (not all military spending is waste, but there is plenty of waste in the defense budget) that we can afford to buy this rocket from Boeing. We probably spending more on healthcare for retired politicians than space exploration
The US Government spends almost twice as much on the kidney failure program (the End Stage Renal Disease (ESRD) program), $32.8 billion[1] than on NASA $19.5 billion. Very hard to find the ESRD figure, if you don't already know what it is called. NASA budget is very easy to find.
If you're suggesting that we stop paying for this, I agree in principle, but I'm afraid it would cause some bad incentives. It's hard enough to get them to retire already.
> Why wouldn't you want an Abrams? It does all the things
Because you haven't fought the kind of war that heavy armor is useful (particularly on an effectiveness to logistical burden analysis) for in decades, and don't expect to in the foreseeable future.
Abrams lit up Iraqi T-72s recently. Absolute air superiority isn't a thing in a real war, even for the US. ATGMs will lose their deterrence factor if APS systems end up working as advertised, so tanks will regain their relevance.
Also, tanks support infantry in cities. When properly utilized, they don't end up on fire like T-80s in Grozny. Again, during the Iraq war, marines were supported by tanks in cities.
None of which means squat when you consider that you could wipe out half of all the US Abrams in the world and we'd still have too many to use for any foreseeable conflict. You're arguing that the Abrams is a good platform when nobody is saying the opposite. It's a great platform.
But we have plenty of them, and we don't need to build anymore.
Respond to the point people are making and not the point you have a response for.
Yes, let's have some perspective, starting with you. The perspective is not some "waste on military" like so many in this thread claim, the actual relevant comparison is what the $9 billion could have done invested in other rocket companies. You've set up a "big entrenched corp player only or else nothing" dichotomy that was possibly relevant for the 1960s-2000s. But it was obsolete at least as of 2010 with the successful launch of the Falcon 9. If we're talking billions for relatively blue sky research, there are now more players, and players with far more proven capability to deliver and far, far superior designs and ambitions. The SLS even if realized as planned is garbage at this point, to have a sustained lunar presence requires far better economics then it could ever offer. It's not the 60s anymore, and NASA's (and the US government overall) own stated goals the point is not merely to get people back on the moon for a bit then leave but rather to develop something more permanent and useful. A fully reusable methalox stack is just a fundamentally better goal there.
Should NASA continue to support R&D? Absolutely! And I'd fully support putting even more billions into that. But just because it's a "rounding error" to the US budget doesn't make billions "pocket change", it's still completely reasonable to expect value for the money. The same is true anywhere else, just because some people are spending more and have higher budgets doesn't mean they want to piss that budget away. I'd love to see NASA pouring billions into the BFR and Blue Origin's efforts or even more blue sky stuff like going back to some older experiments with a modern twist and working on methalox linear aerospike engines, and then making all that available to US businesses. NASA doing both science and also risky but potentially big payoff basic rocket R&D would be awesome and valuable, and well worth billions. NASA flushing billions down the Boeing drain is not equivalent, in fact what makes it so enraging is precisely that it could be working towards space exploration and development so much more effectively (still providing American jobs even!).
So pretty much every government expense, no matter how shitty or worthless, is "pocket change" and can be ignored, as long as it's at least an order of magnitude less that the cost of the F-35?
Do you use the same reasoning in your personal life as well? Buying worthless stuff as long as they cost less than 1% of the cost of your house?
Sounds to me like utterly worthless corp-speak for "shit isn't going so hot, but we are going to fix everything, just you wait". I think there might be trouble in paradise among Boeing's top brass.
In no way surprised to hear this, especially after seeing Boeing spreading FUD here recently (https://news.ycombinator.com/item?id=18139146). They must not be comfortable with all of the other upstarts in the industry threatening their comfy spot as one of NASA's go-to contractors.