I Am Stewart Weinstein. I am a NASA Engineer who worked on various projects such as the Hubble Space Telescope. AMA!

What is your personal favourite picture that the Hubble Telescope has produced?

The Crab Nebula

Was your work on the optical side of things, or mechanical? Was the Hubble work done in CodeV or Zemax or something else? With modern ceramics and technological developments what changes do you think would be made if Hubble was made today?

A combination of mechanical and electrical. My biggest contribution to the Hubble was that I worked on replacing the failed gyroscopes in the Hubble.

Cool. Can you briefly discuss some of the materials concerns that you have to consider when fabricating electromechanical structures for spaceflight? Were they Invar or something else? Are the motors radiation hardened?

One of our concerns is that we have to use something strong and light. The Hubble used a lot of Beryllium, which is fantastic for space travel.

Can you make a Death Star for us? So we can blow up lesser planets?

What do you think Area 51 is for?

What is the work environment like at NASA? What was your workspace like? Was there anything really cool you got to experience as an employee?

Very creative. Lots of brilliant all in one space results in amazing things. My workspace? Suffice it to say that I am not a neat person. Papers everywhere. The coolest thing I got to experience was probably being able to meet several astronauts.

I hope you meant to say "several" and not "severed"...

That's embarrassing... yes I meant several.

Which astronauts did you meet?

All of the ones that worked on servicing mission 3A as well as others at more casual events.

If the warp drive experiment is successful, how long will it take to build? Is it something we may see in our lifetime?

I suspect we won't see it in our lifetime, but that's just me. Some say we will, some say we won't.

your thoughts on the private sector picking up the responsibility of space exploration? Outside of bureaucracy inside NASA holding it back (funding, permissions etc. will this help us on our journey of moving forward or hurt it? Is there a place for government in space exploration outside of funding?

I think that the private sector taking over space exploration is a good thing. Because it makes it more economical to explore space, which, as I mentioned, is vital for our species. It also helps to support private industry and provides jobs. Government absolutely belongs in space exploration. The list of things that could/should be explored is nearly endless, and government is a good tool to get us there.

Can light pollution from cities on Earth affect devices in space?

Have you been to space?

Absolutely, the telescope is always pointed away from the earth because the light from the earth is so intense that it would damage the optics in the telescope. The Hubble is equipped with a lens cap that closes when too much stray light enters the telescope.

how much do you make a month(money)

I made around $100,000 dollars a year, but I do not work with them anymore.

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Because it gives us better knowledge of how our solar system was formed and where other living things in the Universe my reside. Looking at the stars gives us invaluable insight into our surroundings and ourselves. Insight that cannot be found on Planet Earth.

Being a man of science for so many years, do you consider yourself an atheist? Also, do you know the general religious demographics of NASA?

That's a tough question. Yes, I would consider myself an atheist. There is a very large percentage of NASA. That said, I do not dislike religion. There is a purpose to it, and one that I think is important.

Would you rather fly to the moon with a horse sized duck, or 100 duck sized horses?

Definitely the horse sized duck.

What's your education like, and what's an average day like on the job?

My education was extremely demanding. As an example, where most people go for 4 years to get a degree to get a Bachelors degree, I had to go for 5. Additionally, I went to another University for 4 years to get a Masters degree.

A traditional day was very intense. There was an enormous amount of meetings with other sections of NASA. Several all-nighters were pulled.

where most people go for 4 years to get a degree to get a Bachelors degree, I had to go for 5.

What was your major?

Aerospace Engineering.

How much did the hubble telescope cost?

Most estimations today say around $10 Billion Dollars US. I think that it's a little lower, maybe around $7 billion. The cost was originally predicted to be around $500 million dollars. The sole cost of building it was around $2.5 billion.

It was my understanding that a big portion of that cost was essentially NASA getting "fleeced" by the contracted company that ground the primary mirror (and to add insult to injury even after all the cost and time overruns it was ground incorrectly, leading to the need for the first repair mission). How much did the mirror issues affect the final cost of the HST?

Yeah, this is true. It probably doubled the cost (of the original mission) because we basically had to do it twice.

How is required aperture decided or computed when designing a new space telescope system? Aberrations don't scale linearly, so it has to be a first-principles approach? Or is it a scaling/re-optimization of the optical prescription?

It depends on what is being observed, and the intensity of light light source that is going to be detected. It's a re-optimization of the optical prescription. Great question!

When you look up at the sky, do you feel a sense of wonder and amazement? I didn't feel this way as a kid, but now that I am nearing 30, I can't stop feeling like an excited child when I look up at the stars.

Absolutely. That drive has kept me going throughout my long career.

Can you give a little bit of rundown on your involvement with Hubble? Were you in it from the beginning? At Danbury? A launch engineer? Maintenance? I'd like to ask a lot more questions but I don't know enough about you!

Perhaps I should have explained this in the body of my post. I apologize. I led teams that led to the eventual design of replacement gyroscopes for the Hubble. The gyroscopes are part of Hubble's pointing system. They provide a frame of reference for Hubble to determine where it is pointing and how that pointing changes as the telescope moves across the sky. They report any small movements of the spacecraft to Hubble's pointing and Control System computers. The computers then command the spinning reaction wheels to keep the spacecraft stable or moving at the desired rate. The gyroscopes work by comparing Hubble's motion relative to the axes of the spinning masses inside the gyroscopes. In the absence of external torques, these axes remain stable relative to the fixed stars in the sky. By keeping Hubble fixed relative to these axes, Hubble stays stable relative to the stars.

The Hubble could not function until the replacement gyros were implemented.

Thank you for your answers, this AMA is really cool for a junior engineer like myself. What is the power requirement on one of those gyros? Were they constantly in operation, or only when a correction was needed? If they were constantly going, how on earth did you guys avoid abrasion at the axles?

A lot of good questions. The power needs to be an is relatively low. The power that a gyroscope uses to run is around the equivalent that your household lightbulb would use. The gyroscopes were constantly in use for an interesting reason. That reason being if you stopped the gyros from spinning, there was ALWAYS the risk that they would not restart. They were gas bearing devices, with no mechanical wear on parts, which is pretty crazy to think about.

I am doing a Research paper on the Hubble Space Telescope right now. anything you could tell me that the NASA sites wouldn't have?

Sadly no. One of the coolest things about the Hubble is that it's purely declassified. All the information that becomes available to us, is then available to you. I think that's one of the greatest things about Space exploration, it's so human, and so without conflict at the same time, that all the knowledge we gain, you gain as well. There's stuff about the politics of the Hubble that NASA sites wouldn't have, but you're probably not interested in that.

Actually I am interested in that. If you could go into more details with the politics, It would be really interesting.

Sure, no problem. The political process of gaining approval for a massive project such as the Hubble is incredibly difficult. We were having meetings with people that you wouldn't think have anything to do with Space. We'd have meetings with different people in Congress nearly every week. Politicians are very concerned with their reputation, and they need to be assured success before they will back your project. If we were to fail, the people who back us would come under fire. We, in some cases, were kicked out of offices because we were "going to tarnish the reputation" of politicians. It was a gigantic struggle. We used the public to gain support as well because the people that would give us funding wanted the support of the people. It was a political struggle in what I believed to be a non-partizan issue.

Thank you for sharing this. Political struggles like this scare me that it will effect our future exploration. Do you think it is/will be a problem or that private companies will be the front of space exploration due to the lack of bureaucracy and issues such as maintaining reputation?

This is precisely why the privatization of space exploration is important. While I believe our government is important and functions relatively well, it isn't great at getting stuff done.

What do you think is next in the realm of space and space-travel?

The future of space travel is, for one thing, a colonization of Mars. We will travel faster, farther, until our goal is reached. NASA isn't one to give up.

Thanks for taking the time to do this. I've read many of the questions and responses - fascinating.

My question: Since the Hubble ended up costing 7-10 billion, it seems the next one could be much cheaper. But my real question is, why don't we send a telescope further out into space where there is less sunlight (and earth-light)? Wouldn't the pictures be much clearer? To me, it seems we should have at least 2 telescopes out there...

The actual reason that we didn't send the Hubble further is that there were always plans to maintain it. Sending it further meant that we wouldn't be able to repair it, which, had we did so, would have resulted in the loss of 7-10 billion dollars. It would result in clearer pictures, but not much clearer than we have now. I'd love to have 20 telescopes, in all different places of the universe, but sadly, money does not permit such a thing. Thanks for reading the questions and answers, I hope people find them interesting. If you learned anything today, or have a greater interest, I've accomplished my goal.

As a NASA engineer, have you ever had legitimate dreams or ambitions of becoming an astronaut?

Is your main passion space or engineering, or a mixture of both?

Oh definitely. I always wanted to be an astronaut. The coolest people I've met because of my job were/are astronauts.

It's very hard to separate the two, because the engineering gets us into space. I'd have to say both. As for my knowledge though, I know more about engineering than I do about space.

At what point did you choose or decide against your own will to be an engineer instead?

Being an engineer was just more plausible for the situation I was in. I don't regret becoming an engineer though, I love what I do.

What is the photo sensor on the Hubble Telescope comparable to in terms of MegaPixels as used in retail cameras?

The answer is going to surprise you. The Hubble's cameras don't even equate to 1 megapixel. Every one of the high quality pixels you see come from the Hubble are actually a composite of (at times) several thousand pictures. The largest pictures the Hubble has taken equate to around 650 megapixels, but any given picture doesn't have more than one megapixel.

Do you have software that composites the multiple images as layers and... will the next iteration of Hubble use the same compositing process but with sensors at the current megapixel level. Lastly, is my question moot because of data transmission requirements of potentially huge image/data files from so far away?

Software does the composite work, but is tweaked if not working properly, because naturally a lot of the pictures will look the same which confuses the machine. As far as I know, it will still be done that way. Data transmission is an issue, but from something as (relatively) close as the Hubble.

Thanks for the responses but more importantly, thanks for the good work you and others have done and continue to do to advance our understanding and level of awe, of our universe.

No problem, if you learned anything, or your interests were heightened, I accomplished my goal.

Got one more for you. This is the text from a post I made to reddit months ago...Care to comment?

as follows: Here's an idea that I've been pitching... Task NASA scientists with solving/developing a cheap renewable energy technology and let them use the profits to fund their programs- like going to Mars. Hundreds of scientists were laid off and they could have kept their jobs, solved a huge set of technical problems, developed some proprietary tech, gotten us off being dependent on foreign governments and kept some really smart people off of unemployment. How hard would this be?

Thanks-

It's a great idea! Here's my problem with it: Most of the scientists at NASA have eventually become extremely specialized in their fields, and some might not know much about renewable energy. I only know a bit about it because my project had to take it into account.

Are you an evil genius?

I am not allowed to disclose that information!

Hi Mr. Weinstein! Thanks for your AMA.

Currently I'm a ME Undergrad at Berkeley, so I'd like to ask a few questions about your education experience if you don't mind.

• Where did you doing your undergrad/grad work? What fields of study?

• What made you choose to get a Masters over your BS? Did you consider going for a PhD?

• At the end of each level of education, did you feel like you were prepared for a career in engineering?

• Do you have any suggestions for finding a good job out of college?

• I'm interested in very hands-on prototype development, fabrication, troubleshooting, and testing. What would be a good starting position to apply for in order to work in that kind of department?

Thanks a lot for your time!

• City College of Engineering in NY for undergrad (this was a much better school at the time) and I did my grad work at the Polytechnic Institute in Brooklyn (also much better at the time). Sorry, I should have clarified, I do have BS in engineering as well as a masters. I didn't go for a PHD because I wasn't interested in teaching or pure research.

• I felt that my education was very good in preparing me for my career. The school I went to was extremely demanding.

• Yes, take a couple management courses. The things that set me apart were my abilities to mange and communicate with people. Make sure you have those skills. Use sites like LinkedIn to broaden your web.

• I'd have you apply to be a test engineer. This is a position where you'd get a lot of hands on experience with equipment.

What improvements could be made to future space telescopes?

I'd encourage you to check out the James Webb Telescope. Improvements could/would exist to detect different spectrums of light, and deeper into the universe.

What is your favorite color?

Also do you think you would ever leave NASA to work with a better funded outfit? Such as the ESA or a privately funded operation.

My favorite color is purple. I have already left NASA to a privately funded organization.

Do you enjoy working there more?

No, sadly I do not. I still love where I work now, but nothing compares with NASA.

Do you have any advice for a computer engineer interested in working with/for NASA? All of the job postings I see are about electrical engineering (antenna design stuff) or computer science, computer engineering is the middle ground of Electrical engr, and comp sci.

Also, thanks for your work which has inspired countless people to become curious about the universe!

I suggest applying for some computer engineering positions which are closely related to computer science. Also, just because you don't work at NASA doesn't mean you won't work with them. Apply everywhere. Take a few management courses, it gets you a long way.

What would you describe as the most profound, "sudden realization" moment you have ever had throughout your career?

That I was working on something that would change the way we view the Universe. I don't know if I can describe this feeling for you but I'll try. It's the realization that your work is so much bigger than yourself. Before, I'd get so caught up in myself and then I realized what I was doing wasn't about myself at all. It's a beautiful feeling knowing that something you helped create, inspires the brightest minds of our generation.

Do you guys ever pull pranks on each other or the people in the ISS.

There were a lot of in office pranks. Never anyone in space though.

What kind of mission would your personally most like to see NASA push for in near future? I realize it will always be a matter of costs and budgets, but if you could choose freely - what would it be? Manned mission to Mars? More rovers? Building a base on the moon? Closer inspecting asteroids? etc.

Manned mission to mars would be great.

Have you ever played Kerbal Space Program?

If so... what are your thoughts on it? Is it really that hard to land something on the moon?

No, never, sorry. Landing stuff on the moon is incredibly difficult, and it's crazy to think that we've nearly perfected it.

Do you ever get teased by names such as Stewfart Weinerstein?

Haha, unfortunately yes. I was known for challenging my superiors and was subsequently known as "The Whining Weinstein."

I will now retort, when someone tells me I am whining, that I was simply "Challenging my superiors."

Exactly!

European here:

What do you think about ESA, and the progress we Europeans making? (not only with Spaceflight, but with things like the CERN too)

Did you punch an moon landing conspirator in the face?

I think you guys across the pond are making fantastic progress. Everything you guys are doing is very important to the scientific community. CERN is a great resource that will be used for years to come. Going there was a very cool experience.

People that don't believe we landed on the moon are holding us back as a species. I was once at a diner in the south with a NASA ID badge on and the waitress refused to serve me because I was lying to the American people. That experience was weird to say the least.

What do you think of jobs for teenagers/adults getting out of college. What is the biggest ratio for jobs to get into.

Is your question for engineering for in general. The biggest fields are probably business. If you're talking about engineering, I'd say that project management is probably the best field to look in to.

what are some of the best schools for someone thoroughly interested in learning about astronomy?

Not sure if you mean as a career or not but here's a couple: MIT (good luck), Cornell, City College of Engineering of NY, New Jersey Institue of Technology

The last two are fairly cheap as well.

What cool new material's can you tell us about ?

Also how can i get something which has been in space, Even a screw would be cool.

You could have worked on the Hubble, I have some solar paneling in my living room. As for acquiring some yourself, no idea.

How did you get into your field of work?

An overwhelming sense of curiosity.

What did you go to school for? How did you get the job as an engineer for NASA? Did you have any prior experience working with systems similar to the Hubble telescope before being employed by NASA?

I majored in electrical and aerospace engineering. I got the job at NASA due to a variety of skills such as managerial in combination with engineering. I had prior knowledge of stuff like the Hubble, but the Hubble was unprecedented technology, I don't think anyone really had prior knowledge of much.

Are there aspects of the Hubble work that are kept classified? Are there certain areas of space that are forbidden from being observed? ie Zeta Reticuli

Every picture is reviewed, and nearly always released to the public shortly after.

Do you have a favorite moment or memory from your job?

When the Hubble was operational again after implementing the new gyroscopes I worked on. I didn't breathe for what felt like hours while tests were being done during the mission.

During your time working on Hubble, how closely did you interact with the nice folks at Perkin Elmer/Goodrich? At NASA do you guys get clearances for system level work? S or TS?

Colleagues of mine worked with them. I did not get the chance, unfortunately.

Are you surprised by how long Hubble, and in fact most NASA missions have lasted compared with their expected lifespans? This may be in part to how ignorant we are in how rigorously you guys test this stuff prior to launch.

I think it is, in part, because people don't realize how much we test these things. If we thought the Hubble was only going last 5 years, it wouldn't have been built. We make sure that you get a return on your investment.

Did you work at the Hubble Control Center behind the Hopkins campus? :P

Sadly no, but great stuff went on in there.

Did being a NASA engineer ever get you laid?

I'll let you decide.

can you please explain the applications and implications of this research into chinese purple?

http://www.magnet.fsu.edu/mediacenter/news/pressreleases/2006may31.html

Unfortunately this is probably beyond my reaches to explain, my colleagues could do a much better job. My best explanation would be that Chinese Purple acts in ways that could explain phenomenon that are very difficult to observe.

If you were put in charge of a project of your choice with a blank check, what would it be?

An expedition to colonize Mars, how cool would that be?!

I'm a first year mechanical engineering student that loves astronomy and dreams of working for NASA or one of the private space companies. I really want to do something space related. Do you have any advice for someone in my position? Is mechanical a field that can get me in or should I look into another field?

Yes, mechanical engineering will get you far. Here's what I'd suggest. Take a couple of courses in management, particularly project management. This is what will set you apart from others, your ability to communicate.

How young were you when you decided you wanted to do this? Or just when you knew you wanted to be an engineer in general?

It wasn't til high scool that I realized that I wanted to be in the engineering field. I had a knack for physics and my teachers encouraged it. Get to know your teachers, they're the best resource you have.

What's one epiphany/revelation you had when working on the Hubble?

Someone asked a similar question below, here was the answer:

That I was working on something that would change the way we view the Universe. I don't know if I can describe this feeling for you but I'll try. It's the realization that your work is so much bigger than yourself. Before, I'd get so caught up in myself and then I realized what I was doing wasn't about myself at all. It's a beautiful feeling knowing that something you helped create, inspires the brightest minds of our generation.

Hiya Stewy!

Why is that when a piece of technology gets designed in 1998, but goes up into space in 2010, it still goes up with old antiquated 1998 tech? Is it really that hard or that big a deal to update some of the tech as time passes?

Lets take Curiosity as an example. Some of the stuff shes packing is simply amazing and jaw dropping. But then I read it has a 2 megapixel camera with a meager 8gb flash drive and I can't help but scratch my head.

Why couldn't that be updated? I'm sure theres a great reason as to why, but it evades me.

Thank you for your time !

I think it's important that people understand this. When we make things, we make it compatible with the technology of the time. Due to how incredibly complex the technology is, this means that we'd have to redesign several aspects of every project if we wanted to have updated technology on launch day. Great question!

Would upgrading something like 8gb to 16gb require that big a rework? Would that really throw that big a wrench into the gears?

I'm not quite sure about something that small. I'm also not that well versed on the Mars Rover. But as for the Hubble, putting a new camera in requires years of work and switching to a different camera in the middle of building puts us back on day one.

How hard was it to make the hubble corrections in space, such as the "contact lens" or the gyroscopes? I mean, it's super-sensitive stuff.

It was extremely difficult, to say the least. It was very demanding for people on the ground, but the actual work in space wasn't that challenging. It was more of the engineering than the actual work that posed a challenge.

How much better will the Hubble replacement be. (2018?)

Not only better but much different. The James Webb will be a fantastic tool for discovery.

I've always wanted a NASA engineer AMA, thanks for doing one! My questions:
- Are there any non-american engineers working directly for NASA? (I'm from the UK)
- Did you get to choose which projects you worked on to any extent?
- Do you think nuclear thermal rockets will ever make a comeback?
- Would proven experience in another field (such as defence) compensate for having only a BEng?

You must be a U.S. citizen to work for NASA. However, you might want to check out this site if you would like a job that works in contact with NASA.

I really didn't get to chose the projects I worked on. You can request a certain project, but it doesn't go a long way as far as actually getting you to work on any given project.

Yes, nuclear thermal rockets, as far as I'm concerned, should and will be used because they are a very efficient source of power in terms of output to mass.

Does NASA have problems with entrenched job-for-life people who are not concerned with exploring the universe, but just want to control others and make decisions that increase their own status? Is that less of an issue in the private sector where they would get fired?

Not in my experience, no. People at NASA are there for the purposes of advancing our species. It is an issue of the private sector, but is not limited to engineering.

In your opinion, what was the most amazing discovery the Hubble telescope did?

That's a tough one. Being able to observe close to the edge of the universe (not one discovery in particular, I know) is probably highest on my list.

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I have no idea. Do you know if it's heavy or is lighter than you'd think? Because that would help me figure out what the material is.

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Sorry, I'm really not sure. Sorry I couldn't help.

What university did you go to?

I went to City College of Engineering in New York and then Polytechnic Institute of New York. I was very poor growing up, and couldn't afford to go to better schools.

I am a little less than fortunate right now, and had to go to a less academically prestigious school than I wanted. But it's awesome that you ended up at NASA!

Never lose that drive, it'll get you far.

How does it make you feel knowing that you helped to forward the exploration of outerspace with the design and creation of the H.T.? I know sometimes it gets a bad wrap for image quality or what not, but some of my most favorite images of space ( specifically the one with the galaxy cluster) have been captured by the H.T. Either way, Kudos on a job well done.

This is my best description of the feeling, as stated in a previous post:

That I was working on something that would change the way we view the Universe. I don't know if I can describe this feeling for you but I'll try. It's the realization that your work is so much bigger than yourself. Before, I'd get so caught up in myself and then I realized what I was doing wasn't about myself at all. It's a beautiful feeling knowing that something you helped create, inspires the brightest minds of our generation.

Was the giant reflector for the Hubble was made by The Steuben Glass Works in Corning NY?

I don't believe so.

How would a new and larger telescope then hubble benefit us? And what advances have been made, to justify sending another telescope up there?

It would allow us to see things that previously were unable to be seen. This would lead to fantastic and unprecedented discoveries. As for justification, I the discoveries we would make would lead to an extreme amount of advances in other scientific fields as well. They can't be predicted, but their bound to happen.

Hello Steward,

I'm fascinated by the universe and everything in it. I like spending time just thinking about what we are, where we come from and where we're going. Do you think we'll ever find out what really happened at the very beginning of everything (if there actually is one) ?

I'm not a religious man, but part of me is glad that these aforementioned questions remain unanswered. This mystery gives way to a lot of beautiful ideas like a heaven, reïncarnation or some other form of an afterlife. How do you feel about this? What if you could prove we're nothing but stardust, a collection of molecules. Don't you think that solving the mystery of the universe and our own existence would cause some sort of emptiness and feelings of meaninglessness?

Don't get me wrong, i'm dying to know what happened, but i also think it spoils the mystery ;)

I think that our discovery of certain things is inevitable. I do not think though, that our discovery of these things takes beauty out of life. I think they add beauty. People ask why I haven't adopted a nihilistic view of life because I want answers, I think that the premise is ridiculous. I think if we stopped to admire the utter improbability of us, we'd stop fighting.

• How many people were fired for the mirror problems of Hubble?

• Were those the right guys to fire in your opinion?

• How much did the repair-mission cost?

• Who came up with the idea for this mission?

• What do you think of the JWST?

• No people were fired for the mirror problems of the Hubble. Engineers make mistakes but they were unintentional. No one deserved to be fired in my opinion.

• The repair mission that I worked on cost $100 million dollars excluding the cost of actually getting the stuff into space.

• The rescue mission was more of an obvious necessity than an idea. The science behind it was created by several NASA scientists including myself.

• I think it's fantastic. A great advancement into the universe around us.

As a Canadian disillusioned on job opportunities in space-related fields of work, have you worked with the Canadian Space Agency before, or were there any Canadians working with you on the Hubble project? (Thank you very much, for this AMA, it is incredibly interesting!)

You have to be a U.S. citizen to work at NASA. We did work with the CSA a lot in other projects as well as the Hubble. I'd get involved with them if you can, they're a great organization.

What was your job before this and what degree did you get?

I have two degrees in Aerospace Engineering. I worked for a small consulting firm before NASA.

What is the future of space travel?

The future of space travel is, for one thing, a colonization of Mars. We will travel faster, farther, until our goal is reached. NASA isn't one to give up.

So, as a high school student interested in astronomy and physics, how would you go about getting to work at NASA eventually? College, majors, etc.

I majored in Aerospace Engineering. It's important that you take some courses in management too, it will set you apart from others.

Approximately how far will the JWST be able to see?

The goal is that it would be able to see the far reaches of the universe. Basically, as far as we can see.

What is your educational and employment background before Nasa? Basically, what was your path to get there?

I was employed by a small consulting firm before I worked for NASA. As for my educational background, I majored in Aerospace Engineering.

How have the advances of the Hubble helped with the James Webb Telescope?

Many of the engineering techniques developed on Hubble were fundamental do developing the James Webb. For instance, the optics and pointing control systems are largely influenced by the Hubble.

Does NASA work with ESA? Which agency do you think contributes more to space exploration?

The ESA does fantastic work and they greatly help NASA a lot. They definitely help the most of any foreign agency.