Solar thermal uses mirrors to concentrate light anyway. Fresnel lenses are kind of messy in that the scatter the light a lot, so you can't shrink the PV as much if you were using a mirror.

I am a Mech E. While that amount of displacement may not be noticeable to the user, it is noticeable to the control system and could certainly throw things off, depending on the control system used. It would need to be accounted for.

1. Yep, that is pretty much how finger movement would have to be done. And probably other joints where practical.

2. Springs have a very poor energy density compared to other methods and this would not be practical. Relevant here to point out I have a BSME degree. Sorry.

3. EMDrive: Probably doesn't work. There needs to be a lot of evidence before it can be accepted. Photon propulsion is well known, the problem is that they are claiming a much higher force / efficiency than could be achieved with radiation pressure. Which is why it basically appears to violate the first law of thermodynamics.

4. " I came to the conclusion that the reason our mathematics were all wrong is because we adhere to a vehemently cartesian point of view " There are at least three statements in that sentence that are totally incorrect.

5. Relativistic speeds. We are going relativistic speeds - relative to the other side of the universe. It's moving away from us at nearly the speed of light and we are from it. Look up the Hubble Constant.

Agreed. I don't know why people see Greece as a victim. It is clear that austerity was too tough and the conditions of the bail-out should have been very different, but they still got bailed out when they were in deep trouble. Greece is better off that the IMF & ECB stepped in.

Deanonymizing may slow it down, but I don't think it will prevent users from being nasty to others. Slowing this down is still worth pursuing though. Do you slow down the rate at which hub-wheeled users generate tags?

Can you let posters remove community tags? I'm new to this site but someone could always submit the same link with different tags, right?

I see the inevitable scenario when someone tags a post with #israel, and someone else wants to tag it with #palestine, or #freepalestine. Do you let the original poster control the conversation, or just let people fight over it?

Thanks for chiming in. I have done my time at NASA as an intern and I never want to go back. Private industry is so much better. We still have our procedures and checklists, but we write them with a mind to get things done, not an end unto themselves.

Nice. Is it pronounced the same as palantir?

Not really an opposing view but this article details the direction the country has been moving in. America has one thing that many other countries don't, we talk about racism, how to prevent and improve the lives of minorities. Many people around the world think that racism is an american thing, while sweeping their problems under the rug.

http://www.economist.com/news/united-states/21650533-what-dead-white-man-can-teach-america-about-inner-city-decay-fire-and-fuel?zid=315&ah=ee087c5cc3198fc82970cd65083f5281

Is there some kind of regulation you feel commercial rockets are currently lacking? There are already multiple licenses from the FAA and FCC required to launch a rocket and put a payload in space. NASA has deep involvement as a customer if it is their payload or their astronauts or coming close to the ISS.

Nice! Can you share some of the stuff you are working on?

My experience at NASA ranged from good to horrible. The project I posted above wasn't made at NASA, since I was working for a private contractor, and I can say I enjoyed it much more. I was able to work on a real hardware project, had a budget, and actually had some control over my IT situation.

If you are interning on a good project at the Right center it can be tons of fun. I don't think I made a post for the one that wasn't.

Good question, I would guess not. The AXEL rover project was ended shortly afterwards (Their technical lead left to SpaceX). I hope that someday a derivative of that is used on Mars, because accessing the sides of cliffs is very important to understand the geological timelines.

As far as the drill goes, I don't think anyone will look at it as inspiration for future projects. It was made as a cheap demonstration project. I'm sure there will be drills like it, but I don't think they will be derived from this.

It was some high performance stereo-lithography resin. I can't remember the name, but it was marketed for wind-tunnel use.

Those aussies seem so chill.

I've worked for NASA. Getting things done was difficult and frustrating. That's why I'm in the private space industry now.

The Space Shuttle, despite the enormous amount of money spent on it, didn't have a wonderful record either. Flight 25 was the challenger disaster. This was Flight 19 of the Falcon 9, which has been rapidly improving since the first flight.

9) There are no downvotes and "sharing" is NOT the same thing as upvoting. When you click the dot, it means "I want my friends to see this" not "I approve."

Wait - but how do I tell someone over the internet that I want to STAB THEM IN THE FACE?

I'm kidding (nervously laughs), but coming from the adversarial reddit community, how do disagreements play out?