Project Earendel is an open source rocket project with the aim of building and flying a liquid-fuelled rocket, capable of flying to 100km in altitude (the definition of space!) on a suborbital trajectory. What is open source you say? Well, everything about the rocket development process, such as design, calculations, facts etc, is shared in the public domain, everything is published and therefore, you are welcome to use it all. So, there is no reason why you could not theoretically build your own rocket using the same technology, either identical or modified. The project is headed by Llyod Droppers and Jasmine Cashbaugh, both have extensive backgrounds in the aerospace industry and have worked on many rocket projects in the past.
The Earendel Rocket is 6″ (0.15m) in diameter and 8.5ft (2.59m) in length, it is fuelled by liquid oxygen and isopropanol alcohol that is pressure fed into a film cooled engine producing 200lbf (889N) of thrust. It uses Arduino hardware to run the various electronic systems. The project went to Kickstarter to raise the funds required to make this rocket a reality, but unfortunately it failed to meet the goal of USD$150,000. With the campaign falling short, the project is still ticking along albeit at a much slower pace. Weekly blog posts now entail general rocket design information and I must say these in itself are very informative to anyone who is looking for knowledge on liquid-fueled rocket design. Being an open source project, all the documentation of the project so far is available on the website, you can download all the information and files required to 3D print and build your own spark torch igniter, a common and well-used way of igniting the main combustion chamber of a liquid-fueled engine.
For anyone interested in sending a rocket on a suborbital trajectory, or just wanting to know more about what it takes to do that: start at the very first blog post and read through to the end, there is a wealth of information and will get you at least on the way with all the technical terms and lingo that surrounds a liquid-fueled rocket. It would be fantastic to see this project have another go at getting funded and succeed. (My apologies for not mentioning this in my rocket project post overview)