The Elara Handbook

The Elara Handbook#

Welcome to Project Elara! Project Elara is a mission of a team of committed scientists, engineers, and talented people, working across many different fields, to pass down a better world to our future generations.

Who we are#

We are organization committed to developing open-source technologies that we believe can create a better future. Our current research focus is in developing a space-based solar power system that is 100% open-source and dedicated to a sustainable, resilient, and affordable energy future. We choose to make all of our work open-source, because we want that future to be for everyone.

These are indeed lofty goals, and we realize that even trying to begin is hardly simple. Therefore, we work as a team to accomplish this mission together. To advance, share, and preserve our collective knowledge and expertise, and to build on each other’s work, we have put together this encyclopedic book. Everything you’d ever need to learn, develop, or contribute to Project Elara can be found here. And we dedicate this book to the world: the Project Elara Handbook is released into the public domain and free to view, share, remix, and download, forever.

Want to give us feedback?

Please let us know so that we can improve the Handbook! Just file a feedback request on the Handbook issues tracker with the label feedback and we will respond there once we can!

The newcomer’s guide#

If you’re new to the Project, we are very glad to have you join us! To get started, please read How to get started in the project, which contains a complete, step-by-step guide on getting started with the Project.

Once you’ve gotten started, reading the Elara Handbook is the recommended way to learn more about the science behind our work. That said, we understand that reading technical and scientific documentation can easily be quite confusing, so we have organized the Handbook to require minimal prerequisite knowledge and background to read. For this, the Handbook is split into three main sections: A Guide to The Basics, A Guide to The Specifics, and A Guide for Experts. We’ll also refer to them as just “The Basics”, “The Specifics”, and “The Expert’s Guide” for short. They can be read in order, or read separately. While everyone’s learning needs are different, we give some suggestions for which of the sections to read based on your interests/comfort level with the technical sciences:

I just want to learn about Project Elara, but I’m not interested in the technical stuff. In that case, reading just the basics/about/index chapter in “The Basics” should be enough!
I want to learn the technical stuff, but I’m unfamiliar with calculus, introductory physics, or computer programming. In that case, we recommend reading all the chapters in “The Basics” before progressing any further. We also recommend reading at least some of the chapters in “The Specifics”. While reading everything in this chapter will provide you with a thorough understanding on which to do research, we understand that is not for everyone, so read according to your interests and time
I have good familiarity with calculus, introductory physics, and computer programming (in at least one language). In that case, we recommend just skimming through “The Basics” for a basic review. Afterwards, we strongly recommend reading through as much of “The Specifics” as possible. This section covers all the theoretical and applied foundations for understanding the Project’s core research, and explains the Project’s research. However, it is not necessary to read anything beyond.
I am strongly interested in theoretical or computational physics, and have a strong math and physics background. In that case, you should be set reading just the basics/about/index chapter in “The Basics”, then jumping straight to “The Expert’s Guide”.
I am a developer and just want to work on code. In that case, we recommend reading the first part of “The Basics”, and then jumping straight to the expert-guide/developer/index. You may then choose to read whichever parts suit your interest/are needed for the work you plan to do.

We are so grateful for each and every one of our team members, and everyone’s contributions, no matter how small, will be tracked and (eventually) added to Contributions at the end of the book. Your work brings us one step closer to changing the world for the better.

PDF version#

For offline usage, an older PDF version of this book can be downloaded from elaraproject/elara-handbook, but be aware that it is significantly outdated in many areas. We are currently working on updating our infrastructure to support PDF builds for the newest version of the Handbook.

FAQs#

I don’t understand the code within the Handbook. What is it there for?
- Many pages in the Handbook contain inline code that does scientific calculations, generates graphs and plots, or solves particular equations. You do not need to understand them, but we will go over programming within the Handbook so that the code makes more sense.
Why is there so much incomplete/misplaced/undecipherable content?
- We are a small team and though we want to produce documentation and work of the highest quality, our time constraints mean that the Handbook does have sections that seem out of place or are far too rushed. The Handbook is a work-in-progress and we highly encourage reporting any issues you find to our issues tracker.
Do I have to read through everything? This seems like a lot and I’m not sure I can read this much.
- No, you don’t have to read any more than you feel comfortable with! It’s okay to skip sections or read only a small portion of the Handbook. We wrote this Handbook to be comprehensive because (among other reasons) we wanted to explain everything possible so that someone reading wouldn’t get lost when we explain our research. But there is no need to learn everything or read it all!
I’m reading the PDF version of the Elara Handbook and I notice a bunch of stuff that doesn’t look like it should be there or weirdly-formatted stuff. What’s that about?
- The web version of the Elara Handbook is the primary version (for now) and it includes internal links and HTML content that doesn’t always translate super well to PDFs. While we try to make the two compatible, we unfortunately haven’t had the time to look over everything. Again, we encourage you to report issues you find to our issue tracker (the link is given above).
The chapter numbers in the PDF don’t line up to the web version or the titles in the Handbook, why is that?
- Our PDF generator tool works in a way that doesn’t distinguish between actual chapters and introductory pages. We are trying to figure out a way to solve this issue, but it will take some time, and again, please report this issue (and any similar ones) so we know which places need fixing.

Quickstart for developers#

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Wanting to edit and add to the Handbook? This book is written using Jupyterbook, a Python-based tool for making scientific books containing runnable code. The source code is hosted on Project Elara’s Codeberg in the elara-handbook repository. To edit the Handbook, ensure you have Git installed, and then clone the repository:

git clone https://codeberg.org/elaraproject/elara-handbook
cd elara-handbook

To build the book locally, ensure you have Jupyterbook installed, then, with a terminal open to the root directory of the repository, run:

# You MUST run this in the ROOT of the Git repo
jupyter-book build book/

Then you can start writing! We recommend using a markdown editor like Obsidian which makes editing much more convenient, but this is not strictly necessary. Simply follow the below instructions:

To write a new section, first switch to a new editing branch with git checkout -b YOUR_NEW_BRANCHNAME (replace YOUR_NEW_BRANCHNAME with an appropriate name for the branch as you see fit)
Copy a template from the templates/ folder in the repository root and copy it into one of the directories (e.g. basics/, specifics/, etc.)
Then rename it to a suitable name and add the filename to _toc.yml located in the repository root in the appropriate section
You can now start editing! Remember to commit and open a pull request (Codeberg provides automated tools for this) so we can merge in your changes!

Obsidian-specific settings#

If you are using the Obsidian to edit pages for the Elara Handbook, there are some settings that provide a more comfortable editing experience, which we provide instructions for below.

Hide build files and other artifacts#

Install the File Ignore plugin and enable it. Then in the plugin settings (in the “Rules” textbox) enter the following:

temp/
*.tmp
.DS_Store
Thumbs.db
_build/

Afterwards press “Hide files” and Obsidian will stop indexing the build directories, as well as config files. Note that it is also very important when building the book locally to modify the build command to:

# Again this must be run in the ROOT of the repository
jupyter-book build --path-output book/._build/ book/

This is because using the standard command jupyter-book build book/ clashes with the file ignore plugin and makes it not work!

Hide the inline titles#

Go to Settings → Appearance and disable “Inline Title”.

PDF export#

The Elara Handbook can also be read as a standalone PDF. For this, you’ll need to have LaTeX installed - we recommend using the MikTex installer for LaTeX to install LaTeX - as well as the make utility installed (on most Linux OS’s this should already be preinstalled, on macOS you need to install it with xcode-select --install, and on Windows follow the instructions at Make for Windows or install it from Cygwin). To build the book PDF, make sure you’re in the root directory of the repository, then simply run:

jupyter-book build book --builder latex

Tip

If you choose to use the Obsidian markdown editor, just open the book/ subfolder of this repository as a vault, and then you can edit it like any other Obsidian markdown vault. In addition, we highly recommend installing the obsidian-latex plugin, as it provides support for custom LaTeX commands (such as \unit for typesetting physical units) that are not shipped with Obsidian by default. We have already set up a LaTeX snippets file that should load automatically upon installing the plugin, so you can get started as fast as possible.

More developer information#

Note

For developers working on Windows, it is highly recommended to configure Git to automatically handle line-endings via git config --global core.autocrlf true before editing anything. See this article here which explains why it is necessary.

All material in the Elara Handbook is dedicated to the public domain. You may freely use, redistribute (free or for a fee), copy, modify, and (most importantly of all) learn from this book. Just be aware that this book cannot be copyrighted, patented, or claimed as your own work (as it is inherently in the public domain). You may also make proprietary modifications to this book and/or its included source code and sell it, use this book commercially, or include this book as part of a product. We, however, do not encourage the practice, as it is fundamentally against our values, and we would hope that if you derive profit from this book, you contribute some part of your profits to helping Project Elara and its mission.

License#

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The Elara Handbook is dual-licensed under the Unlicense (Public Domain License) and Creative Commons CC0 License as it contains both traditional book content and included executable code. In situations where an ambiguity arises as to which license should be applied, whichever of the two below licenses is more permissive will be regarded as the sole license to be applied across the whole work.

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