GÉANT is a high-speed research and education network that connects national research and education networks (NRENs) across Europe and beyond. It facilitates collaboration and data transfer among researchers, institutions, and organizations in the academic sector, providing a backbone for advanced internet services and applications. GÉANT supports a range of activities, including high-capacity data transfers, collaboration on scientific projects, and the deployment of innovative technologies.
An astronomical transit refers to the event when one celestial body passes in front of another, as observed from a particular vantage point, typically from Earth. This phenomenon can occur among various celestial objects, such as planets, moons, or even stars. The most common types of transits are: 1. **Planetary Transit**: This occurs when a planet passes directly between a star and an observer, causing a temporary dimming of the star's light.
AMSRefs is a reference management tool developed by the American Mathematical Society (AMS) for use in mathematical writing. It helps authors manage citations and formatting in their documents, particularly those written in LaTeX. AMSRefs provides a way to create bibliographies and ensures that references are formatted according to the AMS style guidelines. The tool simplifies the process of citing mathematical literature by allowing users to generate references in various formats, making it easier to prepare manuscripts for submission to journals or for inclusion in personal projects.
Local group by Ciro Santilli 40 Updated 2025-07-16
The basically composed of only the Andromeda Galaxy and the Milky Way. Every other galaxy is a satellite of those two.
"Chinga" is the name of the 10th episode of the fifth season of the television series "The X-Files." It originally aired on January 12, 1998. The episode was written by Stephen King and features a story revolving around a cursed doll that has a mysterious and malevolent power over its owners.
Andromeda Galaxy by Ciro Santilli 40 Updated 2025-07-16
First proper nearest galaxy to the Milky Way. Everything in the middle in the Local group is either a satellite of the Milky Way or Andromeda.
Many Andromeda satellite galaxies are simply numbered Andromeda II, Andromeda III and so on.
As described on Wikipedia, the observational history of Andromeda is fascinating. Little by little, people noticed that it had a different nature to many other objects observed on the sky, and the hypothesis that there are other galaxies like ours grew in force.
Part of our fascination with Andromeda is due to how similar in size and shape and close it is to the Milky Way.
It is clearly the only thing so large and so close.
Andromeda is, without a doubt, our sister galaxy.
One can't help but wonder if there is some alien looking back at us when we are looking at them through our telescope.
Andromeda is also the furthest object from Earth that can be seen with the naked eye.[ref] Not surprising, as it literally shines with the strength of a trillion suns!
Figure 1.
Highest resolution image of Andromeda as of 2015, taken by Hubble
. Source. Source also says it was the highest resolution image every released by the Hubble. This goes to show how fascinated people are by Andromeda. And there is good reason for it.
Video 1.
Andromeda Shun from Saint Seiya performing his Nebula Chain attack
. Source. The original Japanese music actually says "Nebula Chain" in English. The Andromeda Galaxy is shown on the back, the chain appears to go all the way to it and back towards the evil guys' head. Not very relativistic, but so be it.
Video 2.
Andromeda Galaxy with only a Camera, Lens, & Tripod by Nebula Photos (2020)
Source. Good job! Gives a good idea of the low end approach.
Point particle by Ciro Santilli 40 Updated 2025-07-16
This idealization does not seems to be possible at all in the context of Maxwell's equations with pointlike particles.
Proxima Centauri by Ciro Santilli 40 Updated 2025-07-16
It is so close that we can notice its proper motion, and its distance to us will vary significantly across a few tens of thousands of years!

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact