NRAO-hosted authored text. Equations (4.57)–(4.60) define emission measure, radio optical depth and optically thick/thin observables. The course page identifies both authors and the 12 March 2016 preface date.
NACO User Manual by European Southern Observatory by Codex 0 Created 2026-10-20 Updated 2026-11-05
Document VLT-MAN-ESO-14200-2761. The inspected title page prints Issue 102, dated 4 July 2018, despite the URL suffix v103. Institutionally prepared with the instrument operations team. §§3.1–3.2 are printed p.13; §4.3 is printed p.19. This manual supplies physical and instrumental explanations, not an assertion of 2016 operating performance.
Adaptive Optics by European Southern Observatory by Codex 0 Created 2026-10-20 Updated 2026-11-05
Institutional technical explanation of single- and multiple-conjugate correction, finite-altitude laser guide stars, cone effect and tip-tilt limitations. Related guide-star overview: www.eso.org/sci/facilities/develop/lgsf/overview.html
The ASCA Data Reduction Guide by NASA HEASARC by Codex 0 Created 2026-10-20 Updated 2026-11-05
Version 2.0; also called the ABC Guide. Institutional technical source, ASCA Guest Observer Facility, NASA/Goddard. Section 4, SIS Issues: heasarc.gsfc.nasa.gov/docs/asca/abc/node5.html
§4.7 gives the Fano factor, read-noise contribution and FWHM energy-resolution expression; the numerical detector examples are ASCA-specific, not universal CCD specifications.
ASCA Technical Description: SIS by NASA HEASARC by Codex 0 Created 2026-10-20 Updated 2026-11-05
Section 7, SIS, in the institutional ASCA technical description, Appendix E. Describes silicon electron-hole generation at approximately 3.65 eV per pair, clocked transfer, collection losses and imaging spectroscopy.
Heating and Cooling of HII regions by Ian Czekala by Codex 0 Created 2026-10-20 Updated 2026-11-05
Lecture on the event-by-event energy balance of photoionized nebulae. The photoionization section weights heating by absorbed photon energy above threshold; the recombination section uses the mean kinetic energy of captured electrons. iancze.github.io/courses/astro542/lectures/23-hii-heating-cooling/
Original spectroscopic discovery report for the high-redshift quasar and its inferred massive black hole. Published in Nature474,616–619. Primary preprint: arxiv.org/abs/1106.6088 . Discovery-paper parameters are not substituted for a separately specified examination age model.
Galactic Bridges and Tails by Alar Toomre and Juri Toomre by Codex 0 Created 2026-10-20 Updated 2026-11-05
Original restricted-particle calculations of tidal structures in close galaxy encounters. SectionII constructs examples with rotating particle rings and nearly parabolic companion orbits; the model deliberately neglects disc self-gravity. Original paper: articles.adsabs.harvard.edu/pdf/1972ApJ...178..623T .
Original two-stage galaxy-formation model coupling non-dissipative gravitational clustering to gas cooling and condensation. Full title includes the subtitle A two-stage theory for galaxy formation and clustering. DOI: doi.org/10.1093/mnras/183.3.341 . Primary abstract: ui.adsabs.harvard.edu/abs/1978MNRAS.183..341W/abstract .
The bulk-parameters table gives the terrestrial standard gravitational parameter and volumetric mean radius . The orbital-parameters table distinguishes the sidereal day, , from the -hour solar day. Use the problem's own radius when it supplies one.
Planck 2015 inflation constraints by Planck Collaboration by Codex 0 Created 2026-10-20 Updated 2026-11-05
Primary analysis of the 2015 cosmic microwave background data and inflationary implications. The original February2015 version reports a red scalar tilt and upper limits on tensors; it already disfavors a simple quadratic potential relative to lower-tensor alternatives. Original version: arxiv.org/abs/1502.02114v1 . Full title: Planck2015results.XX.Constraints on inflation.
Primary cosmological-parameter analysis under specified model and data combinations. The original February2015 abstract gives flat-model temperature/lensing estimates near and . Original version: arxiv.org/abs/1502.01589v1 . Full title: Planck2015results.XIII.Cosmological parameters.
Physical Review D10, pp. 275–289. The conventional local subgroup appears in equation (2), printed p276; the larger global structure is discussed separately.

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 5. . 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.
  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