Scale & distance01
A light-year is a distance. What does that let us understand?
Turn an intimidating unit into a useful tool for thinking about travel, delayed information and the limits of a cosmic map.
Read the notebook 1,165 words ↗EIGHT ORIGINAL ASTRONOMY ESSAYS
Begin with a question.
Follow the light.
Clear physical explanations, worked thought experiments and primary references. No invented observations or claims of current institutional affiliation.
Published 17 October 2026. Each essay contains 1000–2300 words of main text. The historical archive is a separate Greek and English source collection, not an earlier publication record of these new essays.
Scale & distance02
Parallax: finding distance from a very small change of viewpoint
How a known baseline turns an angle into a stellar distance — and why a noisy parallax cannot always be inverted casually.
Read the notebook 1,148 words ↗Light & instruments03
A spectrum is a measurement, not just a rainbow
Read wavelength, line strength and motion without confusing a detector's output with a ready-made inventory of a star.
Read the notebook 1,175 words ↗Stars & origins04
Making a star: gas, gravity and the problem of losing energy
Why a cloud does not simply fall into a finished star, and how cooling, rotation and feedback shape the route to fusion.
Read the notebook 1,219 words ↗Stars & origins05
Reionization: asking how the first sources changed the space between galaxies
Separate neutral atoms, ionising photons and expanding regions of influence before interpreting a headline about the early universe.
Read the notebook 1,226 words ↗Light & instruments06
What colour is a telescope image? Read the filters before the palette
A practical way to distinguish measured wavelength bands, display choices and the physical claims an astronomical image can support.
Read the notebook 1,205 words ↗Measurements & practice07
Bright here, powerful there: separating flux, luminosity and distance
Work through the inverse-square relation, magnitude differences and the extra information needed before a faint star becomes a distant one.
Read the notebook 1,204 words ↗Measurements & practice08
An observing log that another reader can actually use
Record the target, time, method and limitations so that a memorable night becomes an interpretable observation rather than an unsupported result.
Read the notebook 1,207 words ↗