# Light Left

> Find the star whose light left the year you were born. List the people for a card - a name and a birth month each - and the page finds each one a real naked-eye star whose light arriving now left it around their birth month (its distance in light-years is about their age), with the measured error bar and an honest tag, then joins the stars into one constellation on an all-sky atlas plate.

URL: https://light-left.skillsafe.ai/
API: https://light-left.skillsafe.ai/api.html

## What is free (runs in the browser)
- Matching: 374 stars brighter than about magnitude 5.6 out to about 108 light-years, with distances from Hipparcos parallaxes (the 2007 new reduction, VizieR I/311) and their errors. A match is "on the year" when the age falls inside the star's error bar or within half a year; "near" when off by up to about two years more; a "stand-in" otherwise; "still on its way" for anyone younger than the nearest star's light (about 4.3 years), with the month that light arrives.
- When and where: the month a star stands highest at about 9 pm (approximate), how high it stands and in which direction from a chosen latitude band, whether it never rises or never sets there, brightness and colour words.
- Drawings: an all-sky star plate (the band that never rises shaded, the card's stars ringed and joined in list order) and a light ruler of ages against distances with error bars.
- Exports: plate SVG, CSV, Markdown and JSON.

## What is metered (one task)
- task "card": one verdict by a fixed order - true_light (every person on the year), mostly_true (at least half), stand_ins (otherwise) - plus a title, a headline, a caption and a finding line per person, a footnote and a closing line. The page matches the stars and owns every number; the model writes only the words, and the page re-checks every reply. Runs on gpt-terra.

## Honesty
- Nobody can buy or name a star; the card only follows the light. Evening months and heights are approximate. The stars are not astrology.

## Sources and credits
- Built on the SkillSafe skill @claude-office-skills/infographic (https://skillsafe.ai/skill/@claude-office-skills/infographic).
- Star data: Hipparcos new reduction (2007, VizieR I/311); names, designations and constellations from the HYG database v4.1 (astronexus, CC BY-SA 4.0). The page's star list (https://light-left.skillsafe.ai/stars.js) is shared under CC BY-SA 4.0.