We are building a map
of what we do not yet know.
An open atlas of real sky-darkness measurements, made by real people at real sites. Most cells are blank. That is the point. We want your readings — named, dated, and permanent.
What we are building
The World Dark Sky Atlas renders the night sky's honest state — not a model, not a satellite average, but a grid of cells each holding an actual human measurement. Where no one has measured, the cell is empty. We are not filling it with grey. The map tells the truth.
Our first region is Texas. It will expand as contributors add readings. Every cell you fill carries your name, your site coordinates, and the date you stood there.
What we need from you
We are reaching out specifically to the kind of observer who checks the actual data before they drive two hours into the dark. You know how to read a Bortle scale. You have a site you trust. We want:
- A naked-eye limiting magnitude or SQM reading at your site
- Coordinates and elevation (phone GPS is fine)
- The date and approximate local time of astronomical twilight when you measured
- One sentence on conditions — moon phase, haze, what you were dealing with
That is it. No signup required to submit a reading. No gear list. We are not asking you to install anything.
Every reading you submit fills a cell that has never been filled. It ships with your name attached — not a username, your name — and it stays there permanently. We count every honest act aloud, credited to its doer.
Bortlebug free beta is open
Bortlebug is our first tool built on this data layer — a personalized astrophotography forecast for your exact site, your gear, and your targets. It is in free beta now. The free plan is a real plan: one location, one telescope, one 3-night forecast window, full report every time.
If you submit a site reading, Bortlebug already knows that cell. Your first forecast will pull from your own measurement, not a satellite estimate.
Submit a Reading Try Bortlebug FreeA note on how we work
We are a small shop. We move on the assumption that the people reading this paragraph are worth being honest with. We will not send you marketing emails if you submit a reading. We will not sell your site coordinates. The atlas is open and we intend to keep it that way.
If you have questions, corrections, or a site you want to discuss in person, reach us at atlas@lonestarobservatories.com.