Editorial policy

Last updated 6 Oct 2026

UULKA publishes two kinds of content: automated forecasts and written guides. This page explains how each is made and what we will and will not do.

Forecasts and scores

• Sources. Weather values come from MET Norway's Locationforecast service. Sun, Moon and planet positions are calculated locally with Astronomy Engine. Aurora outlooks use NOAA SWPC's Kp forecast. Satellite orbits come from CelesTrak, the space feed from NASA and the Spaceflight News API, and the star charts from the d3-celestial catalogue. Attribution is shown on every page.
• Method. The scoring rules (weights, thresholds, caps and the wording of verdicts) are published in full on the home page and in How to read the UULKA score. Scores are produced by software from those rules; nobody adjusts an individual night's score by hand.
• No invented data. If a forecast does not supply a value, UULKA leaves it out of the calculation and says so rather than guessing. Haze and transparency are labelled as estimates. UULKA does not display "seeing".
• Uncertainty is shown. Nights beyond the hourly part of the forecast are marked "less certain", and an offline or out-of-date forecast is labelled as such.
• Independence. Advertisers, sponsors and affiliates cannot influence, pay for or request a change to any score, verdict or guide.

Written guides

• Guides are written and reviewed by Digitallo. Each shows an author, a publication date and, when it changes materially, an updated date.
• Factual claims about astronomy are checked against primary sources such as observatory, agency or catalogue pages. Meteor shower peaks and eclipse dates are checked against the International Meteor Organization calendar and published eclipse predictions before they are added to the events list.
• We do not publish medical, safety or legal advice beyond sensible outdoor-observing precautions, and we always say never to look at the Sun without certified eclipse glasses.

Advertising

UULKA is free to use and is meant to be supported by display advertising. Ads are always separate from and visually distinct from forecasts and guides, never placed inside the score, and never described as recommendations. We do not sell placement in scores. See the privacy policy for how advertising and cookies are handled.

Corrections

If you find a mistake, tell us. We will verify it, fix it as soon as we can, and add a note to the page when the correction is significant. Forecast inaccuracies that come from the weather itself being different from the prediction are not errors we can correct, but we are interested in patterns, for example a place where cloud is consistently over-forecast.

Updates

Forecasts refresh automatically whenever MET Norway publishes a new model run, normally about once an hour. Written pages carry their last-updated date.