How we check

Sources, in order of preference

1. The company or agency itself: its own website, press release, payload user guide or price estimator; its SEC filings (10-K, 10-Q, S-1, 8-K); NASA, its Office of Inspector General, and the US Government Accountability Office (GAO); FCC filings.
2. Archived copies of those pages from the Internet Archive's Wayback Machine, for prices and dates no longer on the live page. Each archived price links to its copy.
3. Press reports (Payload, SpaceNews, Reuters and others) only when no primary source exists. They are marked "press report" next to the source.

We do not use Wikipedia, aggregator sites or AI summaries as sources.

Dates

A source's date is recorded as the source gives it: a day, a month or a year. Dates of our own reads (for example "read November 1, 2026") are New York calendar dates. When a company states a target such as "Q1 2027" we record those words, not a guessed day.

Launch dates and slips

For every station and mission we log each target the company states, with the day it was stated and a link. Old entries are never edited or removed. A page shows the current target first and the full history under it.

Prices

Prices are in the currency the company sells in; nothing is converted. Where we adjust for inflation we use the US Consumer Price Index for All Urban Consumers (CPI-U, series CUUR0000SA0, Bureau of Labor Statistics), from the month a price was published to the latest month available, and say so under the table. Price per kilogram is our arithmetic: the published price divided by the published maximum payload from the same page.

What we do not do

• No estimate is shown as a fact; our calculations are labelled.
• No opinion about a company's plans: we report what it said and when.
• No company pays for placement or sees pages before publication.

Corrections

When we find an error we fix it the same day and add a dated line to the page's update log.