This is a free site with no accounts, no sign-up and nothing for sale. These terms are short because there is little to agree to. Using the site means accepting them.
Who runs this
Samu Leino, Finland. Contact: hello@unseencosmos.com.
The writing
The text on the pages is written here and is protected by copyright. You may quote it with attribution, as you would any source. You may not republish whole pages.
Every page names the sources it draws on. Those works belong to their own authors and publishers, and nothing here grants any right to them.
The illustrations
The illustrations are published under CC BY-NC 4.0. What that allows is set out on the illustrations page.
What is promised about accuracy
Pages say what the named sources say, and where measurements disagree the pages try to say so. Astronomy changes as new observations arrive, and mistakes are still possible. Nothing here is advice of any kind. If something is wrong, write and it will be corrected.
What is not promised
The site is provided as it is. There is no guarantee that it will be available, free of errors, or stay in its current form. It can change or stop without notice.
Links out
Pages link to space agencies, observatories, archives, journals and encyclopedias. Those sites are run by other people under their own terms, and linking to them is not an endorsement of anything on them.
Doing harm to the site
Do not attempt to break the site, overload it, or harvest it automatically at a rate that affects other readers. Ordinary reading, linking, quoting and classroom use are exactly what it is for.
Privacy
What is collected and what is not is described on the privacy page.
Changes
These terms can change. The date at the top is how you can tell.
Which law applies
Finnish law applies, and disputes belong to the courts of Finland. If you are a consumer resident elsewhere in the European Union, this does not remove the protections of the mandatory consumer law of your own country.