Privacy

What never leaves your browser

The tracker is a static page with no application server behind it. Every calculation runs locally. The following are held in your browser's own storage on your device, are readable only by this site, and are never transmitted anywhere:

• The observer location you type in or pick on the map, including any coordinates obtained from your browser's location permission.
• Your selected satellites and saved configuration.
• Cached orbital data downloaded from Celestrak, kept for about a day so the app works offline and does not re-download constantly.
• If you use the optional Copernicus feature, your ESA username and the access tokens ESA issued. Your ESA password is never stored, anywhere.

Clearing site data for this domain in your browser settings erases all of it. The operator of this site cannot see any of it and has no way to retrieve it.

Cookies

This site sets no cookies of its own and there is no consent banner because there is nothing to consent to. The data described above uses your browser's local storage, which is not sent with requests the way cookies are.

One exception is worth naming: if you open the feedback form, it loads Cloudflare Turnstile to check you are not a bot, and that service may set its own cookie for that purpose. It only loads if you open the form.

What the hosting provider sees

The site is hosted on Cloudflare Pages. Like any web host, Cloudflare processes the requests your browser makes in order to serve the page, and produces aggregate traffic statistics from them — request counts, rough visitor counts by IP address, and country.

These are standard server-side hosting logs and aggregate figures. No analytics or measurement script is served to your browser, there is no tracking pixel, and no profile of you is built or shared. Cloudflare's own handling of that data is governed by its privacy policy.

If you send feedback

The feedback form is the only part of the site that sends anything to a server. Using it is entirely optional. When you submit it, this is everything that is recorded:

• Your message, and the topic you chose.
• Your email address, only if you choose to provide one. The field is optional and exists solely so a reply is possible. Leave it blank and the message is anonymous.
• Your country, as determined by the hosting provider from the connection — the country only, not a finer location.
• Your browser's User-Agent string, capped at 200 characters. This is the standard identifier every browser sends with every request — for example Mozilla/5.0 (Windows NT 10.0; Win64; x64) … Chrome/129.0.0.0 — and it is kept to help reproduce reported bugs. In practice a User-Agent is well under 200 characters, so the cap is a size limit rather than a privacy measure, and it is recorded essentially in full.

Your IP address is not stored. It is used in the moment to calculate a salted, one-way hash that enforces a sixty-second limit between submissions, and that hash expires within a minute. The address itself is never written down.

Messages are kept for one year and then deleted automatically. They are stored in Cloudflare's key-value storage, readable only by the operator, and are not shared with anyone, not sold, and not used for anything except answering and improving the site.

The form is protected by Cloudflare Turnstile, a privacy-focused bot check that does not use behavioural tracking or advertising profiles.

Other services your browser contacts

Because everything runs client-side, your browser makes these requests directly. Each one inherently reveals your IP address to that service, exactly as visiting any website does. None of them receive your observer location or anything you have entered.

• Celestrak — to download orbital element sets. Happens automatically when you load satellite data.
• unpkg.com — to load the two open-source libraries the app uses.
• ESA Copernicus Data Space — only if you use the optional precise-orbit feature. Your ESA credentials go directly to ESA, never to this site; see the about page for the detail.
• Cloudflare Turnstile — only if you open the feedback form.

Where this is operated

This site is run by an individual in the United States, and is hosted on Cloudflare's global network. Feedback messages, if you send any, are stored in Cloudflare's key-value storage.

Children

The site is not directed at children and knowingly collects nothing from anyone. It asks for no personal information at all beyond the optional email address on the feedback form.

Your choices

• Don't want anything recorded at all? Simply don't use the feedback form. Using the tracker itself sends nothing.
• Want your locally stored data gone? Clear site data for this domain in your browser settings.
• Sent feedback and want it deleted, or want to know what was kept? Email the address below and it will be removed.

Contact and changes

Privacy questions, deletion requests, or anything else: [email protected]

If this policy changes, the date below changes with it. There is no mailing list to notify, because there is no mailing list.

Last updated 21 September 2026.

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