Privacy
1The short version
CME Tracker is a free, no-account science site. It collects almost nothing, and nothing it collects identifies you.
- No cookies. Not one. A few preferences live in your browser's local storage and never leave it (except the anonymous id below).
- No ads, no third-party trackers, no analytics SDKs, no fingerprinting, no cross-site anything.
- No accounts. The only personal data we ever hold is an email address you explicitly give us, for the mailing list or a feedback reply, and you can remove it in one click or one message.
- Nothing is sold or shared with anyone, for any reason.
2Usage analytics: what we collect
To know whether anyone uses the site and which features matter, we record lightweight usage events in our own database (no third-party analytics service). Each event contains, at most:
- A random anonymous id: a random string generated in your browser and kept in its local storage. It is not derived from you or your device; it just lets us count "one visitor" instead of "one pageview" and tells us nothing about who you are.
- The page path you viewed (e.g.
/help) and, for feature events, a short name likelayer:spacecraft. - The referrer your browser reports (which site linked here), if any.
- Device class: literally the word
mobileordesktop. - A coarse country code (e.g.
US), read from our host's edge header. We never see, store, or log your IP address in our database.
A small "online now" heartbeat keeps one row per visitor while a tab is open; those rows are deleted within a day. Usage events are deleted after 180 days.
3The mailing list
If you join the list, we store your email address and when you subscribed, nothing else. Emails are occasional (storm alerts, notable events, new features). Every email carries a one-click unsubscribe link and the standard one-click-unsubscribe headers; unsubscribing takes effect immediately, and an unsubscribed address is never silently re-activated. We add no tracking pixels to our emails.
Delivery is handled by Resend, which processes your address solely to deliver our mail.
4Feedback
The feedback form stores your message, an optional role (educator, student, …), an optional email if you'd like a reply, and the same coarse country code. It's read by one human (the site's author) and used for nothing else.
5What lives in your browser
Local storage and one session flag, no cookies. You can clear all of it any time via your browser's site-data settings, and the site keeps working. None of it is sent to us except the anonymous id in the first row.
If you install the site as an app, your browser keeps its name and icon. The site caches no pages or data for the app. It keeps one flag for the session so an app launch is counted once (last row).
| Key | What it is |
|---|---|
cme_vid | The random anonymous analytics id described above. |
cme_subscribed, cme_join, cme_welcome | Flags so we don't re-show signup/welcome prompts you've already seen. |
cme_coach, cme_rail_ask | Flags that you have seen the first-visit tour, or dismissed the email prompt in the tracker's side panel. |
cme_learn, cme_learn_call, cme_learn_name | Your course progress, your answers and live call, and the name you typed for the completion card. None of it is sent to us. |
tz, panel-left, panel-right | Display preferences (timezone, collapsed panels). |
cme_setup, cme_viz, cme_fluid_mode | Your tracker setup: which layers, view and filters you left on, the map's look, and whether the fluid layer shows speed or density. |
cme_play_best | Your best score in the game. |
cme_cache | A short-lived copy of public space-weather data so reloads are fast. |
cme_app_open | Session only, and only in the installed app: a flag so one launch is counted once. It is gone when the app closes. |
6Embeds & the public API
Other sites can embed our live widgets (iframes) and query our public JSON API. Those requests get the same treatment as a normal visit: no cookies, and at most the anonymous analytics event above. Widget click-throughs are tagged with the hosting site's domain so we can thank sites that embed us. That tag identifies the site, not you.
7Your choices
- Leave the mailing list: click unsubscribe in any email. Done immediately.
- Reset analytics: clear this site's data in your browser; a new random id is generated and the old one orphans (and its events age out within 180 days).
This site is usable in full without giving us anything at all.
8Changes
If our practices change, this page changes with them, and the "effective" date below moves. Effective: 8 October 2026.