Next Pass

Glanceable countdown to the next visible ISS pass — lives in your toolbar.

Never miss the ISS overhead again. Next Pass puts the next visible International Space Station pass one click away. Pin it to your toolbar, and a live countdown is always there when you wonder "when can I see the station tonight?" — without opening a new tab, signing into an app, or unlocking your phone. WHAT IT SHOWS • Live countdown to the next visible ISS pass for your exact location • Magnitude (how bright it'll appear) with plain-English labels: very bright · bright · visible · dim · barely visible • Direction the ISS will travel across your sky (e.g. "SW → NE") • Maximum elevation in degrees (so you know whether to look high or near the horizon) • Pass duration with exact start and end times in your local timezone • Next 3 upcoming passes, each one-click addable to Google Calendar or downloadable as .ics for Outlook, Apple Calendar, Thunderbird, Proton Calendar, and others • A full-window dashboard mode for desk displays or second monitors HOW IT WORKS Pass predictions come live from the N2YO satellite-tracking service (free, you provide your own API key in Settings — 1,000 requests/hour, plenty for personal use). Your location is set once via auto-detect, address lookup, or manual coordinates. Everything stays on-device — your location, your API key, and your preferences never leave your Chrome profile. NOTIFICATIONS Optional desktop notifications fire a configurable number of minutes before each bright pass — perfect for "ten minute warning, time to grab a jacket and step outside." You can filter by minimum magnitude so you're only pinged for passes you'll actually see. PRIVACY • No accounts, no logins, no tracking • Location data is stored in your local Chrome profile only • N2YO API key is stored on-device only (never synced across devices) • The only outbound network requests are to N2YO (for pass data) and OpenStreetMap Nominatim (for optional address lookup) • Open about its sources — every data point cites where it came from Next Pass is built to grow. The current version is the free baseline. Planned additions include: • Multi-satellite tracking (Tiangong, Hubble, NOAA weather satellites, Starlink trains) with per-satellite filters and brightness preferences • A radio-comms tab with embedded ARISS amateur-radio frequency (145.800 MHz FM) and WebSDR links so you can listen to live ISS broadcasts during a pass • A launch schedule tab pulling from the Launch Library 2 API, with a toolbar badge that lights up before imminent launches • Companion mobile apps (iOS and Android) with the same widget experience plus AR sky-pointing — point your phone at the sky and an overlay shows you exactly where the station is, with its full predicted trajectory drawn on the live camera feed • Optional premium tiers for SMS notifications and integration with smart telescopes (ASCOM Alpaca, INDI, Unistellar, Vaonis, Seestar, and direct LX200/SynScan over Web Serial) so a connected scope can auto-point at the rise coordinates a minute before each pass The free core — toolbar countdown, dashboard, .ics export, browser notifications — will stay free. Need a free N2YO API key? Register at https://www.n2yo.com/login/register/ (takes about 30 seconds, no credit card). Found a bug or have a feature request? [add support email / GitHub URL here before submission] Privacy policy URL (required by Chrome Web Store for extensions that handle user data) [https://dan-lee-odinson.github.io/next-pass-privacy/] COMPATIBILITY Chrome, Edge, Brave, Arc, Opera, Vivaldi, and any other modern Chromium-based browser. Works on Windows, macOS, ChromeOS, and Linux. Light on resources — the service worker stays dormant between alarms. ACKNOWLEDGMENTS Pass prediction data comes from the N2YO satellite-tracking service. Geocoding comes from OpenStreetMap contributors under the ODbL. The ISS is operated by NASA, Roscosmos, JAXA, ESA, and CSA — built across two decades by people from over a dozen countries. Next Pass is an independent project not affiliated with any space agency. We are simply grateful they put it up there. Install Next Pass and start watching. Once you've seen it streak silently across your sky, you will not forget.