Build a Raspberry Pi All-Sky Camera for Meteor and Aurora Detection

This site's astrophotography content covers pointing a Pi HQ Camera at specific targets — planets, the moon, tracked long exposures. An all-sky camera does the opposite: a fisheye lens staring straight up, running all night, every night, capturing the entire sky at once. It's not for pretty pictures — the fisheye distortion makes sure of that — it's for catching the things you'd otherwise miss by not looking: meteors, aurora activity, satellite flares, and the occasional fireball bright enough to make local news. This project builds a weatherproof, always-on all-sky station using the free, open-source RMS (Raspberry Pi Meteor Station) software, the same software behind the Global Meteor Network's citizen-science camera network.

Why RMS Software and Not a Simple Timelapse Script

A basic intervalometer script capturing one frame every few seconds will catch meteors by luck, but RMS is purpose-built for this: it runs continuous low-light video capture, automatically detects moving points of light against the star field in real time, cross-references detections against known satellite and aircraft tracks to filter them out, and if you register your station with the Global Meteor Network, calculates real orbital trajectories by triangulating with other nearby stations. Running RMS instead of a DIY script turns a neat nightly photo project into a station that contributes real astronomical data.

Lens Choice: Fisheye Focal Length Trade-off

LensField of viewTrade-off 1.55mm M12 fisheye~190° (full hemisphere, with some distortion loss at the horizon)Catches almost everything overhead; dimmer meteors and stars are smaller and harder to detect reliably 2.97mm M12 fisheye~115°Better sensitivity and detection reliability per star; sky coverage limited enough that multiple cameras would be needed for a full dome

For a single-camera backyard station, the 1.55mm is the common choice — full-sky coverage matters more than per-pixel sensitivity when you're just trying to catch whatever happens, anywhere overhead, on any given night.

Building the Weatherproof Housing

• Dome orientation matters. Acrylic domes have a molded seam; mount the camera so the seam runs north-south rather than directly over the lens, where it would show up as a faint line in every frame.
• Anti-dew heating is not optional in most climates. A cold clear night is exactly when condensation forms on the dome's exterior, and exactly when you want the clearest view — a low-wattage heater strip around the dome's base keeps it a few degrees above ambient, enough to prevent dew without meaningfully heating the camera sensor.
• Seal every cable entry with a proper cable gland or a generous bead of outdoor silicone — a junction box that's watertight except for a single unsealed USB passthrough is not watertight.
• Desiccant packets inside the housing, replaced or recharged every few months, control the residual humidity that gets in during installation and through minor temperature-driven pressure changes.
• Power over Ethernet avoids running a separate weatherproof power cable alongside the data cable, and lets the Pi sit well away from the house on a pole or eave mount without a nearby outlet.

Software Setup

Install RMS from the official repository on Raspberry Pi OS, run the guided configuration to set your station's latitude/longitude and camera parameters, and run the built-in star-based lens calibration — RMS needs an accurate astrometric calibration (matching detected stars to their catalog positions) to turn pixel coordinates into real sky coordinates. The software runs a nightly capture-and-detect cycle automatically once configured: capturing through the night, running detection in the morning, and optionally uploading confirmed meteor detections to the Global Meteor Network if you choose to register the station.

Realistic Expectations

A single backyard station in a light-polluted area will miss plenty of faint meteors that a dark-sky station would catch, and won't reliably image aurora unless you're at a latitude where aurora is visible with the naked eye in the first place. What it will reliably do: catch bright fireballs, provide usable (if occasional) aurora captures during actual geomagnetic storms, log satellite passes and flares, and build a genuinely interesting all-night archive that occasionally produces something worth sharing — a fireball frame, a surprise aurora glow, or a meteor shower's actual radiant point plotted from a week of detections.

Between the weatherproofing and the astrometric calibration, this is a more involved build than most Pi camera projects on this site, but it's also one of the few that runs completely unattended for months at a time and still occasionally produces a genuinely rare capture. Budget real time for dialing in the dome seal and the lens calibration before trusting it to run through an entire meteor shower unattended.