Simulate radiant altitude and bearings for your location and date, estimate rates with Moon and sky brightness, peek peak ±2 nights, then confirm weather.
Frequently asked questions
Is this the same as “meteor shower tonight”?
No. Sky Events → Meteor showers answers “is anything on tonight / next peak.” This planner owns radiant geometry, by-location rates, and any-date simulation. Deep-link with ?shower=perseids&date=YYYY-MM-DD&time=02:00: the date is the evening, and a time before 07:00 is the small hours after it (Guyana time for a Guyana pin).
How accurate are the estimated rates?
The IMO formula: expected per hour = ZHR × sin(radiant height) × r^(LM − 6.5), with r the shower’s population index and LM the limiting magnitude from your site’s sky (light-pollution atlas) and the Moon’s light where you look. It assumes a clear sky; real counts scatter, so read it as “about”. Under 20° the radiant is too low to trust the number. Check Tonight score for weather.
Which nights around peak should I try?
Use the Peak ±2 night chips for the selected shower. Moon phase and work schedules often matter more than the exact peak hour, compare the hourly rate strip on each night.
Why look away from the radiant?
Meteors can appear anywhere; near the radiant, trails are short foreshortened stubs. Facing a dark wide sky 30–90° from the radiant usually shows longer streaks.
Alt/Az vs equatorial grid: which should I use?
Alt/Az matches standing outside (up from the horizon, compass directions). Equatorial shows RA/Dec lines used on star charts, helpful when comparing radiant catalog coordinates. Use Alt/Az for naked-eye spotting.
Do I need a telescope?
No. Naked-eye watching with dark adaptation works best. Use the simulator for radiant direction, then Tonight score and Dark Sky Window for weather and moonless hours.