The 2026 Perseid meteor-shower forecast places the main maximum near solar longitude 140.0°–140.1°.
Solar longitude measures Earth’s position in its orbit using the apparent ecliptic longitude of the Sun. It provides a consistent astronomical reference for comparing meteor-shower activity from year to year, regardless of calendar dates and time zones.
The Perseid maximum occurs when Earth reaches the densest portion of the debris stream left by Comet 109P/Swift–Tuttle. Forecasts express this position as a solar longitude because the shower’s peak can occur at different clock times in different years.
This value should not be confused with the radiant’s right ascension or declination. Those coordinates describe where the meteors appear to originate in the sky, while solar longitude describes Earth’s orbital location during the encounter.