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Grimm Reaper Photography, Whyalla (2026)

25/02/2026

Quick drive to Point Lowley & Fitzgerald Bay just out of Whyalla SA last week. So serene out there :)

16/08/2025

That “meteor colour chart” meme floating around the internet (the one that claims blue meteors are magnesium, green are nickel, orange are sodium, etc.) is misleading and oversimplified. Meteors don’t behave like neat flame tests in a lab. Their colours are much more complex and depend on several overlapping factors.

Plasma Emission from Ionized Air (Primary Cause) - When a meteoroid slams into the atmosphere at tens of km/s, it compresses and heats the air in front of it. The air becomes ionized plasma, which glows at specific wavelengths. The dominant emission is often green from excited atomic oxygen (similar to auroras), especially around ~90–120 km altitude. This is why bright green fireballs are so common.

Meteor Speed and Energy - Faster meteors (e.g., Leonids at ~70 km/s) reach higher temperatures, exciting different atmospheric molecules. The temperature affects which wavelengths dominate. Cooler meteors may glow reddish or yellowish; hotter ones often look bluish-green or pure white.

Fragmentation & Density - If the meteoroid breaks apart violently, the sudden burst of plasma can briefly shift colours. Denser, slower meteors may glow more orange-red.

Metallic Emission from the Meteoroid (Secondary Role) - Some vaporized meteoroid atoms do emit light. Sodium → strong orange/yellow line. Magnesium → greenish-white. Iron → bluish-white. But this is mixed with atmospheric glow and plasma radiation, so the colours can’t be matched 1:1 to composition like the viral graphic suggests.

Why Green is Most Common - Oxygen emissions (557.7 nm green line) dominate in the upper atmosphere. The human eye is also most sensitive to green light in the dark, so even when the spectrum is mixed, we often perceive meteors as green. Sodium (orange-yellow) also contributes, but usually only in bursts or flares.

In short: Meteor colour is a combination of atmospheric chemistry, plasma physics, meteoroid speed, and human eye sensitivity — not just the rock’s chemical makeup.