What Are the Colors of the Northern Lights? An Iceland Guide
Look up during a good Northern Lights display in Iceland and the first color you will usually notice is green. On stronger or more complex nights, you may also see red above the green arc, purple or blue along its lower edge, or flashes of pink where several emissions overlap.
These colors are not filters painted across the sky. They are light released when energetic particles excite gases high in Earth’s atmosphere. The color depends mainly on:
which atmospheric gas is excited;
the altitude of the collision;
the energy of the incoming particles;
how long the excited atom or molecule can hold that energy before another collision interrupts it;
and whether you are looking with your eyes or through a camera.
Here is the practical guide to what those colors mean—and what Northern Lights travellers are most likely to see in Iceland.
Why do the Northern Lights have different colors?
Auroras begin when charged particles are guided by Earth’s magnetic field into the upper atmosphere near the polar regions. Collisions transfer energy to atoms and molecules, especially atomic oxygen and molecular nitrogen. When those particles return toward their normal energy state, they release photons: packets of light at particular wavelengths.
Different atmospheric particles have different allowed energy transitions, so they do not all produce the same color. Altitude matters because the atmosphere becomes thinner as you go higher. In thinner air, an excited atom can sometimes remain undisturbed long enough to produce an emission that would be interrupted by collisions lower down.
The result is a natural layer cake of color.
Green Northern Lights: the most common color in Iceland
Green is the color most people associate with the Northern Lights, and it is normally the most common visible aurora color in Iceland.
The familiar green glow comes mainly from excited atomic oxygen emitting light at a wavelength of about 557.7 nanometres. It is commonly produced in the lower thermosphere, roughly around 100–150 kilometres above Earth, although an aurora is not a perfectly tidy sheet at one fixed height.
Green dominates for two useful reasons: this oxygen emission is often strong, and human night vision is relatively sensitive around the green part of the spectrum. That makes a bright green arc or curtain easier for our eyes to detect than some weaker red or blue emissions.
Iceland does not contain a special kind of aurora-producing oxygen. Its advantage is location: Iceland sits at high latitude beneath or near the region where auroral activity commonly occurs. Green is also the most familiar aurora color across other high-latitude destinations.
Red Northern Lights: oxygen higher in the atmosphere
Red aurora can also come from atomic oxygen, but through a different energy transition. The best-known red oxygen emission is near 630.0 nanometres and is generally produced higher than the bright green layer, often above roughly 200 kilometres.
At those heights the air is very thin. That matters because the red transition is slow: an excited oxygen atom needs time to release its red photon. In denser air lower down, another collision is more likely to interrupt—or “quench”—that emission before it appears.
This is why red can sit above a green auroral curtain. It may appear as a red cap, a diffuse glow or the upper portion of tall rays. Red aurora is usually less obvious to the naked eye than vivid green, but strong displays can make it unmistakable.
Red aurora is sometimes reported far south during major geomagnetic storms because observers at lower latitudes may be looking toward the high-altitude top of an expanded auroral display. That does not mean red belongs only to lower latitudes. Red can also be seen from Iceland when the geometry, activity and brightness cooperate.
Blue and purple Northern Lights: nitrogen at lower altitudes
Blue, violet and purple tones are associated mainly with emissions from molecular nitrogen and ionized molecular nitrogen. They are often found lower in the auroral structure, where more energetic particles penetrate deeper into the atmosphere.
To an observer or camera, these colors may form a narrow blue-purple fringe along the bottom edge of a green curtain. Purple can also appear where blue nitrogen emissions overlap visually with red and green light.
Pure blue is harder for the dark-adapted human eye to see clearly. Cameras often record it more strongly, particularly when the aurora is moving quickly or the exposure gathers light that looked faint in real time.
Pink and magenta Northern Lights: colors working together
Pink is real, but it is not usually explained by one simple “pink gas.” It often appears when red and blue or violet emissions from nitrogen mix with the brighter green oxygen layer in the same part of the display or along the same line of sight.
Pink or magenta can show up along the energetic lower edge of a bright curtain. During fast, intense movement, a camera may catch a striking pink border that was much subtler to the eye.
Yellow, orange and white aurora
Yellow and orange-looking auroras are often blended colors rather than a separate dominant auroral emission. Green and red light can overlap to look yellowish or orange, while atmospheric conditions, camera processing and white balance can shift the recorded color.
White or pale grey aurora is also common to human vision. A faint aurora can look like a colourless cloud or a milky band because our eyes rely more on low-light-sensitive rod cells at night. Rod cells are excellent at detecting dim light and motion but poor at distinguishing color.
A photograph of the same arc may appear clearly green because the camera collects light over time and records color differently from the human visual system. If a very bright part of a photograph looks white, it may also be overexposed or contain several colors blended together.
Northern Lights color guide
Green — mainly atomic oxygen at 557.7 nm, commonly around 100–150 km. This is the most common and usually easiest aurora color to see in Iceland.
Red — mainly atomic oxygen at 630.0 nm, generally higher and often above about 200 km. It may form a red top or diffuse glow.
Blue or violet — mainly molecular nitrogen and ionized molecular nitrogen, often toward the lower, more energetic edge. Cameras may reveal it more clearly than your eyes.
Pink or magenta — often overlapping nitrogen and oxygen emissions along the lower border of bright curtains.
Yellow or orange — usually overlapping emissions and color mixing; photographs should be interpreted with care.
White or grey — often the result of low-light human vision, blended light or camera saturation.
The altitude ranges are approximate. Aurora altitude, energy and chemistry form a continuum, and a single display can contain several emitting layers at once.
Why does the camera show more color than your eyes?
Guests sometimes look at the back of a camera and ask the obvious question: “Why is it greener in the photo?”
The camera is not necessarily inventing the aurora. It can collect photons for longer than your eye does in one instant, and its sensor retains color information that human night vision handles poorly. Phone processing can then increase saturation, contrast and brightness.
Your eyes also adapt during the evening. A weak arc may begin as a pale shape. If it strengthens, develops rays or starts moving, green can become obvious and other colors may emerge. Bright aurora can look richly colored without a camera; faint aurora often will not.
This is also why two honest photographs of the same display can look different. Exposure time, aperture, sensor, white balance, editing and screen settings all affect the result.
Does color tell you how strong the aurora is?
Not by itself.
A bright, fast green display can be spectacular without obvious red or purple. A camera can record red that was barely visible to the eye. Different colors tell us something about the emitting gas, altitude and particle energy, but they are not a simple scoreboard where more colors automatically mean a better experience.
Cloud cover, darkness and your location still decide whether you can see the sky at all. Our Northern Lights forecast for Iceland explains why a high aurora number cannot compensate for thick clouds.
What color are you most likely to see in Iceland?
Green is the honest answer.
On many nights, the first visible structure is a pale or green arc. As activity develops, it may break into green rays and curtains. Red above the curtain, or purple and pink along its lower edge, is a bonus—not something any guide can promise in advance.
That uncertainty is part of the appeal. Every display is its own combination of particle energy, atmospheric height, movement, brightness and viewing conditions.
If you would like help finding clear skies—and professional photos that preserve the colors of the night—see our small-group Northern Lights tour from Reykjavík. We operate the hunt based on the conditions of the evening rather than driving to one fixed viewing location.
Quick questions about Northern Lights colors
What is the rarest Northern Lights color?
There is no universal rarity ranking for every observer and every display. Pure-looking blue and strong red are generally seen less often than green, while yellow and orange appearances are often mixtures. Location, intensity, altitude, eyesight and camera settings all affect what gets reported.
Can the Northern Lights be red in Iceland?
Yes. High-altitude oxygen can produce red aurora over Iceland. Red can appear above green curtains or as a more diffuse glow. It is usually less common and often fainter to human vision than green.
Are purple Northern Lights real?
Yes. Blue and violet nitrogen emissions can contribute to a purple lower edge, sometimes mixed with red and green emissions. A camera may show that purple more strongly than your eyes did.
Why did the Northern Lights look grey to me?
Human color vision weakens in low light. A faint aurora may therefore look white or grey even when a longer camera exposure records green. Movement, rays and structure can help distinguish faint aurora from ordinary cloud.
Do different countries get different aurora colors?
The same atmospheric physics applies everywhere. What changes is the observer’s position relative to the auroral oval, the altitude and energy of the display, viewing geometry, darkness and weather. Iceland commonly sees green because it is a high-latitude aurora destination—not because Icelandic air contains different ingredients.
Sources and further reading
Science sources checked 19 September 2026. Altitudes are approximate because auroral emissions occur across ranges rather than at perfectly fixed boundaries.
Planning a guided aurora hunt
If photography is part of your trip, compare whether your tour includes delivered aurora photos. Our Northern Lights tour comparison brings together dated reviews, tour formats and inclusions to help you choose.
Comments