The sun dog phenomenon observed over Stockholm and depicted in the famous painting Vädersolstavlan.

Understanding Sun Dogs: A Celestial Spectacle

Often captivating observers with their ethereal beauty, a sun dog—sometimes called a sundog or a mock sun—is a fascinating atmospheric optical phenomenon. In meteorological terms, it's more formally known as a parhelion (with its plural form being parhelia). This visual marvel typically manifests as one or two bright, often subtly colored, patches of light appearing to the side of the Sun itself. These luminous spots frequently flank the Sun, usually positioned within a larger, circular optical effect known as a 22° halo.

As a distinguished member of the wider family of atmospheric halos, sun dogs owe their existence to the intricate dance between sunlight and minuscule ice crystals suspended within the Earth's atmosphere. Specifically, these are typically hexagonal plate-like ice crystals, which act like tiny prisms, refracting the sunlight as it passes through them. For sun dogs to appear, these ice crystals must be predominantly aligned horizontally as they flutter downwards. The precise angle of refraction from these crystals, particularly when the Sun is low in the sky, channels the light towards our eyes, creating the illusion of secondary suns.

You'll typically spot sun dogs as a symmetrical pair of bright, often iridescent patches of light, situated approximately 22 degrees to the left and right of the actual Sun. Crucially, they appear at the exact same altitude above the horizon as the Sun itself, creating a striking horizontal alignment. While they can grace skies anywhere across the globe and during any season, their visibility and brilliance can vary significantly. They are most pronounced and easily observed when the Sun is low in the sky, either shortly after sunrise or before sunset, as the angle of light passing through the ice crystals is optimal for their formation and perception.

Vädersolstavlan: A Window into History and Art

Beyond being a mere painting, Vädersolstavlan (pronounced approximately "VEH-der-sohl-stah-vlan"), a Swedish term meaning 'The Sundog Painting', is a profoundly significant oil-on-panel artwork. It vividly depicts a remarkable atmospheric optical phenomenon, specifically a halo display, that graced the skies over Stockholm on 20 April 1535. The painting takes its name from the prominent sun dogs (or vädersol in Swedish, literally 'weather sun') that are clearly visible in its upper right section, drawing attention to this celestial event.

This masterpiece holds a unique place in cultural and artistic history for several compelling reasons. It is widely acknowledged as the oldest known depiction of Stockholm rendered in colour, offering an invaluable glimpse into the city's appearance in the early 16th century. Furthermore, it is arguably the earliest surviving Swedish landscape painting and, significantly for meteorologists and art historians alike, the oldest visual record of sun dogs known to exist. Its detailed portrayal of such a complex atmospheric phenomenon makes it a rare and precious document.

The Mystery of the Original and the Enduring Copy

The original painting, believed to have been created shortly after the 1535 event and traditionally attributed to an artist known only as Urban Målare ("Urban [the] Painter"), has unfortunately been lost to time. Very little verifiable information about this initial version or its creator survives. However, its legacy lives on through a meticulously crafted copy from 1636, executed by the artist Jacob Heinrich Elbfas. This invaluable copy is preserved within Storkyrkan (the Great Church) in Stockholm, serving as a primary historical and artistic record.

For many years, this 1636 copy was mistakenly believed to be the original painting that had merely undergone restoration. Its true nature as a copy only became clear following a comprehensive and delicate restoration project undertaken between 1998 and 1999. Prior to this intervention, the painting was obscured by thick layers of brownish varnish, rendering its intricate details and vibrant colours barely discernible. The painstaking restoration effort not only clarified its status but also revealed the painting's original clarity and detail, allowing historians and the public to truly appreciate its significance.

A Canvas Woven with Swedish History and Controversy

The creation of Vädersolstavlan occurred during a pivotal and turbulent epoch in Swedish history. The mid-16th century marked the very establishment of modern Sweden as a sovereign nation, a period inextricably linked with profound religious and political transformations. This era saw the widespread introduction of Protestantism, leading to Sweden's dramatic break from the Catholic Church and, concurrently, its final severance from the Kalmar Union, which had previously bound it with Denmark and Norway.

Intriguingly, the painting was commissioned by Olaus Petri, a towering figure of the Swedish Reformation. Petri, an influential clergyman and scholar, was instrumental in shaping the new Protestant church in Sweden. However, the interpretation and implications of the celestial event depicted in the painting, particularly in such a religiously charged and politically volatile atmosphere, led to significant controversies. These tensions arose between Petri and King Gustav Vasa, the founder of modern Sweden, whose authority and vision for the new nation were absolute. The exact nature of these disagreements and their historical context were carefully guarded secrets for centuries, adding a layer of mystery and intrigue to the painting's narrative. Such an event, a "mock sun," could be interpreted in various ways—as a divine omen, a warning, or a sign of approval—each carrying potent political and religious weight in a society steeped in belief.

In the 20th century, Vädersolstavlan transcended its role as a historical artifact to become a powerful icon representing the rich and complex history of Stockholm. It is now frequently showcased and celebrated whenever the city's past is commemorated, standing as a silent, yet eloquent, witness to centuries of Swedish development and the enduring human fascination with the heavens.

Frequently Asked Questions about Sun Dogs and Vädersolstavlan

What is a sun dog?
A sun dog, also known as a mock sun or parhelion, is a common atmospheric optical phenomenon. It appears as a bright spot of light to one or both sides of the Sun, often subtly colored, and is caused by the refraction of sunlight through horizontally aligned ice crystals in the atmosphere.
How do sun dogs form?
Sun dogs form when sunlight passes through plate-shaped hexagonal ice crystals suspended in the air. These crystals act like prisms, bending the light. For a sun dog to be visible, these ice crystals must be predominantly aligned horizontally as they fall through the atmosphere.
Where and when are sun dogs best seen?
Sun dogs can be observed anywhere in the world, during any season. However, they are most vivid and conspicuous when the Sun is low in the sky, typically shortly after sunrise or before sunset, as the angle of the light passing through the ice crystals is optimal at these times.
What is Vädersolstavlan?
Vädersolstavlan, meaning 'The Sundog Painting' in Swedish, is an important oil-on-panel painting from 1636 (a copy of a lost original from 1535). It depicts a halo display, including prominent sun dogs, observed over Stockholm on April 20, 1535.
Why is Vädersolstavlan historically significant?
It holds immense historical and cultural value as arguably the oldest depiction of Stockholm in colour, the oldest known Swedish landscape painting, and the oldest visual record of sun dogs. It also provides a unique lens into a critical period of Swedish history, specifically the establishment of modern Sweden and the Reformation.
Is the original Vädersolstavlan painting still in existence?
No, the original painting from 1535, attributed to Urban Målare, has been lost. The painting displayed today in Storkyrkan, Stockholm, is a highly regarded and accurate copy made in 1636 by Jacob Heinrich Elbfas.
Who commissioned Vädersolstavlan, and why was it controversial?
The original painting was commissioned by Olaus Petri, a key figure in the Swedish Reformation. Its depiction of a celestial omen, in a politically and religiously charged era, led to controversies between Petri and King Gustav Vasa. The exact nature of these disputes, possibly related to interpretations of the event's divine meaning, remained a closely guarded secret for centuries.