Van Gogh's night sky is a field of roiling energy.

Below the exploding stars, the village is a place of quiet order.

Connecting earth and sky is the flamelike cypress...

...a tree traditionally associated with graveyards and mourning.

But death was not ominous for van Gogh. "Looking at the stars always makes me dream," he said, "Why, I ask myself, shouldn't the shining dots of the sky be as accessible as the black dots on the map of France?"

Just as we take the train to get to Tarascon or Rouen, we take death to reach a star."

The artist wrote of his experience to his brother Theo: "This morning I saw the country from my window a long time before sunrise, with nothing but the morning star, which looked very big." This morning star, or Venus, may be the large white star just left of center in The Starry Night.

The hamlet, on the other hand, is invented, and the church spire evokes van Gogh's native land, the Netherlands. The painting, like its daytime companion, The Olive Trees, is rooted in imagination and memory.

Leaving behind the Impressionist doctrine of truth to nature in favor of restless feeling and intense color, as in this highly charged picture, van Gogh made his work a touchstone for all subsequent Expressionist painting.

Mystery abounds in some museums. The history of some objects is shrouded and obscured. Scroll on to ponder the secrets of some of the world's most mysterious artefacts.

Found in Gough’s Cave in Cheddar Gorge, this rather gory object dates back around 14,700 years. Thought to have been used in rituals by the ancient tribes of Somerset, it may well indicate that these early people had a penchant for human flesh. In fact, some scientists believe that the find shows evidence of cannibalism. 

Since the first of these mysterious dodecahedrons was discovered in England around 300 years ago, almost 100 have been found in various locations across Europe. So far, scientists and archaeologists are baffled as to what these 12-sided objects were used for. While some believe they were made as toys for children, others think they were weapons used by the Roman army to conquer their foes. 

Sometimes, the absence of an object can be just as mysterious as its presence. The Isabella Stewart Gardner Museum in Boston displays a row of empty frames. These show where a number of masterpieces once hung, before they were stolen in an art heist in 1990.  

During the theft, two robbers dressed as policemen walked into the museum, removed 13 works by artists such as Rembrandt, Vermeer, Manet and Degas, and walked out. It’s estimated that the collective value of the stolen art is more than $500 million. To this day, the theft remains unsolved and the location of the artworks unknown.

Recovered in 1900 from the wreck of a Roman cargo ship that sank near the Greek island of Antikythera, the Antikythera Mechanism might possibly be the world’s earliest known analogue computer. Estimated to have been built in the late 2nd century BCE it was probably used to track the paths of the sun, moon and planets. However, because some key parts are missing, we may never know what its exact function was. 

These intricately carved chess pieces were found on the Isle of Lewis, Scotland in 1831. The pieces are thought to have been made in Norway around 1,000 years ago. How they ended up in Scotland is still a mystery. 

However, as the Western Isles were once part of Norway, it’s possible that they were brought to the island by a Norwegian merchant. As well as having intriguing origins, the Lewis Chessmen are the only surviving medieval chess set in the world.

These beautiful but mysterious objects were uncovered in Costa Rica when the United Fruit Company began clearing land. Thought to date back to between 700 CE and 1530 CE, experts have no idea what these perfect stone spheres were for or why they were made. However, considering the amount of work that went into each piece, we can be fairly sure they were for something important.