Nova Vulpeculae 1670

By Kathy Fey

A mystery explosion in the night sky turns out to have been caused by colliding stars.

One of history’s mysteries revolved around a strange explosion observed in the sky in 1670, long thought to have been the first nova on record. Recent research suggests that this enigmatic event was actually a rare stellar collision.

According to a report by Astronomy Magazine, the so-called Nova Vulpeculae of 1670 was more likely the collision of two stars, which shines brighter than a nova but not as brightly as a supernova.

Observations made with various telescopes including the Submillimeter Array, the Effelsburg radio telescope and APEX have revealed the more unusual nature of the light source – a violent collision.

When the event first occurred, it would have been visible from Earth with the naked eye. Now, submillimeter telescopes are needed to detect the traces left in the aftermath of the event.

When first observed, 17^th century astronomers described what they saw as a new star appearing in the head of Cygnus, the swan constellation.

“For many years, this object was thought to be a nova, but the more it was studied, the less it looked like an ordinary nova, or indeed any other kind of exploding star,” said Tomasz Kaminski of the European Southern Observatory.

Having observed the area of the supposed nova with both submillimeter and radio wavelengths, scientists “have found that the surroundings of the remnant are bathed in a cool gas rich in molecules with a very unusual chemical composition,” said Kaminski.

Researchers concluded that the amount of cool material they observed was too much to have been produced by a nova. The nature of the gas debris best fit with the rare scenario of two stars merging in an explosive collision.

The team’s report was published in the journal Nature.

Karl Menten of the Max Planck Institute called the discovery “the most fun – something that is completely unexpected.”