Astronomers have found thousands of exoplanets lurking within the distant cosmos, but they know very little about their origins. Now, a dramatic new image could be offering a rare glimpse into one of the most mysterious processes in the universe: the birth of a new planet.
Using the European Southern Observatory's Very Large Telescope (ESO's VLT), researchers spotted a glowing orange spiral with a "twist" marking the spot where they believe a planet may be forming. According to a study published Wednesday in the journal Astronomy & Astrophysics, it would be the first direct evidence of a planet coming into existence.
"Thousands of exoplanets have been identified so far, but little is known about how they form," lead author Anthony Boccaletti, of the Observatoire de Paris at PSL University in France, said in a press release.
"We need to observe very young systems to really capture the moment when planets form," he said.
Astronomers observed the possible baby planet forming a spiral of dust and gas around a young star known as AB Aurigae, located 520 light years away from Earth in the constellation Auriga. Scientists know planets form as cold gas and dust collide with one another around stars over billions of years, but these new observations provide crucial data to paint a clearer picture of the process.
Researchers have been studying the star system for years using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. But until now, they have have been unable to capture clear images of this process in order to find the all-important "twist" that identifies the birth of a planet.
The deepest images of the system to date, taken using the SPHERE instrument on the VLT, show a stunning swirl around AB Aurigae, signaling the presence of a baby planet "twisting, swirling and "kicking" to create "disturbances in the disc in the form of a wave, somewhat like the wake of a boat on a lake," said co-author Emmanuel Di Folco of the Astrophysics Laboratory of Bordeaux (LAB) in France. The spiral is created as the planet rotates around the central star.
Based on predicted models, the team believes the planet is forming in the very bright yellow "twist" region close to the center of the image, which is located at about the same distance from its star as Neptune is from the sun.
"The twist is expected from some theoretical models of planet formation," said co-author Anne Dutrey, also at LAB. "It corresponds to the connection of two spirals — one winding inwards of the planet's orbit, the other expanding outwards — which join at the planet location. They allow gas and dust from the disc to accrete onto the forming planet and make it grow."
Astronomers hope to get an even clearer picture of the growing planet after the completion of ESO's Extremely Large Telescope, which will become "the world's biggest eye on the sky," in 2025.