Using the Atacama Large Millimeter/submillimeter Array (ALMA) telescope, scientists from the European Space Observatory (ESO) have captured the most detailed image of a protoplanetary disc that has ever been seen.
The image was captured from the disc around the nearby sun-like star TW Hydrae and reveals that its distance from the star is the same as that between the Earth and the sun, possibly pointing to the formation of a small planet much like our own.
TW Hydrae has been a popular focus for astronomers due to its close proximity to the Earth and the fact that it is a young star - only around 10 million years old. In addition, it has a rare face-on orientation that astronomers can see from Earth, giving them a peek of the protoplanetary disc around it in unprecedented detail.
"Previous studies with optical and radio telescopes confirm that TW Hydrae hosts a prominent disc with features that strongly suggest planets are beginning to coalesce," said Sean Andrews, lead author of the paper. "The new ALMA images show the disc in unprecedented detail, revealing a series of concentric dusty bright rings and dark gaps, including intriguing features that may indicate that a planet with an Earth-like orbit is forming there."
Other gaps discovered in the new images are around 3 to 6 billion kilometers from the central star, mirroring the average distances from the sun to Uranus and Pluto in our solar system. These gaps were also likely created from particles congregating to form planets, which cleared their orbits of dust and gas and pushed the rest of the material into bands.
Using ALMA's high-resolution, the team was also able to image faint radio emissions released from small dust grains in the disc and revealed details on the order of the distance between Earth and the sun, which is approximately 150 million kilometers. When ALMA's dishes are at maximum separation, it is able to resolve finer details not possible with other modern telescopes.
"This is the highest spatial resolution image ever of a protoplanetary disc from ALMA, and that won't be easily beaten in the future!" Andrews said.
"TW Hydrae is quite special," added David Wilner, co-author of the study. "It is the nearest known protoplanetary disc to Earth and it may closely resemble the Solar System when it was only 10 million years old."
Scientists hope to continue studying the TW Hydra disc to gain a better understanding of the evolution of Earth and the potential formation of similar planets throughout our solar system.
The draft version of the paper was released by the ESO on March 10.
