Astronomers using the James Webb Space Telescope (JWST) made a surprising discovery: They were able to see a third world being formed around the infant star PDS 70, some 400 light-years far away from Earth. The MIRI mid-infrared Disk Survey (MINDS) project recorded the formation of the “third world.”
Using JWST’s Near Infrared Camera (NIRCam), the scientists also observed a massive spiral stream of material that was accelerating the formation of an already discovered planet, PDS 70C.
“We found new evidence for the presence of a third planet in the system”
PDS 70C, a large planet, is surrounded by its disk of material, and the spiral stream is feeding it as well, resulting in the formation of its moons.
Valentin Christiaens, a MINDS team member and postdoctoral researcher at KU Leuven and the University of Liege, told Space.com “We found new evidence for the presence of a third planet in the system, which was proposed based on VLT observations.”
“Furthermore, the new infrared measurements we obtained for the two known protoplanets suggest the presence of heated material around them — which may be the building blocks for moons forming around them,” he said.
Astronomers studied the PDS 70 system using a variety of telescopes, including the ground-based Atacama Large Millimeter/submillimeter Array (ALMA) and the Very Large Telescope.
Astronomers have been attracted by the system since the protostar and its protoplanetary disk are likely less than 5.5 million years old.
“PDS 70 is special, as it is the only protoplanetary disk so far where all astronomers agree that we have found forming planets caught in the act,” said Christiaens.
“Detailed study of this system has thus allowed us to learn a lot about planet formation,” he added.
The researchers need to gain more knowledge of the potential third planet’s attributes. If confirmed, the planet will be known as PDS 70D and will remain buried in a thick layer of dust.
“What is interesting is that this separation places it near 1:2:4 mean-motion resonance with planets PDS 70B and PDS 70C. This means its orbit would be almost exactly twice as short as B and four times shorter than planet C, respectively,” said Christiaens.
“This is a situation we know in the solar system with the three innermost Galilean moons of Jupiter: Io, Europa, and Ganymede,” the astronomer said.