Astronomers have identified a young star with four alien planets orbiting around it. This system lies 500 light-years from Earth.
The newfound star is CI Tau which is just 2 million years old. In comparison, our own star is nearly 5 billion years old. A swirling clump of dust and gas, a protoplanetary disk, surrounds the star. So, CI Tau is so young that the material around it hasn’t finished forming planets.
But there are four gas giants in orbit around it. This is the first time so many massive planets have been detected in such a young system.
Two of them are bigger than Jupiter, and the other two are Saturn-sized. The innermost planet is one of the biggest planets ever discovered, about ten times the size of Jupiter. That’s huge.
The newfound planets have really different orbits. The hot Jupiter, the closest to its star, is within the equivalent of the orbit of Mercury. But the farthest planet orbits at a distance more than three times greater than that of Neptune.
However, the shape of the outermost planets is pretty unclear.
“Saturn-mass planets are supposed to form by first accumulating a solid core and then pulling in a layer of gas on top, but these processes are supposed to be very slow at large distances from the star,” study lead author Cathie Clarke, of the Institute of Astronomy at the University of Cambridge in England, said in a statement. “Most models will struggle to make planets of this mass at this distance.”
Scientists already knew that CI Tau was home to one planet. A team of researchers led by the University of Cambridge have used the Atacama Large Millimeter/submillimeter Array (ALMA) to search for planetary ‘siblings’ to this infant hot Jupiter. Their image revealed three gaps in the star’s protoplanetary disk, at distances of 13, 39 and 100 astronomical units (AU) from the star. So, their theoretical modeling suggests that three additional gas giant planets have carved these gaps. Researchers have reported their results in the Astrophysical Journal Letters.
Furthermore, scientists will study this puzzling system at multiple wavelengths. Thus, acquiring more knowledge about the properties of the disc and its planets.
Thumbnail image credit: University of Cambridge