It was previously reported that two planets – PDS 70b and PDS 70c – were orbiting a young star in the constellation Centaurus which is located approximately 370 light-years away from us. And according to new research that is focused on PDS 70b, the planet is huge and is still growing.
PDS 70b, which is about the size of Jupiter, orbits its host star at about the same distance as Uranus orbits our sun (Uranus orbits the sun at a distance of about 1.8 billion miles). The exoplanet is only believed to be about 5 million years ago, meaning that it is young compared to other worlds. It could be in its final stages of growth, so it’s very important that experts study it in order to find out how giant planets grow.
“We just don’t know very much about how giant planets grow,” stated Brendan Bowler from the University of Texas at Austin, adding, “This planetary system gives us the first opportunity to witness material falling onto a planet. Our results open up a new area for this research.”
Thanks to the Hubble Space Telescope, researchers have been able to observe PDS 70b gathering up gas and dust from a circumstellar disk as it continues to grow. They were able to see it gobbling up radiation and hot gas surrounding the orange dwarf star PDS 70 by using the observatory’s ultraviolet equipment.
It is believed that the magnetic field lines go from the circumplanetary disk onto the PDS 70b’s atmosphere and ultimately throwing the space material onto the surface of the planet. Yifan Zhou from the University of Texas at Austin explained this further, “If this material follows columns from the disk onto the planet, it would cause local hot spots,” adding, “These hot patches were found to glow fiercely in UV light.”
Based on their observations so far, they determined that the planet has grown up to five times the mass of Jupiter in 5 million years and if it keeps bulking up at the rate it is going, it could gain another 1/100th of Jupiter’s mass over the next million years. Jupiter is the largest planet in our solar system with a diameter measuring in at about 11 times the size of Earth and 317 times our mass. Despite being the largest planet in the solar system, it has the shortest day as it completes a full rotation in just 10 hours.
Zhou weighed in on the research by saying, “This system is so exciting because we can witness the formation of a planet.” “This is the youngest bona fide planet Hubble has ever directly imaged.” Their research was published in The Astronomical Journal where it can be read in full.
Pictures of PDS 70b can be seen here.