#Hubble Watches How a Giant #Planet Grows
Exoplanet PDS 70b is gobbling up gas and dust as it continues to build mass.
Ever made a complete mess in your kitchen while baking? At moments it may look like flour is floating in the air, but once you’ve added plenty of water and formed your dough, the bread becomes more like a ball. A similar process is at work in a far-flung solar system known as PDS 70, except the flour and water are swapped for gas and dust. In the case of planet PDS 70b, gas and dust are slowly being drawn in as this distant world builds mass over millions of years.
Researchers using Hubble directly measured the mass growth rate of PDS 70b for the first time by using the observatory’s unique ultraviolet sensitivities to capture radiation from extremely hot gas falling onto the planet. The massive, Jupiter-sized world orbits at approximately the same distance as Uranus does from the Sun – though it slogs through a mess of gas and dust as it moves through the solar system. The planet, which began forming approximately 5 million years ago, may be in the tail end of its formation process. The researchers’ findings break open a new way to study forming planets that could aid other astronomers seeking to learn more about how giant planets grow in remote solar systems.