Using data from the European Space Agency’s Gaia spacecraft and its predecessor, the long-retired Hipparcos, astronomers have managed to deduce the mass of a young exoplanet for the first time, an achievement made possible by more than a quarter century of observations.
The planet in question, Beta Pictoris b, was discovered in 2008. The new estimate of its mass indicates it is a gas giant nine to 13 times more massive than Jupiter.
The Beta Pictoris system is intriguing because the star is believed to have ignited just 20 million years or so ago, giving astronomers a ringside seat for a solar system in the process of forming. But the system’s youth also makes it difficult to obtain the sort of precise measurement.