A curious mix of dust and gas surrounding a distant star presents a unique mystery – and possibly a front-row seat to planet formation, according to Assistant Professor of Astronomy Meredith Hughes and colleagues, whose paper on the star appears in the March 6 edition of the journal Science.
The group of astronomers, including Hughes and 13 others, were the first to identify the asymmetry and “lumpy” quality of the gas surrounding beta Pictoris, using data from the Atacama Large Millimeter/Submillimeter Array (ALMA) in Chile. The discovery leads to two possible explanations: There may be a giant “exoplanet” lurking nearby (forcing clumps of carbon dioxide to orbit the star on opposite sides) or there has recently been a collision between two Mars-sized bodies. More data must be analyzed to figure out which event happened.
“We actually already knew that there was gas around this star, but we didn’t know how much, or that the gas would be lumpy and asymmetric – the asymmetry is another indication that the gas was probably generated by a recent collision,” explained Hughes.
Beta Pictoris, which is actually a stellar neighbor of Earth, about 60 light years away, is in an active place for planet formation, Hughes said. And the evidence discussed in the Science paper points toward very recent (on astronomical timescales – in this case probably thousands of years) events. (more…)