This mosaic shows 30 of 74 recently discovered exocometary belts — swaths of rocky, icy material left over after planet formation — around nearby stars. They were discovered by the REsolved ALMA and SMA Observations of Nearby Stars (REASONS) survey, which uses the Atacama Large Millimeter/submillimeter Array and the Submillimeter Array radio observatories. These observatories pick up light from roughly millimeter-sized “pebbles” in the belts, which lie at distances from their stars that are some tens to hundreds of times the distance of Earth from the Sun. At those locations, temperatures range from –240 to –420 degrees Fahrenheit (–150 to –250 degrees Celsius) and volatile compounds like water and carbon dioxide are present only as ices. These are the reservoirs from which most comets originate.
According to the researchers conducting…
You're reading a preview of
Astronomy (Digital) - 1 Issue, May 2025