Researchers have found more than 300 trans-Neptunian objects in the solar system, of which more than 100 are new discoveries. Trans-Neptunian objects are minor planets orbiting the Sun, yet further away than Neptune. A widely known example is Pluto, a former planet that lost its status in 2006 and is now a dwarf planet. These minor planets were recorded in a study led by Pedro Bernardinelli, Gary Bernstein and Masao Sako, who used data from the Dark Energy Survey.
The Dark Energy Survey, a now-completed six-year data survey, is a collection of high-precision images of the southern sky taken to understand the nature of dark energy. This survey was designed to record supernovas and galaxies, yet researchers needed to be able to track movement differently to study trans-Neptunian objects. Their solution: surveys that sometimes took measurements only one or two hours apart.
The study, published in The Astrophysical Journal Supplement Series, also required Bernardinelli to remove objects that appeared on multiple nights from the dataset of seven billion ‘dots’, all of which were possible objects identified by software. Researchers then verified the 400 remaining candidates, those that had been observed over a minimum of six nights – possible minor planets. By returning to the original data set to look for more images of these objects, ones which may not have been registered as ‘dots’, and by stacking the images, the team was then able to identify minor planets.
The researchers are now repeating their analyses using a lower threshold with the hopes of finding new Trans-Neptunian Objects – they estimate possibly as many as 500 could be found. Bernardinelli’s method is also to be used in future astronomical surveys.