Over 100 New Minor Planets Found at the Edge of the Solar System: Study

Astronomers have discovered more than 100 new trans-Neptunian objects (TNOs), minor planets located in the far reaches of the solar system. For the study, published in The Astrophysical Journal Supplement Series, the researchers used data from Dark Energy Survey (DES), an international collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our universe.

The study also describes a new approach for finding similar types of objects and could aid future searches for the hypothetical Planet Nine and other undiscovered planets.

"The number of TNOs you can find depends on how much of the sky you look at and what's the faintest thing you can find," said Gary Bernstein, Professor at the University of Pennsylvania in the US.

Using the first four years of DES data, Pedro Bernardinelli from the University of Pennsylvania started with a dataset of seven billion "dots," all of the possible objects detected by the software that were above the image's background levels.

He then removed any objects that were present on multiple nights - things like stars, galaxies, and supernova - to build a "transient" list of 22 million objects before commencing a massive game of "connect the dots," looking for nearby pairs or triplets of detected objects to help determine where the object would appear on subsequent nights.

With the seven billion dots whittled down to a list of around 400 candidates that were seen over at least six nights of observation, the researchers then had to verify their results.

"We have this list of candidates, and then we have to make sure that our candidates are actually real things," Bernardinelli said.

To filter their list of candidates down to actual TNOs, the researchers went back to the original dataset to see if they could find more images of the object in question.

Bernardinelli developed a way to stack multiple images to create a sharper view, which helped confirm whether a detected object was a real trans-Neptunian object.

They also verified that their method was able to spot known trans-Neptunian objects in the areas of the sky being studied and that they were able to spot fake objects that were injected into the analysis.

After many months of method-development and analysis, the researchers found 316 TNOs, including 245 discoveries made by DES and 139 new objects that were not previously published.