New photos sent back by NASA’s New Horizons spacecraft reveal mysterious light patches and dark divots on the strange, frozen space rock known as 2014 MU69. These photos are the clearest ones yet, giving scientists the chance to explore the distant object’s terrain from 4.1 billion miles away.

Located in the Kuiper belt, a stretch of frozen objects at the edge of the Solar System, 2014 MU69 is the most distant object humanity’s gotten a close-up look at, according to a Johns Hopkins University Applied Physics Laboratory news release. It’s roughly 20 miles long, and it’s thought to be basically unchanged since the Solar System’s early days — making it a tiny, enticing, far-away object to study.

Early on New Year’s Day, NASA’s New Horizons spacecraft zoomed as close as 2,200 miles away from 2014 MU69, speeding by at more than 32,000 miles per hour. The spacecraft collected data and snapped photos as it flew by. And each batch of photos that New Horizons sends back from the flyby helps refine our image of 2014 MU69. The first batch revealed a lumpy, misshapen space peanut composed of two touching lobes — called a contact binary. Then earlier in February, New Horizons sent back photos that showed the misshapen space peanut was, in fact, more pancaked than plump.

Now, Johns Hopkins University Applied Physics Laboratory has released the best photos yet. They show off the surface of 2014 MU69 at a resolution of 110 feet per pixel, thanks to the spacecraft’s telephoto Long Range Reconnaissance Imager, or LORRI. The photos were snapped from roughly 4,100-plus miles away with a 0.025-second exposure time, revealing strange light freckles and dark dents that scientists are still trying to figure out. As John Spencer, deputy project scientist from the Southwest Research Institute, says in a statement: “Whether these features are craters produced by impactors, sublimation pits, collapse pits, or something entirely different, is being debated in our science team.”

More images are available on the website for the mission’s Long Range Reconnaissance Imager, where pictures from New Horizons are uploaded every Friday.