Star caught devouring Pluto-like object, hinting at fate of Solar System

09/21/2025 Astronomy

Space is a pretty wild place, and sometimes, things get downright brutal. Recently, astronomers using the Hubble Space Telescope witnessed a white dwarf—basically, the leftover core of a dead star—chowing down on something that used to be a Pluto-like object. I mean, can you imagine being a tiny, icy world getting devoured by a stellar remnant?

According to research published in the Monthly Notices of the Royal Astronomical Society, it seems this white dwarf had already been at its "meal" for a while. The star’s intense gravity probably yanked the icy planet from its usual orbit, setting it on a collision course with doom. It's like a cosmic game of cat and mouse, except the mouse is an entire planet, and the cat is a stellar corpse.

What makes this discovery even cooler is what they found out about the doomed object. Its composition included stuff like carbon, sulfur, nitrogen, and oxygen, which suggests it might have even had water on its surface at some point. It's mind-blowing to think that a world meeting such a violent end could once have potentially harbored the building blocks of life.

Typically, a white dwarf's atmosphere is made of hydrogen and helium. But this particular one, named WD 1647+375, had a strange amount of volatiles – chemical substances that melt easily. This tipped off the researchers that something wasn't quite right.

Cosmic Forensics

As the lead author of the study, Snehalata Sahu, pointed out, "White dwarfs act like cosmic crime scenes." When these small, solid objects thought to form planets fall in, their elements leave chemical fingerprints in the star’s atmosphere, letting astronomers figure out the identity of the victim. The team noticed a lot of nitrogen, which is a key sign of icy worlds. The star also had more oxygen than if it had eaten a rocky object. Sahu mentioned that Pluto's surface is covered in nitrogen ices, so they believe the white dwarf consumed parts of a dwarf planet's crust and mantle.

Hubble's ultraviolet signals showed that the star had been feasting for at least 13 years, gobbling up the object at about 440,925 pounds per second! That means the victim, when it was whole, would have been at least 3 miles in diameter. All the evidence suggests WD 1647+375 was snacking on an icy planetesimal from its local version of the Kuiper Belt.

This discovery isn't just a weird cosmic event; it gives us a glimpse into the past and future of solar systems. These icy planetesimals might be crucial for delivering water and other volatile substances to planets, which, as we know, is essential for life.

But perhaps the most fascinating aspect is what this tells us about our own future. Our Sun will eventually become a white dwarf, just like WD 1647+375. When that happens, the planets in our solar system could face a similar fate. According to Sahu, an alien observer in the distant future might see the same kind of stellar carnage around our dead Sun.