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JuMBOs: Newly-discovered, free-floating worlds that can't be explained

NASA’s James Webb Space Telescope (JWST) has made a groundbreaking discovery of Jupiter-sized “planets” freely floating in space, unattached to any stars. These intriguing objects, observed within the Orion Nebula, are referred to as Jupiter Mass Binary Objects, or “JuMBOs” for short.

Orion Nebula 

In a recent detailed survey of the Orion Nebula, the JWST identified approximately 40 pairs of JuMBOs. These mysterious objects are remarkable for their autonomous movement in pairs, a phenomenon that currently puzzles astronomers. 

The Orion Nebula (M42) is an expansive star-forming region located about 1,400 light-years from Earth. This star-forming region has long fascinated researchers and has been significantly illuminated by the high-resolution and infrared sensitivity capacities of the JWST.

Mysterious origins

The origin and nature of JuMBOs are shrouded in mystery. According to Professor Mark McCaughrean, the European Space Agency‘s (ESA) senior science advisor, there are a couple of prevailing theories. 

The first speculates that JuMBOs emerged from nebula regions with insufficient material density to form full-fledged stars. The second hypothesis suggests these objects originally formed around stars before being ejected into interstellar space through various interactions.

Unexplained questions 

“Gas physics suggests you shouldn’t be able to make objects with the mass of Jupiter on their own, and we know single planets can get kicked out from star systems. But how do you kick out pairs of these things together? Right now, we don’t have an answer. It’s one for the theoreticians,” Professor McCaughrean told BBC News.

The discovery challenges existing astrophysical knowledge. These free-floating objects, despite their size, aren’t considered planets in the traditional sense. 

Distinct characteristics

With an age of approximately one million years, these “babies” in astronomical terms are hot, gaseous bodies enveloped in steam and methane atmospheres. 

Their distinct characteristics, including their gas giant composition similar to Jupiter, negate the possibility of hosting liquid water reservoirs or alien life.

Breaking physics 

Data from ground-based telescopes had previously hinted at the existence of JuMBOs before the JWST formally identified them. 

“We were looking for these very small objects and we find them,” Professor McCaughrean told The Guardian. “We find them down as small as one Jupiter mass, even half a Jupiter mass, floating freely, not attached to a star. Physics says you can’t even make objects that small. We wanted to see, can we break physics? And I think we have, which is good.”

New category of worlds

The term “binary,” incorporated into the name of JuMBOs, reflects the observation that some of these objects move in pairs, comparable to binary solar systems with two stars. 

Overall, the discovery of JuMBOs presents an exciting mystery for astronomers and theoreticians alike. 

As these objects cannot be easily classified as either stars or planets, they represent an entirely new category of celestial bodies, challenging and expanding the existing boundaries of astronomical knowledge and understanding. 


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