The deepest and most comprehensive photo of the Orion Nebula — located roughly 1,350 light-years away from Earth — has revealed a preponderance of faint brown dwarfs and planetary-mass objects. The photograph, captured using the European Southern Observatory’s (ESO) infrared instrument on the Very Large Telescope in Chile, is not only providing invaluable insights into the history of star formation in the nebula, it is also challenging assumptions about how stars and planets form.
The image reveals 10 times as many planet-mass objects and failed stars called brown dwarfs than previously known. This means that the Orion Nebula, which can be seen as a fuzzy “star” in the middle of Orion’s sword in the constellation, is forming way more planets and far fewer stars than scientists had estimated.
“Understanding how many low-mass objects are found in the Orion Nebula is very important to constrain current theories of star formation. We now realise that the way these very low-mass objects form depends on their environment,” team member Amelia Bayo from University of Valparaíso in Chile, said in a statement.
The image also suggests that low mass brown dwarfs — objects that have the awkward distinction of being too large to be called planets and too small to be categorized as stars — may be more common than observations so far suggest. These so-called failed stars are extremely dim as compared to their hotter counterparts, but their heat signatures light up when viewed in infrared images.
Although the technology to observe these objects does not exist yet, scientists hope that the ESO’s future European Extremely Large Telescope (E-ELT), which is scheduled to begin operations in 2024, would provide further clues to what exactly is going on inside the nebula.
“Our result feels to me like a glimpse into a new era of planet and star formation science. The huge number of free-floating planets at our current observational limit is giving me hope that we will discover a wealth of smaller Earth-sized planets with the E-ELT,” lead scientist Holger Drass from Germany’s Astronomisches Institut said in the statement.