![\"A](\"https:\/\/aasnova.org\/wp-content\/uploads\/2026\/06\/tmp.jpg\")
<\/a><\/p>\nAn illustration of how exoplanets are found via microlensing. The broad first bump is caused by the host star magnifying the light from a background star; the narrow second bump is caused by the planet acting as a lens as well. \u201cFree-floating\u201d planets create only one bump. [Adapted from NASA, ESA, and A. Feild (STScI)<\/a>]<\/p>\n The idea that there are more free-ranging Neptunes than stars is unsettling, and astronomers aren\u2019t yet sure how this many planets ended up so isolated. It\u2019s possible that these objects simply formed disconnected from any planetary system, but it\u2019s unclear how something so small could collapse from the interstellar clouds that usually produce stellar-mass objects. It\u2019s also possible that the planets formed around stars in the usual way, only to be later kicked out by some violent dynamical process \u2014 but this would either require too much time or too many giant planets capable of ejecting the lower-mass ones.<\/p>\n However, new research by Sam Hadden (Canadian Institute for Theoretical Astrophysics) and Yanqin Wu (University of Toronto) presents an alternative idea: what if at least some of these free-floating planets aren\u2019t fully on their own, but instead remain estranged but weakly bound to their parent stars?<\/p>\n Simulated Scattering<\/p>\n Two celestial objects need to align nearly perfectly in order to create a microlensing pulse that we can detect. For an exoplanet orbiting a star, we should observe two of these pulses: one when the host star drifts in and out of alignment with a background star, and one when the nearby bound planet does the same. In the case of a free-floating planet, there\u2019s only one pulse, and we therefore assume that there is no host star. Hadden and Wu noticed that since the alignment has to be so precise for microlensing to occur, it\u2019s possible that a seemingly free-floating planet is simply widely separated from its host star, and the star managed to dodge the magnification effect. In other words, these planets might not be free floating at all, just on wide and eccentric orbits.<\/p>\n