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Scientists have been closely studying SIMP 0136, a free-floating planetary-mass object located 20 light-years from Earth, using the James Webb Space Telescope. Unlike planets that orbit stars, SIMP 0136 drifts alone through space, making it an ideal subject for study without interference from a nearby star. With a mass about 13 times greater than Jupiter and a fast rotation period of just 2.4 hours, it exhibits fluctuating brightness due to varying levels of infrared radiation, which researchers believe stems from complex atmospheric processes like patchy clouds, temperature shifts, and possibly auroral activity.

Using Webb’s Near-Infrared Spectrograph (NIRSpec) and Mid-Infrared Instrument (MIRI), scientists observed how different wavelengths revealed varying atmospheric depths and compositions. Some infrared light came from iron and silicate clouds, while other wavelengths revealed bright hotspots above the cloud layers. The variations in brightness suggest chemical changes over time, with methane and carbon dioxide levels differing across the planet. Researchers caution that single observations may not represent the full nature of such planets, highlighting the importance of capturing broad data to better understand atmospheric and chemical dynamics on untethered worlds like SIMP 0136.