Free Astronomy Magazine May-June 2025

40 MAY-JUNE 2025 ASTRO PUBLISHING direct imaging of exoplanets, plan- ets outside our solar system, with NASA’s Nancy Grace Roman Space Telescope, which is scheduled to begin operations in 2027. SIMP 0136 is a rapidly rotating, free- floating object roughly 13 times the mass of Jupiter, located in the Milky Way just 20 light-years from Earth. Although it is not classi- fied as a gas giant exo- planet — it doesn’t orbit a star and may instead be a brown dwarf — SIMP 0136 is an ideal target for exo-mete- orology: It is the brightest ob- ject of its kind in the northern sky. Because it is isolated, it can be A n international team of re- searchers has discovered that previously observed varia- tions in brightness of a free-floating planetary-mass object known as SIMP 0136 must be the result of a complex combination of atmos- pheric factors, and cannot be ex- plained by clouds alone. Using NASA’s James Webb Space Tel- escope to monitor a broad spectrum of infrared light emitted over two full rotation periods by SIMP 0136, the team was able to detect varia- tions in cloud layers, temperature, and carbon chemistry that were pre- viously hidden from view. The results provide crucial insight into the three-dimensional complex- ity of gas giant atmospheres within and beyond our solar system. De- tailed characterization of objects like these is essential preparation for Webb exposes complex atmosphere of starless super-Jupiter by NASA/ESA/CSA Margaret W. Carruthers Hannah Braun T his artist’s concept shows what the isolated planetary-mass object SIMP 0136 could look like based on recent observations from NASA’s James Webb Space Telescope and previous observations from Hubble, Spitzer, and numerous ground-based telescopes. SIMP 0136 is about 13 times the mass of Jupiter. Al- though it is thought to have the structure and composition of a gas giant, it is not technically classified as an exoplanet because it doesn’t orbit its own star. The colors shown in the illustration represent near-infrared light, which is in- visible to human eyes. SIMP 0136 is relatively warm — about 1,500 degrees Fahrenheit (825 degrees Celsius or 1,100 kelvins) — but is not hot enough to give off enough visible light to see from Earth, and is not illuminated by a host star. The bluish glow near the poles represents auroral energy (light given off by electrons spiraling in a magnetic field) which has been detected at radio wavelengths. [NASA, ESA, CSA, Joseph Olmsted (STScI)]