Free Astronomy Magazine January-February 2025

47 JANUARY-FEBRUARY 2025 ASTRO PUBLISHING fully analyzing the various spectral emission lines from multiple ele- ments present in the COS spectrum. This should provide further clues on FU Ori’s environment, such as the kinematics of inflowing and out- flowing gas within the inner region. “A lot of these young stars are spec- troscopically very rich at far ultravio- let wavelengths,” reflected Hillen- brand. “A combination of Hubble, its size and wavelength coverage, as well as FU Ori’s fortunate circum- stances, let us see further down into the engine of this fascinating star- type than ever before.” emits a lot of ultraviolet light. Un- derstanding the mechanisms of FU Ori’s rapid accretion process relates more broadly to ideas of planet for- mation and survival. “Our revised model based on the Hubble data is not strictly bad news for planet evolution, it’s sort of a mixed bag,” explained Carvalho. “If the planet is far out in the disk as it’s forming, out- bursts from an FU Ori object should influence what kind of chemicals the planet will ultimately inherit. But if a forming planet is very close to the star, then it’s a slightly different story. Within a cou- ple outbursts, any planets that are form- ing very close to the star can rapidly move inward and eventually merge with it. You could lose, or at least completely fry, rocky planets forming close to such a star.” Additional work with the Hubble UV observations is in progress. The team is care- O ptical RGB composite image of LBN 878 (the red and brown nebula dominating the field) obtained by astrophotographer Jim Thommes. FU Ori (with its reflection nebula) is the bright object located at the center of the image. The inset shows the integrated intensity 12 CO(2–1) maps as traced by the ALMA observations. Red- shifted and blueshifted 12 CO integrated intensity maps of FU Ori are plotted over the optical emis- sion (color scale). The blueshifted moment 0 map (blue contours) was constructed including emission from 8.0 to 11.5 km s −1 , while the redshifted integrated emission (red contours) includes the emission between 12.7 and 17.5 km s −1 . [The Astrophysical Journal (2024)] I mages of four young stellar disks, taken with the Sub- aru telescope (H or K band). Clearly visible are various structures in the disk, such as arms, arcs, streams, or spikes. [NAOJ] !