2M1207

Planetary system

Like classical T Tauri stars, many brown dwarfs are surrounded by disks of gas and dust which accrete onto the brown dwarf. 2M1207 was first suspected to have such a disk because of its broad Hα line. This was later confirmed by ultraviolet spectroscopy. and with ALMA. In general, accretion from disks are known to produce fast-moving jets, perpendicular to the disk, of ejected material. This has also been observed for 2M1207; an April 2007 paper in the Astrophysical Journal reports that this brown dwarf is spouting jets of material from its poles. The jets, which extend around 109 kilometers into space, were discovered using the Very Large Telescope (VLT) at the European Southern Observatory. Material in the jets streams into space at a few kilometers per second. While previous observations with the Spitzer spectrograph already detected acetylene (C2H2) emission in the disk of 2M1207, new observations with MIRI revealed emission of a wide variety of chemicals in the disk, showing a carbon-rich chemistry. In this study 2M1207 and ISO-ChaI 147 showed the largest number of organic molecules, including the only detection of ethylene (C2H4) in this sample. The detected chemicals include 9 hydrocarbons, with diacetylene (C4H2) and benzene (C6H6) being two prominent emission lines in the spectrum of 2M1207. Other emissions by chemicals in the disk are hydrogen gas (H2), hydrogen cyanide (HCN) and carbon dioxide (CO2).

2M1207b shows weak accretion from a disk, inferred from emission lines of hydrogen and helium in medium-resolution NIRSpec data. Surprisingly 2M1207b does not show absorption due to methane, which was predicted to be present for this object. It was suggested that very young objects have a L/T-transition starts at a later spectral type.

Notes

References

References

1. {{cite constellation. 2M1207
2. (2008). "An accurate distance to 2M1207Ab". Astronomy & Astrophysics.
3. {{Cite Gaia DR3. 3459372646830687104
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6. "TWA 27".
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