National Astronomical Observatory of Japan

ALMA Discovers Large “Hot” Cocoon around a Small Baby Star

| Science

International research team, led by researcher at the University of Electro-Communication observed an infrared dark cloud G34.43+00.24 MM3 with ALMA and discovered a baby star surrounded by a large hot cloud. This hot cloud is about ten times larger than those found around typical solar-mass baby stars.

Hot molecular clouds around new-born stars are called “Hot Cores” and have temperature of – 160 degrees Celsius, 100 degrees hotter than normal molecular clouds. The large size of the hot core discovered by ALMA shows that much more energy is emitted from the central baby star than typical solar-mass young stars. This may be due to the higher mass infall rate, or multiplicity of the central baby star. This result indicates a large diversity in the star formation process.

Figure 1
Artist impression of a protostar in the Infrared Dark Cloud MM3. The protostar is surrounded by the large hot gas cloud and emanates bipolar gas outflow.

The research findings are presented in the article “ALMA Observations of the IRDC Clump G34.43+00.24 MM3: Hot Core and Molecular Outflows”, published in the Astrophysical Journal Letters, Vol. 775, of September 20, 2013.