ALMA | ESO | NAOJ | NRAO | 2016 June 28
[c][attachment=0]160627image1-eng[1].jpg[/attachment][/c][hr][/hr]Researchers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered a rotating ring containing large organic molecules around a protostar. This observation definitively shows that organic materials formed in interstellar space are brought into the planet-forming region. Researchers also found that the molecular species brought into the planet-forming region vary from one protostar to another. Chemical composition is a new way to answer the long-standing question of whether or not the Solar System is a typical example of a planetary system.
Astronomers have long known that organic molecules form in diffuse gas clouds floating between stars. It is thought that as the Solar System formed 4.6 billion years ago, some of these organic molecules were transported from interstellar space to the planet forming disk. Later, these molecules played important roles in the chemical evolution resulting in the emergence of life on the Earth. However, it is still unknown what kinds and quantities of organic molecules were actually supplied from interstellar space. Although radio astronomy observations during the last decade showed that saturated complex organic molecules, such as methanol (CH3OH) and methyl formate (HCOOCH3), exist around Solar-type protostars, their distributions were too compact to be resolved with the radio telescopes available at the time.
An international team led by Yoko Oya, a graduate student from the Department of Physics at the University of Tokyo, and Nami Sakai, an associate chief scientist of RIKEN, studied with ALMA the distribution of various organic molecules around a Solar-type protostar, IRAS 16293-2422A, at a high spatial resolution. They discovered a ring structure of complex organic molecules around the protostar. The radius of the ring is 50 times wider than the Earth’s orbit. This size is comparable to the size of the Solar System, and the ring structure most likely represents the boundary region between infalling gas and a rotating disk structure around the protostar. ...
Infalling-Rotating Motion and Associated Chemical Change in
the Envelope of IRAS 16293-2422 Source A Studied with ALMA - Yoko Oya et al
- Astrophysical Journal 824(2):88 (20 June 2016) DOI: 10.3847/0004-637X/824/2/88
arXiv.org > astro-ph > arXiv:1605.00340 > 02 May 2016