Detailed new images of the starbirth nursery in the Omega Nebula (M17) have
revealed a multi component structure in the envelope of dust and gas surrounding a very young star. The stellar newborn, called M17-SO1, has a flaring torus of gas and dust, and thin conical shells of material above and below the torus. Shigeyuki Sako from
University of Tokyo and a team of astronomers from the
National Astronomical Observatory of Japan,
Japan Aeorospace Exploration Agency,
Ibaraki University,
Purple Mountain Observatory of the
Chinese Academy of Sciences, and
Chiba University obtained these images and analyzed them in infrared wavelengths in order to understand the mechanics of protoplanetary disk formation around young stars.
Stellar Envelope (Courtesy: NAOJ)Their work is described in a detailed article in the April 21, 2005 edition of
Nature. The near-infrared observations reveal the structure of the surrounding envelope with unprecedented levels of detail. The observations show that the envelope has multiple components instead of one simple structure. The discovery of the multi-component structure puts new constraints on how an envelope feeds material to a protostellar disk forming within its boundaries.
The Sun and the solar system formed from a dense cloud of gas and dust similar to M17-SO1 some 4.6 billion years ago. All the material that makes up the Earth and the creatures that live upon it originated in that primordial cloud. Once the Sun formed, its gravity pulled gas and dust inward. When the Sun's gravitational pull and the centrifugal force of the infalling material balanced, the remaining material settled into orbit around the Sun. The resulting disk of gas and dust was a protoplanetary disk. Repeated collisions of gas and dust within this disk led to the formation of the planets. To understand what the early solar system was like, and to understand how planetary systems form in general, astronomers are actively studying stars that could be similar to the Sun as it was 4.6 billion years ago.
The observations regarding this planetary envelope can be substantial in extending our understanding of the proto-disk that once surrounded our Sun.
