page_title: Elias 2-27
section_title: Disc
hierarchical_section_title: Elias 2-27 / Disc
caption_attribution_description: English: This beautiful image, captured with the Atacama Large Millimeter/submillimeter Array (ALMA) features a protoplanetary disc surrounding the young stellar object Elias 2-27, some 450 light years away. ALMA has discovered and observed plenty of protoplanetary discs, but this disc is special as it shows two distinct spiral arms, almost like a tiny version of a spiral galaxy. Previously, astronomers noted compelling spiral features on the surfaces of protoplanetary discs, but it was unknown if these same spiral patterns also emerged deep within the disc where planet formation takes place. ALMA, for the first time, was able to peer deep into the mid-plane of a disk and discovered the clear signature of spiral density waves. Nearest to the star, ALMA found a flat disc of dust, which extends to what would approximately be the orbit of Neptune in our own Solar System. Beyond that point, in the region analogous to our Kuiper Belt, ALMA detected a narrow band with significantly less dust, which may be an indication for planet in formation. Springing from the outer edge of this gap are the two sweeping spiral arms that extend more than 10 billion kilometers away from their host star. The discovery of spiral waves at these extreme distances may have implications on the theory of planet formation. Paper detailing Elias 2-27: http://science.sciencemag.org/content/353/6307/1519.full
context_page_description: Elias 2-27 is a YSO star with a protoplanetary disc around it, located in the Ophiuchus Molecular Cloud, a star-forming region in the Ophiuchus constellation, some 450 light-years away. This star system became the first ever observed with density waves in the disc, giving it a spiral structure. Elias 2-27 is located near the double star Rho Ophiuchi.
context_section_description: In 2016, it was discovered that disc perturbations from density waves organized the disc debris into a pinwheel structure, with sweeping spiral arms; using observations from the Atacama Large Millimeter Array (ALMA) radio telescope. This marks the first instance of such an observation in a protoplanetary disc, though they have been previously predicted. The spiral arms start at 100 AU (9.3×10⁹ mi; 1.5×10¹⁰ km) and extend out to 300 AU (2.8×10¹⁰ mi; 4.5×10¹⁰ km).
caption: Protoplanetary disk surrounding the young star Elias 2-27, located some 450 light years away.[4]
exif: {"Image ImageDescription": "This beautiful image, captured with the Atacama Large Millimeter/submillimeter Array (ALMA) features a protoplanetary disc surrounding the young star Elias 2-27, some 450 light years away. ALMA has discovered and observed plenty of protoplanetary discs, but this disc is special as it shows two distinct spiral arms, almost like a tiny version of a spiral galaxy. Previously, astronomers noted compelling spiral features on the surfaces of protoplanetary discs, but it was unknown if these same spiral patterns also emerged deep within the disc where planet formation takes place. ALMA, for the first time, was able to peer deep into the mid-plane of a disk and discovered the clear signature of spiral density waves. Nearest to the star, ALMA found a flat disc of dust, which extends to what would approximately be the orbit of Neptune in our own Solar System. Beyond that point, in the region analogous to our Kuiper Belt, ALMA detected a narrow band with significantly less dust, which may be an indication for planet in formation. Springing from the outer edge of this gap are the two sweeping spiral arms that extend more than 10 billion kilometers away from their host star. The discovery of spiral waves at these extreme distances may have implications on the theory of planet formation.", "Image Software": "Adobe Photoshop CC 2015 (Macintosh)", "Image DateTime": "2016:09:30 10:32:23"}