ALMA tagged posts

Another Close-by Planetary System?

This artist's impression shows how the newly discovered belts of dust around the closest star to the Solar System, Proxima Centauri, may look. ALMA observations revealed the glow coming from cold dust in a region between one to four times as far from Proxima Centauri as the Earth is from the Sun. The data also hint at the presence of an even cooler outer dust belt and indicate the presence of an elaborate planetary system. These structures are similar to the much larger belts in the Solar System and are also expected to be made from particles of rock and ice that failed to form planets. Note that this sketch is not to scale -- to make Proxima b clearly visible it has been shown further from the star and larger than it is in reality. Credit: ESO/M. Kornmesser

This artist’s impression shows how the newly discovered belts of dust around the closest star to the Solar System, Proxima Centauri, may look. ALMA observations revealed the glow coming from cold dust in a region between one to four times as far from Proxima Centauri as the Earth is from the Sun. The data also hint at the presence of an even cooler outer dust belt and indicate the presence of an elaborate planetary system. These structures are similar to the much larger belts in the Solar System and are also expected to be made from particles of rock and ice that failed to form planets. Note that this sketch is not to scale — to make Proxima b clearly visible it has been shown further from the star and larger than it is in reality. Credit: ESO/M. Kornmesser

ALMA discovers cold dust around ...

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Shedding Light on Galaxies’ Rotation Secrets

Image: . Angular Momentum of Early- and Late-type Galaxies: Nature or Nurture? The Astrophysical Journal, 2017; 843 (2): 105 DOI: 10.3847/1538-4357/aa7893

Image: . Angular Momentum of Early- and Late-type Galaxies: Nature or Nurture? The Astrophysical Journal, 2017; 843 (2): 105 DOI: 10.3847/1538-4357/aa7893

The dichotomy concerns the so-called angular momentum (per unit mass), that in physics is a measure of size and rotation velocity. Spiral galaxies are found to be strongly rotating, with an angular momentum higher by a factor of about 5 than ellipticals. What is the origin of such a difference? An international research team investigated the issue in a study just published in the Astrophysical Journal. The team was led by SISSA Ph.D. student JingJing Shi under the supervision of Prof. Andrea Lapi and Luigi Danese, and in collaboration with Prof. Huiyuan Wang from USTC (Hefei) and Dr. Claudia Mancuso from IRA-INAF (Bologna). The res...
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Cosmic ‘Dust factory’ reveals clues to how Stars are Born

This artist's illustration of Supernova 1987A reveals the cold, inner regions of the exploded star's remnants (red) where tremendous amounts of dust were detected and imaged by ALMA. This inner region is contrasted with the outer shell (blue), where the energy from the supernova is colliding (green) with the envelope of gas ejected from the star prior to its powerful detonation. Credit: A. Angelich; NRAO/AUI/NSF

This artist’s illustration of Supernova 1987A reveals the cold, inner regions of the exploded star’s remnants (red) where tremendous amounts of dust were detected and imaged by ALMA. This inner region is contrasted with the outer shell (blue), where the energy from the supernova is colliding (green) with the envelope of gas ejected from the star prior to its powerful detonation. Credit: A. Angelich; NRAO/AUI/NSF

A group of scientists led by researchers at Cardiff University have discovered a rich inventory of molecules at the centre of an exploded star for the very first time. 2 previously undetected molecules, formylium (HCO+) and sulphur monoxide (SO), were found in the cooling aftermath of Supernova 1987A, 163,000 light years away in a nearby neighbour of our own Milky Way galaxy...

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Re-Making Planets after Star-Death

1. Data at wavelength of 0.45 mm, combined from SCUBA and SCUBA-2, in a false-colour image. The Geminga pulsar (inside the black circle) is moving towards the upper left, and the orange dashed arc and cylinder show the ‘bow-wave’ and a ‘wake’. The region shown is 1.3 light-years across; the bow-wave probably stretches further behind Geminga, but SCUBA imaged only the 0.4 light-years in the centre. Credit: Jane Greaves / JCMT / EAO. 2. Sketch of the nebula formed by a wind of electrons and positrons coming from the pulsar, and the interaction with interstellar gas. Geminga crossed the plane of the Galaxy (off to the bottom right) around 100,000 years ago. It is thought that the supernova explosion was not symmetric, causing the remnant to recoil at around 200 km per second from its birth location. Credit: Jane Greaves / University of Cardiff.

1. Data at wavelength of 0.45 mm, combined from SCUBA and SCUBA-2, in a false-colour image. The Geminga pulsar (inside the black circle) is moving towards the upper left, and the orange dashed arc and cylinder show the ‘bow-wave’ and a ‘wake’. The region shown is 1.3 light-years across; the bow-wave probably stretches further behind Geminga, but SCUBA imaged only the 0.4 light-years in the centre. Credit: Jane Greaves / JCMT / EAO. 2. Sketch of the nebula formed by a wind of electrons and positrons coming from the pulsar, and the interaction with interstellar gas. Geminga crossed the plane of the Galaxy (off to the bottom right) around 100,000 years ago...

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