A blue ring nebula from a stellar merger several thousand years ago
نویسندگان
چکیده
منابع مشابه
Islamic medical ethics a thousand years ago.
F several centuries, the world, and particularly Europe has benefited from the great contributions brought about by Muslim physicians in the field of medicine. These contributions were not only based on technical skills but also on the role of eminent Muslim physicians in establishing medical ethics. Many prominent physicians of the Islamic civilization involved themselves with professional eth...
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Collisions in the asteroid belt frequently lead to catastrophic breakups, where more than half of the target's mass is ejected into space. Several dozen large asteroids have been disrupted by impacts over the past several billion years. These impact events have produced groups of fragments with similar orbits called asteroid families. Here we report the discovery of a very young asteroid family...
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To the Editor: The identification of highly polymorphic markers, which are widely distributed throughout the human genome, has allowed the mapping of several disease genes. These markers have been used to analyze the origin, in time and place, of the most prevalent mutations for different diseases, such as cystic fibrosis (Morral et al. 1994), idio-pathic torsion dystonia (Risch et al. 1995), h...
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We present new, NTT longslit spectroscopy of the B[e] supergiant in the binary system R4 in the Small Magellanic Cloud. The data show extended, forbidden N and S emissions which are typical signatures of circumstellar matter. Their extension along the space axis of the slit defines an angular size of 8.6 ′′ which translates into a linear size of 2.4 pc. The N emission lines also show the veloci...
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Here, we present direct measurements of atmospheric composition and Antarctic climate from the mid-Pleistocene (∼1 Ma) from ice cores drilled in the Allan Hills blue ice area, Antarctica. The 1-Ma ice is dated from the deficit in (40)Ar relative to the modern atmosphere and is present as a stratigraphically disturbed 12-m section at the base of a 126-m ice core. The 1-Ma ice appears to represen...
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ژورنال
عنوان ژورنال: Nature
سال: 2020
ISSN: 0028-0836,1476-4687
DOI: 10.1038/s41586-020-2893-5