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The Atacama Large Millimeter/submillimeter Array (ALMA) is an international radio telescope under construction in the Atacama Desert of northern Chile. ALMA is situated on a dry site at 5000 m elevation, allowing excellent atmospheric…
The tumuli of Newgrange and Knowth in Ireland are among the most monumental heritages of the Neolithic era. The megalithic constructions date back to around 3'200 BC, centuries before the completion of Stonehenge and the Egyptian pyramids.…
A substantial share of the Earth's land surface is managed by humans, with cities representing the most extreme form of anthropogenic land use. There are zillion ways in which settlements can be arranged across a given area, and their…
The Circle of Apollonius is named after the ancient geometrician Apollonius of Perga. This beautiful geometric construct can be helpful when solving some general problems of mathematical physics, optics and electricity. Here we discuss its…
Finding Hemisystems is a challenging problem and just few examples arising from the Hermitian surface are known. A recent method to obtain Hemisystems is based on using maximal curves. Along this side of research, we provide new examples of…
The Milky Way is a barred spiral galaxy, with physical properties inferred from various tracers informed by the extrapolation of structures seen in other galaxies. However, the distances of these tracers are measured indirectly and are…
We give examples of surfaces which are Ulrich-wild, i.e. that support families of dimension $p$ of pairwise non-isomorphic, indecomposable, Ulrich bundles for arbitrary large $p$.
A complex web of roads, walkways and public transport systems can hide areas of geographical isolation very difficult to analyze. Random walks are used to spot the structural details of urban fabric.
P. Di Francesco first introduced the "Aztec triangle" in his study of the relationship between the twenty-vertex model and domino tilings. He conjectured an exact formula for the number of tilings of the Aztec triangle, and it has since…
The Dwingeloo Obscured Galaxies Survey (DOGS) is a 21-cm blind survey for galaxies hidden in the northern "Zone of Avoidance" (ZOA): the portion of the optical extragalactic sky which is obscured by dust in the Milky Way. Like the Parkes…
According to popular tradition, the Canarian city of San Cristobal de La Laguna, a World Heritage Site by UNESCO since 1999, emerged in the early sixteenth century with a novel organization, in line with a new peaceful social order inspired…
The deepest and clearest maps yet of the Universe's skeleton of dark matter structure present a picture broadly in concord with favoured models - although puzzling discrepancies remain.
The volume contains selected contributions from the Machine Learning Challenge "Discover the Mysteries of the Maya", presented at the Discovery Challenge Track of The European Conference on Machine Learning and Principles and Practice of…
In our systematic optical galaxy search behind the southern Milky Way, 3760 (mostly unknown) galaxies with diameters D > 0.2 arcminutes were identified in the Crux region (287 < l < 318 degrees, |b| < 10 degrees, Woudt & Kraan-Korteweg…
Following previous works on ancient myths in Greek and Latin literature regarding Ursa Major, and the possible relation with the ancient shape of the constellation, we discuss further this case in the light of the evolution of Homo sapiens…
What is the shape of the Universe? Is it finite or infinite ? Is space multi-connected to create ghost images of faraway cosmic sources? After a "dark age" period, the field of cosmic topology has now become one of the major concerns in…
From fairy circles to patterned ground and columnar joints, natural patterns spontaneously appear in many complex geophysical settings. Here, we investigate the origins of polygonally patterned crusts of salt playa and salt pans. These…
We have searched for nearby dwarf galaxies in 27 northern groups with characteristic distances 8-15 Mpc based on the Second Palomar Sky Survey prints. In a total area of about 2000 square degrees, we have found 90 low-surface-brightness…
We derive, in order of magnitude, the observed astrophysical and cosmological scales in the Universe, from neutron stars to superclusters of galaxies, up to, asymptotically, the observed radius of the Universe. This result is obtained by…
Superclusters of galaxies can be defined kinematically from local evaluations of the velocity shear tensor. The location where the smallest eigenvalue of the shear is positive and maximal defines the center of a basin of attraction.…