Related papers: Lessons from the Milky Way: the Kapteyn Universe
Antonie (Anton) Pannekoek (1873-1960) is remembered as one of the initiators of the field of stellar atmospheres. A second part of his research concerned Galactic astronomy. He was convinced that the sidereal system was built up of clouds…
Cornelis Easton (1864-1929) became a journalist and newspaper editor. During most of his career he was active as an amateur astronomer and contributed important papers in international astronomical journals This concerned three areas. The…
In the century since Einstein's anno mirabilis of 1905, our concept of the Universe has expanded from Kapteyn's flattened disk of stars only 10 kpc across to an observed horizon about 30 Gpc across that is only a tiny fraction of an…
In this contribution I discuss the Kapteyn Astronomical Laboratory during the period of Pieter Johannes van Rhijn's directorate, which lasted from 1921 to 1957. It had developed under the founder Jacobus Cornelius Kapteyn into one of the…
The selective light absorption in space has been raised in astronomical literature. The substance producing the absorption must have some mass; thus the question is how large it is. We develop a dynamical model of the Milky Way system,…
The star formation rate history of the Milky Way is derived using the chromospheric age distribution for 552 stars in the solar neighborhood. The stars sample birthsites distributed over a very large range of distances because of orbital…
The asymmetry in the large-scale distribution of the directions towards spiral galaxies rotate has been observed by multiple telescopes, all show a consistent asymmetry in the distribution of galaxy spin directions as observed from Earth.…
Johannes Kepler described the Copernican universe as consisting of a central, small, brilliant sun with its planetary system, all surrounded by giant stars. These stars were far larger than, and much dimmer than, the sun -- his De Stella…
The "plane of satellites problem" describes the arrangement of the Milky Way's 11 brightest satellite galaxies in a remarkably thin plane, possibly supported by rotation. This is in apparent contradiction to the standard cosmological model,…
Thin halo star streams originate from the evaporation of globular clusters and therefore provide information about the early epoch globular cluster population. The observed tidal tails from halo globular clusters in the Milky Way are much…
``One could imagine that as a result of enormously extended astronomical experience, the entire universe consists of countless identical copies of our Milky Way, that the infinite space can be partitioned into cubes each containing an…
Almost 80 years have passed since Trumpler's analysis of the Galactic open cluster system laid one of the main foundations for understanding the nature and structure of the Milky Way. Since then, the open cluster system has been recognised…
We review observational evidence bearing on the formation of a prototypical large spiral galaxy, the Milky Way. New ground- and space-based studies of globular star clusters and dwarf spheroidal galaxies provide a wealth of information to…
In 1785 astronomer William Herschel mapped out the shape of the Milky Way star system using measurements he called "star-gages." Herschel's star-gage method is described in detail, with particular attention given to the assumptions on which…
Recent observations have shown that the majority of the Andromeda galaxy's satellites are aligned in a thin plane. On the theoretical side it has been proposed that galaxies acquire their gas via cold streams. In addition, numerical…
After a brief introduction to the sixteenth and seventeenth century views of the Universe and the nineteenth century paradox of Olbers, we start the history of the cosmic expansion with Hubble's epochal discovery of the recession velocities…
Anton Pannekoek (1873-1960) was both an influential Marxist and an innovative astronomer. This paper will analyse the various innovative methods that he developed to represent the visual aspect of the Milky Way and the statistical…
The geocentric universe, in its most developed form as set out by Ptolemy, was a remarkably successful and coherent theory. It did not, however, specify the order of the planets, that is, which was closer to Earth and which farther away.…
Over the last decades, observations with increasing quality have revolutionized our understanding of the general properties of the Universe. Questions posed for millenia by mankind about the origin, evolution and structure of the cosmos…
Stellar activity may induce Doppler variability at the level of a few m/s which can then be confused by the Doppler signal of an exoplanet orbiting the star. To first order, linear correlations between radial velocity measurements and…