Denmark the 22 proposals have been agreed upon by a parliamentary majority. Denmark shares strong cultural and historic ties with its Scandinavian neighbours Sweden and Norway. It has historically been one of the most socially progressive cultures in the world. In 1969, Denmark was the first country to legalise pornography, and in 2012, Denmark replaced its "registered partnership" laws, which it had been the first country to introduce in 1989, with gender-neutral marriage. Modesty and social equality are important parts of Danish culture. The astronomical discoveries of Tycho Brahe (1546–1601), Ludwig A. Colding's (1815–88) neglected articulation of the principle of conservation
Planetary and Space Science Planetary and Space Science Planetary and Space Science, published 15 times per year, is a peer-reviewed scientific journal established in 1959. It publishes original research articles along with short communications (letters). The main topic is solar system processes which encompasses multiple areas of the natural sciences. Numerical simulations of solar system processes are also conducted at ground-based facilities or on-board space platforms. The editor-in-chief is Angelo Pio Rossi (Jacobs University). It is published by Elsevier. Research that involves planetary and space sciences involves many disciplines, which is reflected by the scope of the journal. Celestial mechanics is part of these