LambdaCDM and Galaxies

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A poster about our universe, in particular the LambdaCDM cosmology and galaxies. Evolution of the universe via hierarchical clustering can be tracked from the primordial photon-baryonic fluid at the age of ~ 379 kyr (center left) through towards first stars, galaxies, galaxy clusters and Laniakea. Evidence for dark matter and dark energy, Λ, is reviewed. Additional information is provided on the distance ladder—ways astronomers use to measure distances—and the AGN Paradigm that explains all active galaxies depending on the line of sight.

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Stellar-Mass Objects

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A poster with the most common objects you will find in a galaxy, most are of stellar mass. Evolution can be tracked from left to right. Start at the interstellar dust and gas (center left) and progress right-ward, as the nebula evolves into a young stellar object, becomes a star and evolves on the main sequence. General scenarios of stellar evolution are shown depending on the mass, with end products being brown and red dwarfs, neutron stars and black holes, supernova explosions, and white dwarfs.

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Supermassive Black Holes

Supermassive black holes (SMBHs) represent an important aspect of galaxy evolution theory that remains at the frontier of modern research. Like their stellar-mass versions, SMBHs have Schwarzschild radii, prevent light from escaping their event horizons and form accretion disks (ADs). Understanding SMBH origin and growth is of central importance in extragalactic astron- omy due to their connection with the evolution of galaxies (Kelly et al. 2010).

Essay: Supermassive Black Holes

Migrating Planets

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Among the pioneers of the idea of swirling vortices of gas being responsible for the formation of the solar system was Descartes (1644). In his treatise, he speculated that God sent clouds adrift which changed into comets and planets. Although lacking scientific detail, parallels can be observed with nebular hypotheses pro- posed almost a century later by Swedenborg (1734) and, later, Kant (1755) using Newtonian principles. The first to develop a model of the rotating gaseous nebula collapsing and evolving into a planetary system was, however, Laplace (1796) who did it in a rigorous mathematical way. Although recent history of cosmological theories includes many contrasting alternatives (Buffon 1745; Chamberlin 1901; Jeans 1928; Jeffreys 1929; Whipple 1948), scientific consensus appears to be emerging on how the solar system evolved into its current state.

Essay: Migrating Planets

Liquid Water on Mars

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Geomorphological, mineralogical and other evidence of the conditions favoring the existence of water on Mars in liquid phase is reviewed. This includes signatures of past and, possibly, present aqueous environments, such as the northern ocean, lacustrine environments, sedimentary and thermokarst landforms, glacial activity and water erosion features. Reviewed also are hydrous weathering processes, observed on surface remotely and also via analysis of Martian meteorites. Chemistry of Martian water is discussed: the triple point, salts and brines, as well as undercooled liquid interfacial and solid-state greenhouse effect melted waters that may still be present on Mars. Current understanding of the evolution of Martian hydrosphere over geological timescales is presented from early period to the present time, along with the discussion of alternative interpretations and possibilities of dry and wet Mars extremes.

Essay: Liquid Water on Mars