View/Open - University of Hertfordshire
... The measurement of radial velocity has played a pivotal role in the analysis and understanding of the cosmos. It provides a signature of the motion of objects tracing the distribution of matter and gravitational potential. The discovery of an expanding universe by Hubble [1925] was made from radial ...
... The measurement of radial velocity has played a pivotal role in the analysis and understanding of the cosmos. It provides a signature of the motion of objects tracing the distribution of matter and gravitational potential. The discovery of an expanding universe by Hubble [1925] was made from radial ...
The Green Valley is a Red Herring: Galaxy Zoo reveals two
... Ever since the discovery of the bimodality in galaxy colour in the galaxy colour-magnitude and colour-mass diagrams from largescale surveys (Strateva et al. 2001; Baldry et al. 2004, 2006), the colour space between the two main populations — the green valley — has been viewed as the crossroads of ga ...
... Ever since the discovery of the bimodality in galaxy colour in the galaxy colour-magnitude and colour-mass diagrams from largescale surveys (Strateva et al. 2001; Baldry et al. 2004, 2006), the colour space between the two main populations — the green valley — has been viewed as the crossroads of ga ...
- SkyServer
... COSMIC_RAY) – Spectra available – In main galaxy sample (primTarget = GALAXY but not GALAXY_RED) ...
... COSMIC_RAY) – Spectra available – In main galaxy sample (primTarget = GALAXY but not GALAXY_RED) ...
MUSE three-dimensional spectroscopy and kinematics of the
... 0.61 M yr−1 . Both galaxies show rotational velocity gradients in Hα and other lines, with the interaction being prograde–prograde. The SE–NW velocity gradient of the AGN host is misaligned from the E–W radio axis, but aligned with a previously discovered central ultraviolet source, and a factor of ...
... 0.61 M yr−1 . Both galaxies show rotational velocity gradients in Hα and other lines, with the interaction being prograde–prograde. The SE–NW velocity gradient of the AGN host is misaligned from the E–W radio axis, but aligned with a previously discovered central ultraviolet source, and a factor of ...
Observational motivation for Dark Matter
... All evidence for DM is eventually based on gravitational effect on other objects (except BBN) It is appealing to find a “correction” to Newton/GR gravity that will fix this need There are quite a few attempts, most suffer from all kind of problems (consistency, observations) ...
... All evidence for DM is eventually based on gravitational effect on other objects (except BBN) It is appealing to find a “correction” to Newton/GR gravity that will fix this need There are quite a few attempts, most suffer from all kind of problems (consistency, observations) ...
The (galaxy-wide) IMF in giant elliptical galaxies: from top to bottom
... Kroupa & Baumgardt 2009; Dabringhausen et al. 2012). These pieces of seemingly contradicting evidence could, instead, suggest that the evolution of the IMF is much more complex, with a strong ...
... Kroupa & Baumgardt 2009; Dabringhausen et al. 2012). These pieces of seemingly contradicting evidence could, instead, suggest that the evolution of the IMF is much more complex, with a strong ...
Weak gravitational lensing
While the presence of any mass bends the path of light passing near it, this effect rarely produces the giant arcs and multiple images associated with strong gravitational lensing. Most lines of sight in the universe are thoroughly in the weak lensing regime, in which the deflection is impossible to detect in a single background source. However, even in these cases, the presence of the foreground mass can be detected, by way of a systematic alignment of background sources around the lensing mass. Weak gravitational lensing is thus an intrinsically statistical measurement, but it provides a way to measure the masses of astronomical objects without requiring assumptions about their composition or dynamical state.