A Redshift data on stars the same distance from earth

AI Thread Summary
The discussion focuses on the lack of hard research data demonstrating that stars at the same distance from Earth show no detectable redshift differences, which relates to the question of whether the universe has a preferred direction of expansion. It is noted that individual stars within our galaxy do not exhibit expansion due to being bound objects, while nearby galaxies' red- or blue-shifts are primarily influenced by local motions. Cosmological redshift becomes significant only at greater distances, where individual stars cannot be distinguished. For obtaining data on galactic redshifts, the SIMBAD database and other resources are recommended for further research. The conversation emphasizes the need for average measurements across galaxies to understand redshift behavior.
Jim Hasty
Messages
33
Reaction score
8
Can anyone in the cosmology community direct me to hard research data that specifically demonstrates: there is no detectable redshift difference in stars that are the same distance from the Earth but in all different directions. This is of course related to 'does the universe have a preferred direction of expansion', the literature of which I find on google does not provide data, just brief conclusions. Thanks.
 
Space news on Phys.org
Individual stars tend to be visible within our galaxy but there is no expansion of such bound objects. Nearby galaxies have the majority of their red- or blue-shift determined by local motions. It's only when you get to more distant galaxies that cosmological redshift starts to dominate, and by then you cannot make out individual stars. Again their motion would be principally that within the galaxy, what you need to do is measure the average for the whole galaxy.

For hard data on galactic redshifts, I would suggest you start with the SIMBAD database but there are others. Once you know what details you want, you can get more specific advice on search criteria.
 
  • Like
Likes Jim Hasty
GeorgeDishman said:
Individual stars tend to be visible within our galaxy but there is no expansion of such bound objects. Nearby galaxies have the majority of their red- or blue-shift determined by local motions. It's only when you get to more distant galaxies that cosmological redshift starts to dominate, and by then you cannot make out individual stars. Again their motion would be principally that within the galaxy, what you need to do is measure the average for the whole galaxy.

For hard data on galactic redshifts, I would suggest you start with the SIMBAD database but there are others. Once you know what details you want, you can get more specific advice on search criteria.
Thank you so much, George. This is incredible and helpful.
 
Abstract The Event Horizon Telescope (EHT) has significantly advanced our ability to study black holes, achieving unprecedented spatial resolution and revealing horizon-scale structures. Notably, these observations feature a distinctive dark shadow—primarily arising from faint jet emissions—surrounded by a bright photon ring. Anticipated upgrades of the EHT promise substantial improvements in dynamic range, enabling deeper exploration of low-background regions, particularly the inner shadow...
what is the current status of the field for quantum cosmology, are there any observations that support any theory of quantum cosmology? is it just cosmology during the Planck era or does it extend past the Planck era. what are the leading candidates into research into quantum cosmology and which physics departments research it? how much respect does loop quantum cosmology has compared to string cosmology with actual cosmologists?
Back
Top