Redshift and Distance:
* Redshift measures how much the light from a distant object has been stretched due to the expansion of the universe. A higher redshift means the object is further away and the universe has expanded more during the time the light has been traveling.
* Distance is not directly proportional to redshift. The relationship is complex and depends on the expansion history of the universe.
Factors Complicating the Relationship:
* The Universe is Expanding: The expansion of the universe is not constant; it was faster in the past. This means a redshift of 0.6 could correspond to a slightly different distance than it would have in a universe with constant expansion.
* Cosmological Models: Astronomers use models of the universe to convert redshift to distance. These models are based on our understanding of the universe's composition (dark energy, dark matter, etc.) and can have slight variations.
The Approximation:
While a redshift of 0.6 does generally correspond to a light travel distance of around 6 billion years, it's important to note:
* This is an approximation. More accurate calculations would take into account the factors mentioned above.
* The universe is still expanding. The distance to that object is increasing even as we speak.
In conclusion:
While a redshift of 0.6 roughly translates to light traveling for about 6 billion years, it's crucial to remember that this is a simplified view. Accurate distance measurements require more sophisticated cosmological calculations.
