Astronomy vs Cosmology: Understanding the Differences Explained

[pixel01]

Hi all,
This question may seem innocent, but I can't see a clear boundary between the two. Who could explain it please.
(as short as possible).

 

[Wallace]

There is no clear boundary between the two, as they are closely related. However, the distinction is that astronomy generally refers to the act of observing things (be that stars, galaxies or whatever) which, coupled with astrophysics, aims to understand those things for their own sake. The aim is to learn about the stars, galaxies or whatever.

On the other hand, the aim of cosmology is to understand broader questions about the Universe, such as its origin, underlying physical laws etc. Cosmology requires astronomy and astrophysics in order to get data to compare to cosmological models, but for a pure cosmologist these are just tools to achieve the aims of cosmology, rather than being the goal in their own right.

As I said though, the boundaries are not clear cut, but that is the basic distinction.

 

[pixel01]

Thanks Wallace, ít's clear (cut) now

 

[mgb_phys]

I would have said that astronomy is the overall subject and cosmology is the specialist branch of the formation and structure of the universe.

 

[Wallace]

Cosmology does not, in principle, imply that you are doing anything related to observing stars, galaxies etc. In modern cosmology these tools are used because we think that we can learn something about the origin and workings of the Universe by doing so. That wasn't inevitable though, and cosmology as a thought process existed before it was linked with astronomy.

It is also not inevitable that cosmology with remain so closely linked to astronomy. If (and it is a very big if) we detect and are able to study dark matter, dark energy etc in the laboratory then this may prove a better way forward for cosmology than learning their properties via astronomical means.