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It's a fact that our planet's location from our parent star (among other factors) is of crucial importance to the existence of life. But can our position in the galaxy be considered a factor when considering potential planets to carry life?

In any given position in the galaxy for instance there are distinct radiation levels, distinct gravitational effects, space-time, etc. These factors could contribute to the existence of life on earth or even its continuity, wouldn't they?

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Certain regions of the galaxy are more favourable for life, others less. Life takes some time to develop, and it needs chemical elements heavier than helium, e.g. carbon or silicon.

To get sufficient time to develop, the solar system must not be disturbed too much by neigbouring stars. Therefore inner densely populated parts of the galaxy are less suitable than the periphery we are located. (The central star of the planetary system must not be too young, as well, to allow evolution.)

Heavier chemical chemical elements are sufficiently abundant mainly in parts of the galaxy with relatively young stars (population I). This kind of stars is found mainly in the thin disk close to the galactic plane.

Very old stars tend to expand, and may eventually destroy potential life on their planets, if they are surrounded by rocky planets at all.

More discussion on a potential galactic habitable zone on Wikipedia.

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Yes, in the sense that there are some places that it would not be great to be - for instance if we were near the galactic centre we would risk being gobbled up by the super-massive black hole that is likely to exist there and so on. But spatially most of the galaxy is much like where we are, so it is not as though we are in a particularly special place.

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The chance of the host star being part of a Binary is also of significance, since the majority of stars in our galaxy form one member of a binary or higher order stellar system. Research has hinted that the number of planets in binary systems is larger due to gravitational perturbations collecting the dust disc quicker which could in turn lead to a higher chance of a planet landing in the habitable zone.

We are still unsure of the effect of a stellar companion on the chances for life on a planet. It could be detrimental by perturbing the orbit of any planets around either star, leading to it moving in and out of the habitable zone (not good for creating steady conditions for life).

The chance of a star being in a binary system increases as the number density of stars increases; areas such as the Bulge at the centre of a disc galaxy, or in elliptical galaxies. The disc would have a lower density of binaries.

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