Friday 19 August 2016

Selecting a site for Astronomy Purposes

Hi everyone,

No matter your niche within astronomy, we all want to find the best location that is most favourable for our pursuit.

While we take it as a given that we want a dark sky, just a clear open paddock is not necessarily the best location.  In many instances, that clear paddock is actually the worst location we could use when a significantly better site could be just a little further along.  All that may be missing is just knowing what the optimal site conditions are in order to identify the better locations.

Selecting the best location can also have a major impact on the bane of all astronomers - dew.  A good location can just about see dew eliminated as an issue instead of being unavoidable.  And of course the elimination of dew as a problem significantly reduces the complications associated with needing to deal with it.

But site selection is also a case of compromise.  And the optimal site location may not be attainable.  Yet by being aware of what the optimal is, then the best possible compromise location can be found.

And above everything else, the site needs to be safe.

You will find my article on site selection in the new page titled "Selecting a site for Astronomy Purposes".

Clear skies,



  1. This comment is based on my location in the United States. If you're "down under", substitute North for South!

    I'm on the road as a truck driver and carry an 8" dob with me. I'm always on the lookout for nice dark observation sites in the Western U.S. where I can safely and legally park my truck.

    One factor I always consider is an unobstructed view of the southern horizon. Those objects along the ecliptic disappear in the West before you know it. The closer to the horizon, the sooner they are gone. Stuff in the East is not a problem, just wait around a few hours and they will get higher in the sky. Circumpolar objects are always there. If they're not high enough above the northern horizon, come back in a couple of months. But those gems along the South fade quickly.

  2. Hi Bill.

    Yes, chasing those horizon grazing objects is always a tease. The window of opportunity is always tight. This is why I find the humble, old planisphere such a powerful too. It lets me know when the "season" for a particular object begins and ends, and the optimal times during that season.

    It is sometimes worthwhile finding a particular location that is out of the ordinary even as a one-off in order to get that clear horizon for that particular object.

    For me, the Airfield site is a great "everyday" site with all the comfort advantages that it has. But its northern horizon is not great. The Victoria Falls site is different in that respect - it has an exceptionally clear horizon ALL around, but it is much more exposed and has none of the creature comforts of the Airfield.

    Having choice in sites is another aspect that hadn't occurred to me at the time of writing up this article. Thanks Bill!