NOTICE: help.openstreetmap.org is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum

I am interested in compiling places suitable for stargazing in the UK.

It is currently noted as a custom map in Google Maps.

I collected this info myself from events announcements, my own experience, and public news (such as the launch of a new observatory).

  1. Would this be suitable for adding to OSM?
  2. What is the best way, is it just tagging existing POI if available, or creating a new category of POI for this activity (is that even possible?)

Thank you.

asked 22 Nov '12, 09:54

ismangil's gravatar image

ismangil
31114
accept rate: 0%


Hummm I don't think that kind of info would be suitable for OSM, even though it is tempting.

My rationale is that it is a quantitative and continuous property. In other words, every place on Earth could be attributed a "dark sky rating" and we'd have to cover the whole map. This is the same problem as elevation data; we keep it out of OSM because it is not technically a good place to put that kind of data (as interesting and free as it may be).

You could counter by saying that you only map the best spots, but that's still a relative value, and the best stargazing spots in UK are actually pretty bad compared to other (dryer, less populated) areas of the world.

That said, if one of the spot is actually signposted / advertised on the ground, this is another story. In that case, I'd get inspiration from the viewpoint tag.

permanent link

answered 22 Nov '12, 10:52

Vincent%20de%20Phily's gravatar image

Vincent de P... ♦
17.3k18152249
accept rate: 19%

I understand. I suppose official sites like observatories are acceptable as a POI.

(22 Nov '12, 20:20) ismangil
1

Concerning elevation, I think this is wrong.

First, according to tagwatch there are around 1.8 million entries of elevation in the database, often attachted to otherwise relevant nodes. They do no harm.

Second, most geodata could be interpreted in several ways. Streets have a continuous curving, yet we map it as line string with vertices.

(23 Nov '12, 07:20) Roland Olbricht
1

Yes, "official" sites or indeed anything that is observably true can be tagged. If there's a pole in the ground with a sign saying there's a good star view from here - it's fine to tag the fact that there's a pole because it is undeniably there. It's just the subjective bits ("good view of Alpha Centauri from here at times") that are problematic.

(23 Nov '12, 11:15) Frederik Ramm ♦

Hopefully most elevations are on specific points such as on mountain/hill peaks, mountain passes and possibly spot depths.

(24 Nov '12, 18:39) robbieonsea

Yes, this fits into OSM, although it is sensitive to the rule that all data shall be verifiable on the ground.

Please be bold in adding places. You will get a couple of complaints about new tags but that is common and no reason to worry. Hand-added data never amounts to significant data load, but people often confuse it with the (mostly useless) data created by automated scripts (bots) that often amounts to magnitudes of more data than all hand edits.

The best way to go is

  1. invent a dedicated tag such that no collision happens. "dark_sky_visibility=Milky Way" would work for example. "source:dark_sky_visibility" does help to support verifiability.

  2. Tag a couple of places by adding the tag to existing elements (a field, a place node or so). 20 or 30 places suffice already.

  3. Set up a custom map showing these places. An easy way is to modify one of these examples.

  4. Announce the wohle thing on the mailing list osm-talk. This makes the tag visible for everybody without the risk that discussion trolls put the whole concept in question.

Please be careful with the wiki. There is a process called "Proposal" which was meant as a dicussion platform but turned out to be mostly an extremely bureaucratic impediment. A lot of "proposals" deferred the documentation of a tag by more than half a year. So it may be a good idea to document the tag only after the annoucement on the mailing list. The same applies to the tagging mailing list, which is more about minuscule differences in interpreation of a tag meaning than the introduction of new types of data.

permanent link

answered 23 Nov '12, 07:48

Roland%20Olbricht's gravatar image

Roland Olbricht
6.7k36489
accept rate: 36%

Imho it would be more efficient to render a light pollution map based on the existence of places (villages, cities), the tag lit=yes and some wizardry (considering amongst others number of inhabitants, size of the places) to determine the distance in which the light pollution is small enough to allow a good view to the dark sky.
A simple light map exists already: http://lightmap.uni-hd.de/
(btw: there is also a proposal to tag shades which looks to me the same category like the issue above )

permanent link

answered 24 Nov '12, 00:01

malenki's gravatar image

malenki
4.7k24683
accept rate: 6%

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here

By RSS:

Answers

Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text](http://url.com/ "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:

×181

question asked: 22 Nov '12, 09:54

question was seen: 4,261 times

last updated: 24 Nov '12, 18:39

NOTICE: help.openstreetmap.org is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum