1. Measuring Light Pollution in Montsec: a protected area
Direcció General de Qualitat Ambiental
Servei per a la Prevenció de la
Contaminació Acústica i Lluminosa
Measuring Light Pollution in Montsec: a protected area
Salvador J. Ribas
on behalf of Parc Astronomic Montsec &
Servei Català per la Prevenció de
la Cont. Acústica i Lluminosa

2. Index Montsec: a natural area with an astronomical park
Protection of Montsec sky ( )
New Measurements ( ??)
Results and Conclusions
Something More…

3. Observatori Astronòmic
Where is Montsec ?
Iberian Peninsula
Centre d’Observació
de l’Univers
Observatori Astronòmic
del Montsec
Ager valley & Montsec mountains
Catalonia region

4. Montsec: a natural area
Montsec is a calcareous mountain range more than 40 kilometers long, covering an area of 18,696 hectares divided between Aragon and Catalonia. The Catalan side covers various municipalities in the counties of Pallars Jussà and La Noguera.
The mountain range is divided by two rivers with wonderful canyons in three parts: two in Catalonia and one in Aragon.
This was a depressed area with a constant reduction of the inhabitants number. But with a huge number of interesting things: history, biology, geology and astronomy.

5. Parc Astronòmic Montsec
Since 90’s, this area was used for amateur astronomers and they proposed to create an Astronomical Park. Parc Astronomic Montsec (PAM) was officially opened in
Objectives of PAM:
To offer actual infrastructures focused to research and communicate astronomy (main topic) and natural environment (geology, fauna and flora).
These materials will allow to accomplish educational objectives in several levels (from primary education to university students) and outreach activities to general public.
To increase scientific touristic activities that will allow to maintain regular affluence of public to the area
Using… particular weather conditions, a wonderful environment and the darkest sky of Catalonia and of the best of Europe.

6. Parc Astronòmic Montsec
Observatori Astronòmic del Montsec (OAdM)
Centre d’Observació de l’Univers (COU)

7. Light pollution in the area
This is the darkest sky of the whole Catalonia.
Ground-based studies show that Montsec skies are 80 times darker than the Barcelona sky.
Montsec skies are considered free of light pollution (natural sky) and are specially protected by Light pollution Catalonian law.
For many years only the PAM site testing measures were available for study LP problem.
Cinzano et al 2000

8. Aquests resultats mostren que la zona de la Serra del Montsec és molt bona en quan a contaminació lumínica. Per aquest motiu, entre d’altres requisits necessaris, s’ha decidit construir-hi un observatori, l’Observatori Astronòmic de Catalunuya (OAM).
Les mesures des del lloc on es farà l’observatori permeten detectar, lleugerament, la llum que prové de Barcelona (a uns 200 Km) i, més clarament, la de Lleida (a uns 50 Km) i Balaguer (a uns 25 Km).
També s’ha seguit mesurant el cel de Bcn.

9. Protection of Montsec Sky
Actions of the Government of Catalonia:
Mid 90’s started the project to build Parc Astronòmic Montsec.
At same time public and private institutions encouraged Government to prepare the Light Pollution Law.
In 2001, Law 6/2001 (31st May) was approved by Parliament of Catalonia. It was the first regional law in Spain.
: First detailed series of measurements in Catalonia
Night sky above PAM domes

10. The Sky of Montsec… THE NATURAL SKY !!!
Old Measures ( )
The Sky of Montsec… THE NATURAL SKY !!!
Montsec mountains (OAdM) :
V ~ (with peaks of 22.1)
Castell de Mur V ~ 21.3 (1.6 times brighter)
Port d’Àger V ~ 21.2 (1.7 times brighter)
Fontllonga V ~ 20.9 (2.3 times brighter)
Isona V ~ (3 times brighter)
Balaguer V ~ 20.0 (5.2 times brighter)
Barcelona (Faculty of Physics)
V ~ 17.0 (83 times brighter)

11. Protection of Montsec Sky
Decree 82/2005, with the regularions related to Law 6/2001. It defines..
Observatori Astronòmic del Montsec (reference point) + municipalities in the surrounding with maximum protection (E1)
, en el Montsec:
- Lighting adaptation to Law 6/2001:
€ by Government of Catalonia
- Panels in some roads
- Signposting in the surroundings of PAM
- Public communication of this problem.
Protect the dark sky. Remember use only dipped headlights.

12. Protection of Montsec Sky
19th December The protection map of Catalonia was approved
Distribution of Areas E1
34,18% E2
60,25% E3
5,54% E4
0,02%

13. A typical problem…

14. But almost solved…

15. Protection of Montsec Sky
The Decree was cancelled after a lot of problems. Now the modified Decree is in preparation.
In 2012 a new campaign of measurements started in cooperation between Catalonian Service against LP and Parc Astronòmic Montsec.
In 2013 a new resolution was approved to protect Montsec :
The Observatori Astronòmic del Montsec is the reference point
The influence area are considered E1 zones
New light parameters are defined for these E1 zones.
The light parameters for Montsec are:
Superior hemisphere flux is limited to a maximum of 1%
Sodium lamps and Ambar LED are the only accepted systems.
Ambar LED only can have 1% of emission below 500nm and no peak in 440nm.
Conclusion:
Montsec area is a protected area with the maximum protection of Catalonian law. Is it enough?

17. New Measurements ( )
The first method is SQM photometry with SQM-LU and GPS (RoadRunner configuration). This system was designed by Sociedad Malagueña de Astronomía and it is available for use.
We defined 11 routes around Montsec to have measures in all the area. These routes could be repeated every month, year, …

18. New Measurements ( )
The second method is astronomical photometry with an all sky camera. We used the ASTMON Lite system developed by Itec Astronomica S.L. This is a portable version of the system installed in Calar Alto Observatory or National Park of Doñana.
The equipment was only available in the last months of this campaign, so we select 7 points for its test and first scientific data.

19. Results and Conclusions
METHODOLOGY:
SQM-Road Runner technique showed as the best option for a global study of an extended area, but it is necessary to define good route to cover it.
The integration of SQM with GPS in a moving system give us the opportunity to take a lot of measurements and to repeat them for comparison
It is very important to have a good knowledge of the area to prevent effects of vegetation, canyons, etc in the measures.
ASTMON technique showed as the best for the detection of light emission areas because we obtain an all-sky map of the brightness.
Using a fisheye lens is more efficient than the old techniques using telescopes. ASTMON give us a very accurate map in few minutes.
Using all-sky techniques allow us to detect the emission areas and the altitude of their effect in the sky.

20. Results and Conclusions
EVALUATION OF THE SKY:
Confirm the sky of Montsec as one of the best skies in Southern Europe. Almost all the measurements outside villages are better than mag in the zenith position.
Detection of excellent areas with results better than mag in the zenith. These areas are placed in the mountains and not so close to the towns.
Only few municipalities inside the area create notable light effects outside the urban area. These are Balaguer, Tremp, Ponts and Artesa de Segre.

21. Results and Conclusions
Balaguer 20.0 mag
OAdM 21.6 mag
Direction analysis showed there are not notable influences of municipalities inside the Montsec area. Only border and external municipalities’ effects have been detected.
Large distances effects have been detected from Lleida (50km far), Barcelona and surroundings (more than 100km), Zaragoza (more than 100km) and Barbastro and Monzón (50 km). The most important effects are from Lleida. These effects have been detected in measurements made inside Balaguer city.
The comparison of previous data showed us the central parts of the area have similar results. In some places now we obtain better results than in due to the lamp replacement programs made in the last decade.

23. Something More… Starlight!!
We used this data for the process of Starlight Certification.
24 municipalities were approved as Starlight Touristic Destination and 11 were Starlight Reserve too.

24. Thanks for your attention!!
More information:
Direcció General de Qualitat Ambiental
Servei per a la Prevenció de la
Contaminació Acústica i Lluminosa