Alentejo Remote Observatory

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Astro Alentejo Remote Observatory (AstroARO) has chosen the Alentejo region in Southern Portugal to install its first observatory.

It is therefore precisely located in the area labelled “Dark Sky Alqueva”. It is a protected and internationally certified area, registered as a Dark Sky Reserve or “Starlight Tourism Destination”. This certification was awarded by UNESCO, the STARLIGHT Foundation and the World Tourism Organization.
As this place has been recognized as a preferential destination for observing the sky, the municipalities surrounding Lake Alqueva – Alandroal, Reguengos de Monsaraz, Portel, Mourão, Moura and Barrancos – have joined forces to preserve this special feature and, as a result, reduce public lighting at night as much as possible, so that everyone can enjoy this phenomenon of nature to the fullest.

Minimum certification criteria :
-Absence of clouds >50% with cloudless nights.

The Dark Sky Alqueva Reserve has an average of 240 clean nights, i.e. without the presence of clouds.
SQM >21 mag/dry arc
The Dark Sky Alqueva Reserve records in some places measurements of 21.60 mag/arcsec.
Transparency: mag 6
Seeing maxi 1,5 ”

We have done a lot of research to find the best compromise to get away from the cities and towns.Light pollution is therefore limited to the maximum, especially as the air is dry.

The observatories developed by ARO are of the sliding roof type. Whatever the position of the telescopes, the roof can be closed, without risk of damage to the astronomical equipment, for obvious safety reasons. The observatories are modular and can accommodate 4 to 8 telescopes.

They are designed in mechanically welded construction and are adjustable in height to cope with differences in ground level.

A 100mm insulation of “styrodur” material has been installed on the entire structure, including the floor.

The roof is equipped with the Cloudwatcher security system: This provides real-time (every minute) data on cloud cover, temperature, wind, light and rain. As soon as clouds or bad cloud cover arrives, the Cloudwatcher delivers the information to the mounts so that they move to the Park position and stop the image acquisition. The roof closes at the same time, since whatever the position of the telescopes, it is possible to close the roof.

The telescope extension is provided and calculated by AstroARO.

An All Sky camera can be consulted at any time, and records the state of the sky.

A non-infrared interior camera allows you to see the proper functioning of your frames and the condition of your set up.


Camera AllSky Occulus
Vision du ciel

Electrical Network :

Panneau Solaire Monocristallin 320W
Onduleur Chargeur Victron Multiplus 2
Batterie OPZV 2V 686Ah

The electrical network is not distributed to the observatory and in a periphery of about 3 kms, which guarantees us no light pollution in the vicinity.

The electrical supply is thus ensured by solar panels and batteries of very high quality, of German manufacture (monocrystalline solar panels and Opzv 2Volt batteries with remote charge controller). The power supply is provided in 220Volts.

An emergency generator with automatic start is also provided.

High Speed Internet :

-Satellite internet connection.

-Downlink 30Mbps, uplink 6Mbps

-Direct access to your local netwo

Pricing :

Promotional price offer for Telescope (as of 01/01/20) up to the 4th Set Up

Diametre Du TelescopePrix Mensuel TTC (dont TVA 23%)
Hors Assurance, Contrat 1 An
0″ , 0mm < Diametre Ø <= 8" , 204mm280.00€
8″ , 204mm < Diametre Ø <= 11" , 280mm292.00€
11″ , 280mm < Diametre Ø <= 15" , 381mm324.00€
15″ , 381mm < Diametre Ø <= 19" , 483mm393.00€
19″ , 483mm < Diametre Ø <= 24" , 609mm514.00€

Promotional price offer for Telescope (Lunette) (as of 01/01/20) .If two telescopes are used, the diameters are added together.

<=106 mm <= 530 mm 280€
<= 130 mm <=1000 mm 292€
> 130 mm > 1000 mm 324€

Supervision and Works :

The site is 10 minutes from the tarred secondary roads. We reach it by a 4 km track, which can be driven by passenger vehicles. It ends at the owner’s residence.

The daily surveillance is ensured by the owner of the premises. He lives near the observatory and has guard dogs.

Cameras of surveillance are installed and can detect any anomaly, near the observatory. They operate 24 hours a day.

An alarm is triggered when there is an intrusion inside.

The site will be fully protected by a high wire fence.

First level maintenance is provided by the owner, who has been passionate about Astronomy since his childhood… The minimal work known as first level maintenance will be provided by the owner, usually free of charge or according to the frequency and complexity on a basis of 10€ per hour including tax.

Reception and Tourism :

The Alentejo has magnificent views, wooded hills, vineyards, cork oaks and olive trees as far as the eye can see. It is an authentic region, where people take the time to live, far away from mass tourism. Rich in prehistoric remains (Dolmens and Cromlechs), Roman ruins, each locality has its own castle which dominates and evokes the wars and conquests of the past. Evora, listed as a UNESCO World Heritage Site, Monsaraz, one of the most picturesque villages in the Alentejo, is a visit not to be missed. The lake of Alqueva is a famous fishing spot.( see Contacts/Links )

You can therefore take advantage of the installation of your telescope to visit the surrounding area with your friends or family.

Accommodation can be provided on site. The owner can provide two furnished rooms with separate bathrooms.

 You can take advantage of the swimming pool to cool down in the summer.

Nombre De LogementTarif TTC
1 Chambre avec Sdb-Winter:50€/day+breakfast-
2 Chambres avec Sdb

For a larger number of people, we have negotiated preferential pricing in several homes in the region. ( See Contacts/Links )