OBSERVATORIO DEL ROQUE DE LOS MUCHACHOS

This observatory is a must, a must visit. First of all for the site itself, magnificent, with a breathtaking view of the Caldera de Taburiente National Park and its vast crater of ten kilometres in diameter visible 900 metres below. Some of the viewpoints are accessible from the road leading up to the observatory (Los Andenes viewpoint). There are also hiking trails from the top of the mountain, above the last domes of the observatory, that offer other possibilities for the inveterate hiker. Located at an altitude of 2,400 metres, this observatory consists of a dozen instruments administered by the Canary Islands Astrophysics Institute and operated by many European countries. In July 2009, the world's largest visual telescope was inaugurated here. It is located at the El Roque de los Muchachos Astrophysical Observatory, built in 1985. The very high height allows for excellent air quality. In fact, the scientists benefit from a transparent observation of the sun and the light waves coming from other galaxies. This installation is the result of an international collaboration involving many countries that have participated in one or more of the observatory's projects: Spain, the Netherlands, France, the United Kingdom, Ireland, Belgium, etc. The William Herschel Telescope was completed in 1987 and became the largest telescope in operation on European territory at the time of its inception. With a diameter of 4.20 metres, it is the result of scientific cooperation between Spain, the United Kingdom and the Netherlands. It was only surpassed by the Gran Telescopio Canarias in 2009. The Gran Telescopio Canarias is a monumental project that has made it, since the end of construction in 2009, the first European telescope and the second in the world in terms of its diameter, at 10.40 metres. It was inaugurated with great fanfare by the King of Spain himself on 24 July 2009, since, in addition to the Spaniards, the Mexicans and the Americans contributed to its financing. At present, the observatory houses the William Herschel (4.2 m diameter), Isaac Newton (2.50 m), Mercator (1.20 m), Nordic Optical Telescope (2.50 m), Telescopio Nazionale Galileo (3.58 m), a solar tower, telescopes dedicated to the observation of gamma rays.... and of course the GranTeCan (Gran Telescopio Canarias), a 10.4 m diameter "monster" among the largest in the world. These instruments are operated by various countries, including the United Kingdom, the Netherlands, Sweden, Norway, Finland, Italy... and Spain. The organized visits allow access to the main installations depending on the maintenance in progress. It is therefore necessary to obtain information beforehand. Because of the altitude, it is advisable to take warm clothes to avoid any bad surprise once there. The road to get up there is extremely winding and the journey from the coast takes about 1h15. Any bad weather on the way up is not at all a sign that it will be the same once you arrive: you may even "break through" the clouds as you wind your way up, before emerging from the sea of clouds and enjoying a beautiful blue sky. The tour, which lasts about an hour and a half, allows you to see the indoor and outdoor facilities in operation and any maintenance on the telescopes

Hawaii versus La Palma

Launched in the 1990s, the project to build a 30-metre telescope (TMT) is an international programme driven by prestigious universities, which should result in the most powerful optical and infrared telescope in the northern hemisphere, with funding of almost 1 200 million euros. After several selections, the site of the Mauna Kea volcano in Hawaii was chosen. El Roque de los Muchachos in La Palma became the second option in case the work in Hawaii did not proceed. But work in Hawaii has been halted since October 2014 following protests from the inhabitants of Mauna Kea, who felt that the installation would go against their cultural practices, as the mountain is considered sacred. There followed a lot of legal back and forth, but in July 2017, a Hawaiian judge's report recommended that the telescope be built on the agreed upon site, subject to an environmentally friendly installation. In November 2018, a new decision by the Hawaii Supreme Court validating the possibility of building the telescope in Hawaii seems to give La Palma less of a chance. However, the local Canarian authorities believe that there are still a number of data that can still delay the implementation of the project in Hawaii, and continue to prepare to host it. This was reiterated by Angel Victor Torres, president of the Canary Islands, in 2019. Specifying that the Canary Islands will continue with all the steps to facilitate the definitive installation of the large telescope (TMT) at the Roque de los Muchachos site. This is a logical move, given that this award should generate an economic contribution to the region estimated at at least 25 million euros per year. It would be the most advanced ground-based telescope in the world, ten times the size of the Hubble telescope.