Public Visits to the ALMA Operations Support Facility

Additional information about public visits and ALMA Observatory is available on the following pages:

Virtual Tour Chajnantor
Visit the ALMA OSF and AOS from your armchair with our Virtual Tours. Click on the thumbnail to experience a 360° visit.

Registering for a Guided Weekend Visit

Registration is required as there are a limited number of places on each tour.

Guided tours for tourists and the general public of the ALMA Operations Support Facility (OSF) take place on Saturdays and Sundays.

Departure from San Pedro de Atacama Return to San Pedro de Atacama
Saturday 09:00 13:00
Sunday 09:00 13:00

 

  • The guided tours are free of charge and are managed by the Joint ALMA Observatory.
  • Everyone, including minors, must register.
  • At this time we unfortunately do not have the resources to cater to tour operators.
  • To register for a visit to the ALMA Operations Support Facility (OSF), please go to the following link. To obtain an entry pass (free of charge), look for the date on which you plan to visit. If no spaces are available, you can register for the waiting list. Based on the previous visits, we know that not everyone who registers actually shows up. Therefore, if you are on the waiting list, we recommend that you come to the bus departure location in San Pedro de Atacama at 8:45 am on the day you selected to see if any space is available on the bus.
  • For safety reasons, the Array Operation Site (AOS) on the Chajnantor plateau, at 5000 metres above sea level (where the ALMA antennas are) is not open to visitors.
  • For safety reasons, children under 5 years are not allowed to visit the observatory.

Transportation from San Pedro de Atacama

  • The ALMA Observatory offers transport to tourists from San Pedro de Atacama located 35 kilometres from the ALMA Operations Support Facility. 
  • Prior registration is mandatory.
  • The guided tour starts with a bus pick-up from San Pedro de Atacama at 9:00 am. The ALMA bus leaves from Tumisa Street, close to the corner of Pedro de Valdivia Ave. (see the red spot on this map). This is close to the entrance to the artisan fair called “Pueblo de los Artesanos” and near the San Pedro de Atacama bus terminal.
  • You should arrive at least 15 minutes before the tour start time.
  • Only registered passengers who have received confirmation will be allowed on the bus. All passengers must carry some identification with them.
  • Visitors with special needs and/or disabilities should use their own vehicle to travel to ALMA, and prior to their trip they should send the license plate number and driver details to visit@alma.cl. Additional vehicles will enter the observatory in caravan behind the ALMA bus.
The OSF Tour
  1. During the tour, you will be taken to the ALMA Operations Support Facility (OSF) where ALMA personnel work and live.
  2. You will have the chance to see the control room, the laboratories and usually an antenna undergoing maintenance and the antenna transporter.
  3. For safety reasons, the Array Operation Site (AOS) on the Chajnantor plateau, at 5000 metres above sea level (where ALMA antennas are) is not open to visitors.

While at the ALMA OSF

  • Wear sunglasses, a hat, protective clothing and sunscreen over SPF35.
  • Drink plenty of bottled water or juice.
  • Move around slowly.
  • Do not leave litter.
  • Smoking is not allowed.
  • Illegal drugs and alcohol use are forbidden.
  • If you feel unwell: inform your guide immediately!
  • In an emergency: follow the guide and the Emergency Coordinator’s instructions.
  • Follow your guide’s instructions at all times throughout the tour.
  • Please find more information here: Health & Safety advice.
  • Be curious — ask lots of questions!
  • Take zillions of pictures!

Group Visits to the ALMA Operations Support Facility

  • In addition to the weekend visits for tourists and the general public, ALMA hosts guided visits of the ALMA Operations Support Facility for groups from schools, universities, institutes and related scientific organisations on Mondays, Wednesdays, Thursdays and Fridays.
  • All visits must be requested at least one month in advance by providing all of the information required on the form here. Once a group receives authorisation, the contact for the group will receive a confirmation email.
  • We can receive groups of up to 40 people (including students, professors and/or parents/guardians). The visiting group must have its own means of transport to the Observatory (OSF or the ALMA camp) located 35 kilometres from San Pedro de Atacama.
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