ALMA is located in the Atacama Desert of northern Chile at an altitude of 5000 meters.

ALMA was built in the world’s best observation site for receiving radio waves from the universe. The selected site satisfies all the necessary conditions for radio observations such as dry air with a low rate of water vapor absorption of radio waves and a wide flat space that allows an extended configuration of multiple antennas. With such ideal conditions, the 5000-m high plateau in Chile was chosen among other candidate sites including Hawaii and China.

In the ALMA site at an elevation of 5000 meters, the air is very thin and the amount of oxygen is only half of that at sea level. Annual rainfall is very low, which makes the air extremely dry. ALMA staff working at the high site have to protect themselves from the exposure to strong sunshine which could cause sunburn.

Since Chile and Japan are located on the other side of the earth, it takes 30 hours or more (including connection time) only to fly to Santiago, the capital of Chile, and it takes 1.5 days or more in total to go to the ALMA Operations Support Facility (OSF).

While the public visit to the ALMA Array Operations Site (AOS) at 5000 meters where the antennas are located is not allowed for safety reasons, the Operations Support Facility (OSF) at 2900 meters from which the antennas are remotely controlled is open to the public on weekend. To obtain an entry pass, advance registration is required. For detailed information, see Visit.

ALMA is a radio telescope to capture radio waves coming from the universe. There are various types of telescopes to observe the universe at different wavelengths of the electromagnetic spectrum. For example, the optical telescopes such as the Subaru Telescope and the Hubble Space Telescope observe the visible light that can be captured by human eyes. There are also other types of telescopes to observe in regions of the infrared, ultraviolet, X-rays, and gamma rays, etc. ALMA captures millimeter/submillimeter waves that are suitable for observing star-forming materials such as dust and gas.

ALMA is openly used by researchers around the world. ALMA observation proposals are solicited worldwide and the selection committee selects observation programs to be given priority.

Observation time will be allocated to North America (approx.30%), the European Southern Observatory (ESO) member states (approx. 30%), East Asia (approx. 20%), and to the host country, Chile (approx. 10%) and the rest (up to 5%) will be allocated to researchers of other regions (based on open sky policy). The observing time are divided among North America, ESO member states, and East Asia in proportion to their shares of contributions for ALMA construction and operations.
In accordance with this policy, ALMA is openly available to every researcher around the world regardless of the regions or institutes to which they belong.
The first call for proposals was issued in March 2011, and the sixth round of the scientific observation is scheduled for 2017.

ALMA observations are performed not by a researcher but by a specialized operator. A researcher who submitted an observation proposal only has to wait for his/her observation data to arrive after his/her proposal was adopted and implemented. This means, even staying in Japan, researchers can conduct leading-edge researches using ALMA.

It’s not easy to obtain observation time for an observation proposal in a fierce competition among a large of number of researchers around the world. Obtained observation data is firstly sent to a researcher who submitted the proposal, and after a proprietary period of one year, the data will be stored in the ALMA archive that is accessible from all over the world. In other words, past observation data will become available to everyone who wish to conduct research with it, and the same observation data can be utilized for multiple research themes with different approaches.
Also, ALMA has thee ALMA Regional Centers to provide support for researchers. The East Asian ALMA Regional Center (EA ARC), located at the National Astronomical Observatory of Japan (NAOJ), provides support for researchers in Japan and other East Asian regions. Through the ALMA Regional Centers, it is expected that ALMA will be used not only by astronomers but also by scientists of other fields.

ALMA was constructed with funds, technologies, and human resources provided by various countries of the world. Before ALMA, telescopes were mostly constructed and operated by one country or by one research institute like a university. However, researchers aspired to realize an unprecedented high-performance telescope and launched the international ALMA project.
ALMA is a pioneer telescope that created a new global trend to make a giant telescope in international partnership. ALMA is a “telescope for human race” that has been realized by global collaboration.

Japan on behalf of East Asia developed the Morita Array that consists of 16 parabolic antennas, receivers and correlators: more specifically, four 12-m antennas, twelve 7-m antennas (16 antennas in total), three types of receivers, and a supercomputer (correlators) capable of simultaneously processing radio waves collected by 16 antennas. Various Japanese state-of-the-art technologies were integrated into the development of these components.
Currently, about 20 researchers and engineers from Japan are stationed in Chile for the operations of ALMA. In Japan, scientists are working on future development programs for further upgrades of ALMA.

ALMA is a radio telescope or radio interferometer that combines 66 parabolic antennas working as a single virtual giant telescope. The most compact antenna configurations spread over 200 meters while the largest configuration reaches 16 km in diameter, which is equivalent to the diameter of the Yamanote Line (a railway loop line that circles central Tokyo) with a resolution comparable to a radio telescope with an aperture of 16 km.

ALMA boasts the world’s best observing capability that overwhelmingly surpasses other existing millimeter/submillimeter telescopes. ALMA can produce a high-resolution image of the universe by receiving weak radio signals with a sensitivity 100 times higher and a resolution (corresponding to a visual acuity of the human eye) several tens of times higher than other existing telescopes.

The total amount of the construction costs is about 150 billion yen or 1.5 billion dollars. Japanese monetary contribution is about 25 billion yen or 250 million dollars and the total Japanese share of contributions including equipment development and personnel contributions accounts for 25% of the total. In addition to this, Japan makes a contribution of 3 billion yen or 30 million dollars (25%) as annual operations costs.

ALMA aims to explore the three great mysteries of the universe:
1. To reveal the galaxy formation and trace the evolution history of the universe over 13.8 billion years;
2. To capture clear image of planetary forming regions and uncover the planetary formation process; and
3. To make detailed analyses of materials in the universe and investigate the link to the origin of life.
Also, ALMA will be used for various researches in other fields of study, which may deliver surprising results that we have never imagined.

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The contact point to ALMA in Japan is the NAOJ ALMA Project.
We can send researchers and engineers as speakers or lend miniature models, explanatory posters/panels and movies, etc. Please feel free to contact us from our inquiry form.
If you want to visit the ALMA site in Chile for news coverage or other TV/radio/magazine programs, you may send a request to the Joint ALMA Observatory.

Please contact us from our inquiry form.