CRI听力:ALMA and World Observatories Join Hands to Create Virtual Earth-sized Telescope

The Atacama Large Millimeter/submillimeter Array, or ALMA, is considered to be one of the largest astronomical observatories in the world.

It is joining up with institutes across Europe and North America to develop technology known as very long baseline interferometry, or VLBI.

The technology works by combining data gathered by two or more telescopes, creating a virtual telescope with a collection dish equal in size to the geographical distance between them.

Three VLBI tests have been conducted in conjunction with other international telescopes, a key step towards the observatory's integration in the Event Horizon Telescope project.

Head of ALMA operations at ALMA observatory, Lars-Ake Nyman, explains how their multi-national operation can provide a network of telescopes big enough to create a virtual earth-sized telescope.

"In various countries in the world there exist millimeter telescopes that can take millimeter radiation coming from objects in the universe. So there are telescopes in Europe like in Finland and in Sweden and Germany in France and in Spain, also in the United States, Hawaii, and Antarctica. And, there is the possibility to join all these telescopes, in what's called the VLBI (very long baseline interferometry) network to do these types of observations."

The project, which involves a global network of telescopes, serves scientists studying the supermassive black hole believed to be located in the centre of the Milky Way galaxy.

For ALMA to take part in the VLBI project, it had to upgrade its equipment in order for each of its telescopes to function in unison as a single radio dish 85 meters in diameter.

In this way, it could be integrated into the global network, working in turn as a single telescope.
Nyman says this is exciting news for astronomers.

"So I mean it's fantastic that all these countries are working together and they can form the status quo because with this telescope your form a telescope the size of the earth more-or-less when it comes to resolution and images. You can study very distant objects in much detail, and also closer objects, like the centre of our Milky Way, the Black Hole, can almost be resolved with these types of observations."

The first test was carried out in January this year, when one of the ALMA telescopes was linked to the Atacama Pathfinder Experiment telescope two kilometers away.

During a further test in August, ALMA linked up with six antennas of the U.S. National Radio Astronomy Observatory, to create a telescope capable of detecting a quasar located at a distance of 7.8 billion light years, or more than half the distance to the observable "edge" of the universe.

For CRI, I'm Luo Bin.