What is LOFAR?

ASTRON is now buidling a new telescope: LOFAR. LOFAR is short for Low Frequency Array and will become the largest radio telescope in the world that will perform observations in the lower frequencies. This new generation radio telescope will be able to research the origin of the first galaxies, black holes and gas clouds at the 'birth' of the Universe.  

LOFAR exists of thousands of small antennas, placed in stations in the central LOFAR area of 400 hectare between Exloo and Buinen in Drenthe, and on about eighteen smaller antenna fields (about two hectare) spread over the North of the Netherlands: Friesland, Groningen, Drenthe and Overijssel.

The antenna stations are connected through a very fast glass fiber network. This leads to the supercomputer of the Donald Smits Centre for Information Technology, that combines the dataof thousands of antennas. With this software a virtual dish is created with a diameter of about 100 kilometers. The model will be expanded with antenna stations in Germany, the UK, France and Sweden, which allows astronomers to observe even sharper detail. The largest distance between antennas will be about 1500 kilometers.

Looking back in time

The light of the Sun takes eight minutes to reach the Earth. Light and other signals of the nearest star take a few y ears to reach the Earth. Signals of even more distant objects and galaxies take millions and even billions of years before astronomers can observe them. So astronomers can look back in time. They want to observe objects that are so far away that the signals have traveled 13,7 billion years to reach Earth.

This requires a telescopes that is much bigger and much more sensitive than ASTRON's Westerbork Synthesis Radio Telescope. This is why ASTRON developed LOFAR. LOFAR exists of about 25,000 small antennas, of which about 7,000 are located in the central area in Drenthe.

The complete LOFAR project costs about one hundred million Euro. The Dutch government, Samenwerkingsverband Noord Nederland (SNN), the European Union and universities, research institutes and the businesses world contribute to the project.  

LOFAR exists of two antennas:  Low Band Antennas (LBA, see left), performing observations between 10 and 90 MHz, and High Band Antennes (HBA, see right), performing observations between 110 and 250 MHz.

New discoveries 

LOFAR will receive signals from the Universe that have never been examined. This opens up a complete new range of discoveries. LOFAR will be observing objects that have originated just after the Big Bang. LOFAR will also be able to give unique insights into phenomena closer to Earth: magnetic storms on the sun, solar winds and the way the climate influences the Earth. LOFAR also has other possibilities, it can contribute largely to research and development in other fields, such geophysics and agriculture.

All LOFAR stations are connected through very fast glass fibers to the supercomputer of the Donald Smits Centre for Information Technology of the University of Groningen. This is where the data, received by the antennas, are processed.

LOFAR in Europe

Several international stations are contructed or planned in Germany (5), Sweden (1) , the UK (1), France (1), Poland and Italy.

Observing with LOFAR

For practical and technical information on how to apply for LOFAR time and use the instrument please visit the Radio Observatory pages.

More LOFAR information

http://www.lofar.org/.