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"Astronomy and Astrophysics for the 1980's," is an approved 

 program which deserves special mention. It calls for ten 25 

 meter telescopes spanning the continent from the U.S. -Canadian 

 border to Puerto Rico and from Hawaii to the Atlantic coast. 

 The entire array will have the resolving power of a single 

 telescope 8000 kilometers in diameter. With a resolution of 

 about 3 X lO-** arc seconds, it will probe the hearts of 

 quasars, the most incredibly powerful energy machines in the 

 universe. The VLBA is expected to cost about 70 million dollars 

 with an annual operating budget of about 5 million dollars. 



In past developments of long base line radio interferometry, 

 international cooperation has played an important role. Links 

 have been set up between U.S. telescopes and instruments in the 

 U.S.S.R., Scandinavia, West Germany, and Australia. While the 

 VLBA is planned to operate as a U.S. instrument, foreign 

 astronomers will be welcome users. More important in the 

 context of international cooperation is the prospect of similar 

 instruments being built in other countries. Canadians are 

 planning an array of eight 32 meter telescopes across the 

 southern part of the country and possibly a ninth at Yellow 

 Knife in the northwest territories. The digitized data will be 

 recorded in the same format as that of the VLBA which will 

 permit special coordinated observations combining the power of 

 both arrays. 



