BLACK HOLES ARE THE MOST FUEL-EFFICIENT ENGINES IN THE UNIVERSE, THE US SPACE AGENCY NASA SAID MONDAY, ACCORDING TO DPA. NASA SCIENTISTS SAID THE NEW FINDINGS USING THE AGENCY'S CHANDRA X-RAY OBSERVATORY GAVE INSIGHT ON HOW NINE BLACK HOLES GENERATED THEIR HUGE ENERGY IN SPACE. IF A CAR WERE AS FUEL-EFFICIENT AS THESE BLACK HOLES, IT WOULD TRAVEL MORE THAN 1 BILLION MILES (1.6 BILLION KILOMETRES) ON ONE GALLON (3.8 LITRES) OF PETROL, SAID SAID CO-AUTHOR CHRISTOPHER REYNOLDS OF THE UNIVERSITY OF MARYLAND. BLACK HOLES - FORMER STARS SO MASSIVE THAT EVEN LIGHT CAN'T ESCAPE THEM - ALSO ARE 20 TIMES MORE EFFICIENT THAN NUCLEAR REACTORS, THE STUDY FOUND. THE SCIENTISTS SAID THEY CALCULATED THE SIZE OF THE GALAXIES' INNER REGIONS TO ESTIMATE HOW MUCH "FUEL" - GAS IN SPACE THAT IS DRAWN INTO THE BLACK HOLES - IS AVAILABLE. THEN, THE OBSERVATORY'S IMAGES WERE USED TO ESTIMATE HOW MUCH POWER WAS DEVELOPED BY THE RESULTING JETS OF HIGH-ENERGY PARTICLES TO CREATE HUGE BUBBLES, OR CAVITIES, IN THE GALAXIES' HOT GAS.
