They believe such objects exist in a halolike swarm around our galaxy. Since the team found 20 machos in a relatively tiny slice of the galaxy, it figures these invisible objects can account for about half the mass of the galaxy, or about 325 billion times the weight of our sun, Alcock said. Alcock said Wednesday from an Australian conference where his team's research was being discussed. Alcock acknowledged it would be a major stretch to apply his research to a broader search for the 99 percent of the universe that also appears to be missing. Other astrophysicists said whatever Alcock found is important, but that even if true his theory would provide only half an answer to the astronomical puzzle.
Half is better than none.
Rubin added that the mystery of the missing mass is so complex that astronomers can't be sure just how significant Alcock's results are. Alcock used a long-known astronomical phenomenon called gravitation lensing in his research. Alcock's team used the effect to figure out what is making some stars suddenly shine as much as 50 times brighter. The team looked at stars from the far-away Large Magellanic Cloud and watched them brighten on occasion. One of those rare twinklings is going on now, Alcock said.