Milky Way tightens reins on speeding Large Magellanic Cloud

London, August 18 : A new analysis has suggested that the Milky Way would be able to hold on to the Large Magellanic Cloud (LMC), in spite of it speeding through space at lightening fast speed.

Last year, astronomers got a shock when it emerged that our galaxy's brightest companion, the Large Magellanic Cloud, appeared to be speeding through space so fast that we wouldn't be able to hold onto it.

But now, according to a report in New Scientist, two new measurements suggest the Milky Way will manage to keep its companion after all.

The first shows our galaxy to be spinning faster than we had thought. A star near the sun on a circular orbit round the galactic centre now appears to travel at 251 kilometres per second, compared with a previous figure of 220 km/s.

The centre of the galaxy now appears to be 27,400 light years from Earth, slightly further than the older figure of 26,100 light years.

Taken together, these findings imply that the Milky Way has about 50 per cent more mass than previously estimated, according to Genevieve Shattow and Abraham Loeb of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

This would make its gravity correspondingly stronger.

Because astronomers measure the LMC's speed relative to that of the sun, its estimated speed goes down 10 per cent, implying that it orbits the Milky Way every 6 billion years and reaches a maximum distance of 1.1 million light years.

According to Carlton Pryor of Rutgers University in New Jersey, the new work is probably correct.

"When I saw this result, it was a little bit of an 'aha' moment," he said. The Milky Way has torn a 300,000-light-year-long stream of gas out of the LMC. If it were approaching us for only the first time, there wouldn't have been enough time for the stream to have grown so large," he said.

ANI