Milky Way as Large as Andromeda

2009/02/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Astronomia

A group of astronomers at the Harvard-Smithsonian Center in California calculates the size of the milky way from a network of radio telescopes: Very long base array. There are ten telescopes spread in the United States that, when used together, get very precise signals. The result of the measurement is that the Milky Way is 15% higher than expected, the approximate size of the Andromeda galaxy. To date, the size of the Milky Way was considered to be 100,000 light years.

To find out, astronomers have measured how far some of the star formation focuses are. The parallax method has been used, that is, the movement of these zones has been studied with respect to farther stars, seen from two points opposite the Earth orbit. With this data, through triangulation, you can know the distance to which the zones are located and from there the size of the galaxy is deduced.

In addition to the size, astronomers have measured how fast the entire galaxy is rotating with its center. This data is also higher than expected. In the end, with more precise measurements they have seen that the galaxy is larger than expected and has a faster rotation than expected.