Climbing the space ladder

Climbing the space ladder

The Hubble Space Telescope (NASA and ESA) decided to please us with a photograph of an ancient flickering collection of stars called NGC 1466. This is a globular cluster (a group of stars held by gravity) that slowly moves in space on the edge of the Large Magellanic Cloud (a neighbor of the Milky Ways).

Before us is a rather extreme sample of clusters. The mass of NGC 1466 is equal to 140,000 solar, and by age it reaches 13.1 billion years. That is, this cluster is almost as old as the Universe itself. This fossil cosmic relic from early space is 160,000 light-years distant from us. In this ancient time capsule reside 49 known RR Lyra variables, which are used to measure distances in space. These are great tools, as they are endowed with clearly defined brightness, and scientists know how much energy they release. When comparing this brightness with other stars, one can clearly calculate the distance in space. Such astronomical objects are called standard candles for the space distance ladder.

Comments (0)
Search