Podcast 1.1

Sky watch Podcast

6/30/11

The Hubble Telescope has found an almost “fountain of youth” for stars in a classification of stars known as The Blue Stragglers or “born again stars”. They are the hottest and bluest, but burn out first leaving behind yellow stars like our sun and other dwarf stars. In addition, when compared to other stars around them they appear to be lagging behind in the aging process. Never have Blue Stragglers been detected in our own Milky Way galaxy… until now! The Hubble Telescope has located forty-two of these “oddball” stars; however, there is still no concrete explanation on how these aging stars change into youthful looking blue hot stars. There is one idea regarding this transformation. A pair of closely orbiting stars make one, massive star, when this happens their hydrogen is stirred up. This makes the newly merged stars hotter and bluer, resulting in Blue Stragglers.

The most important star in the universe has no name and is not even visible to the naked eye. What makes it special is that in 1923 Edwin Hubble discovered it was in a special class of pulsating star known as Cepheid variable stars. The rate at which they pulsate is a direct indication of their true brightness, which can then be measured to record actual distance. The variable star that Hubble analyzed (in Andromeda) was located outside the Milky Way; this proved that there are other galaxies outside our own. This expanded our knowledge of the known universe as Edwin Hubble proved that stars could exist outside our galaxy. Nearly a century later we can use the Hubble Space Telescope to look onto these distance galaxies and verify his results.