A Cosmic EGG

This image, taken with the Hubble Space Telescope, depicts a special class of star-forming nursery known as Free-floating Evaporating Gaseous Globulesor frEGGs. Hot, young, massive stars are true powerhouses of the cosmos. Their double-whammy of ultraviolet light and a fierce radiation wind of charged particles – a kind of solar wind, but far more ferocious – is easily able to transform the nebula around them, which gave birth to these mighty stars. The gas within the nebula is ionised, and even blown completely away, creating a large, transparent bubble of hot plasma around the young star. However, such bubbles are not always completely empty. On occasion there may still reside a knot of dark gas and dust, too dense to be obliterated by the star’s violent emissions.

The frEGG pictured here is catalogued as J025157.5+600606 and embedded deep within the Soul Nebula, 7,500 light years away in the constellation of Cassiopeia. It is still in the process of forming low-mass stars within it, shielding them from the radiation of their more massive stellar brothers.

Image: Hubble and NASA/R. Sahai.