This image shows knots of cold, dense interstellar gas where new stars are forming. These Free-floating Evaporating Gaseous Globules (frEGGs) were first seen in Hubble’s famous 1995 image of the Eagle Nebula. Because these lumps of gas are dark, they are rarely seen by telescopes. They can be observed when the newly forming stars ignite, their intense ultraviolet radiation eroding the surrounding gas away and letting the denser, more resistant frEGGs remain. These frEGGs are located in the Northern Coalsack Nebula in the direction of Cygnus, the Swan.
这张图片显示了新恒星正在形成的寒冷、致密的星际气体结。这些自由漂浮的蒸发气态球体 (frEGG) 首次出现在哈勃1995年著名的鹰状星云图像中。这些气体块太暗，以致于望远镜很少能看到它们。当新形成的恒星点燃时，可以观察到它们，它们强烈的紫外线辐射侵蚀了周围的气体，让密度更大、阻力更大的frEGG保留下来。这些frEGG位于天鹅座方向的北方煤袋星云。
This Hubble image also features two giant stars. The left star is a rare, giant O-type star, very bright, blue-white stars known to be the hottest in the universe. These massive stars are 10,000 to a million times the brightness of the Sun and burn themselves out quickly, in a few million years. The right star is an even more massive supergiant B-type star. Supergiant stars also burn through their fuel quickly, anywhere between a few hundred thousand years to tens of millions of years, and die in titanic supernova explosions.
Image Credit: NASA, ESA, and R. Sahai (Jet Propulsion Laboratory); Processing: Gladys Kober (NASA/Catholic University of America)
影像来源：NASA, ESA, and R. Sahai (Jet Propulsion Laboratory); Processing: Gladys Kober (NASA/Catholic University of America)