New images from the Gemini Observatory in Hawaii show a pair of beautiful nebulae that were created by two very different types of stars that might be at similar points in their evolutionary timelines.

One is NGC 6145-5 (top image), a nebula that lies about 4,200 light-years away in the constellation Norma. At the center of the nebula is HD 148937, an aging star that is 40 times more massive than the Sun and about three to four million years of age. HD 148937 is a rare type of very massive spectra-type "O" star that is heating up its surrounding clouds of gas with ultraviolet light. The star is surrounded by material it ejected in an explosive event earlier in its life and is losing mass in a steady "stellar wind." HD 148937 is aging fast and scientists think it will likely end its life in an a violent supernova explosion.

The other nebula, NGC 5189 (bottom image), is a star originally more similar to our Sun that lost its outer envelope following a "red giant" phase. It also continues to blow its mass away in stellar winds. NGC 5189 lies about 1,800 light-years away in the southern hemisphere constellation Musca. At the core of NGC 5189 is the hot, hydrogen-deficient star HD 117622 that is blowing off its thin atmosphere into interstellar space at a speed of about 1,700 miles (2,700 kilometers) per second.

-- Ker Than

Credit: Travis Rector/University of Alaska Anchorage