加法夏望远镜的螺旋星云

加法夏望远镜的螺旋星云

2023年5月7日 The Helix Nebula from CFHT Image Credit: CFHT, Coelum, MegaCam, J.-C. Cuillandre (CFHT) & G. A. Anselmi (Coelum) Explanation: Will our Sun look like this one day? The Helix Nebula is one of brightest and closest examples of a planetary nebula, a gas cloud created at the end of the life of a Sun-like star. The outer gasses of the star expelled into space appear from our vantage point as if we are looking down a helix. The remnant central stellar core, destined to become a white dwarf star, glows in light so energetic it causes the previously expelled gas to fluoresce. The Helix Nebula, given a technical designation of NGC 7293, lies about 700 light-years away towards the constellation of the Water Bearer…

M88

M88

2022年12月28日 Messier 88 Image Credit & Copyright: Adam Block, Mt. Lemmon SkyCenter, U. Arizona Explanation: Charles Messier described the 88th entry in his 18th century catalog of Nebulae and Star Clusters as a spiral nebula without stars. Of course the gorgeous M88 is now understood to be a galaxy full of stars, gas, and dust, not unlike our own Milky Way. In fact, M88 is one of the brightest galaxies in the Virgo Galaxy Cluster some 50 million light-years away. M88’s beautiful spiral arms are easy to trace in this sharp cosmic portait. The arms are lined with young blue star clusters, pink star-forming regions, and obscuring dust lanes extending from a yellowish core dominated by an older population of stars. Spiral galaxy M88 spans…

NGC 7293:螺旋星云

NGC 7293:螺旋星云

2022年12月7日 NGC 7293: The Helix Nebula Image Credit & Copyright: Tommaso Stella Explanation: A mere seven hundred light years from Earth, toward the constellation Aquarius, a sun-like star is dying. The dying star’s last few thousand years have produced the Helix Nebula (NGC 7293), a well studied and nearby example of a Planetary Nebula, typical of this final phase of stellar evolution. Combining narrow band image data from emission lines of hydrogen atoms in red and oxygen atoms in blue-green hues, it shows tantalizing details of the Helix, including its bright inner region about 3 light-years across. The white dot at the Helix’s center is this Planetary Nebula’s hot, central star. A simple looking nebula at first glance, the Helix is now understood to have…

NGC 7293: 螺旋星云

NGC 7293: 螺旋星云

2021年10月14日 NGC 7293: The Helix Nebula Image Credit & Copyright: Ignacio Diaz Bobillo Explanation: A mere seven hundred light years from Earth, toward the constellation Aquarius, a sun-like star is dying. Its last few thousand years have produced the Helix Nebula (NGC 7293), a well studied and nearby example of a Planetary Nebula, typical of this final phase of stellar evolution. A total of 90 hours of exposure time have gone in to creating this expansive view of the nebula. Combining narrow band image data from emission lines of hydrogen atoms in red and oxygen atoms in blue-green hues, it shows remarkable details of the Helix’s brighter inner region about 3 light-years across. The white dot at the Helix’s center is this Planetary Nebula’s hot,…

加法夏望远镜拍摄的螺旋星云

加法夏望远镜拍摄的螺旋星云

2020年11月24日 The Helix Nebula from CFHT Image Credit & Copyright: CFHT, Coelum, MegaCam, J.-C. Cuillandre (CFHT) & G. A. Anselmi (Coelum) Explanation: Will our Sun look like this one day? The Helix Nebula is one of brightest and closest examples of a planetary nebula, a gas cloud created at the end of the life of a Sun-like star. The outer gasses of the star expelled into space appear from our vantage point as if we are looking down a helix. The remnant central stellar core, destined to become a white dwarf star, glows in light so energetic it causes the previously expelled gas to fluoresce. The Helix Nebula, given a technical designation of NGC 7293, lies about 700 light-years away towards the constellation of the…

布蓝柯及哈勃望远镜拍摄的螺旋星云

布蓝柯及哈勃望远镜拍摄的螺旋星云

2020年8月23日 The Helix Nebula from Blanco and Hubble Image Credit: C. R. O’Dell, (Vanderbilt) et al. ESA, NOAO, NASA Explanation: How did a star create the Helix nebula? The shapes of planetary nebula like the Helix are important because they likely hold clues to how stars like the Sun end their lives. Observations by the orbiting Hubble Space Telescope and the 4-meter Blanco Telescope in Chile, however, have shown the Helix is not really a simple helix. Rather, it incorporates two nearly perpendicular disks as well as arcs, shocks, and even features not well understood. Even so, many strikingly geometric symmetries remain. How a single Sun-like star created such beautiful yet geometric complexity is a topic of research. The Helix Nebula is the nearest planetary…