沃尔夫-拉叶星WR 124

沃尔夫-拉叶星WR 124

2023年3月18日 Wolf-Rayet 124 Image Credit: NASA, ESA, CSA, STScI, Webb ERO Production Team Explanation: Driven by powerful stellar winds, expanding shrouds of gas and dust frame hot, luminous star Wolf-Rayet 124 in this sharp infrared view. The eye-catching 6-spike star pattern is characteristic of stellar images made with the 18 hexagonal mirrors of the James Webb Space Telescope. About 15,000 light-years distant toward the pointed northern constellation Sagitta, WR 124 has over 30 times the mass of the Sun. Produced in a brief and rarely spotted phase of massive star evolution in the Milky Way, this star’s turbulent nebula is nearly 6 light-years across. It heralds WR 124’s impending stellar death in a supernova explosion. Formed in the expanding nebula, dusty interstellar debris that survives…

巴纳德68: 黝黑的分子云

巴纳德68: 黝黑的分子云

2023年1月29日 Barnard 68: Dark Molecular Cloud Image Credit: FORS Team, 8.2-meter VLT Antu, ESO Explanation: Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark molecular cloud. Here, a high concentration of dust and molecular gas absorb practically all the visible light emitted from background stars. The eerily dark surroundings help make the interiors of molecular clouds some of the coldest and most isolated places in the universe. One of the most notable of these dark absorption nebulae is a cloud toward the constellation Ophiuchus known as Barnard 68, pictured here. That no stars are visible in the center indicates that Barnard 68 is relatively nearby, with measurements placing it about…

M45: 阿特拉斯和普勒俄涅的女儿们

M45: 阿特拉斯和普勒俄涅的女儿们

2023年1月5日 Messier 45: The Daughters of Atlas and Pleione Image Credit & Copyright: Stefan Thrun Explanation: Hurtling through a cosmic dust cloud a mere 400 light-years away, the lovely Pleiades or Seven Sisters open star cluster is well-known for its striking blue reflection nebulae. It lies in the night sky toward the constellation Taurus and the Orion Arm of our Milky Way galaxy. The sister stars are not related to the dusty cloud though. They just happen to be passing through the same region of space. Known since antiquity as a compact grouping of stars, Galileo first sketched the star cluster viewed through his telescope with stars too faint to be seen by eye. Charles Messier recorded the position of the cluster as the 45th…

蝌蚪星云的气体和尘埃

蝌蚪星云的气体和尘埃

2022年12月19日 The Tadpole Nebula in Gas and Dust Image Credit & Copyright: Craig Stocks (Utah Desert Remote Observatories) Explanation: What’s causing the commotion in the Tadpole Nebula? Star formation. Dusty emission in the Tadpole Nebula, IC 410, lies about 12,000 light-years away in the northern constellation of the Charioteer (Auriga). The cloud of glowing gas is over 100 light-years across, sculpted by stellar winds and radiation from embedded open star cluster NGC 1893. Formed in the interstellar cloud a mere 4 million years ago, bright newly formed cluster stars are seen all around the star-forming nebula. Notable on the lower-right of the featured image are two relatively dense streamers of material trailing away from the nebula’s central regions. Potentially sites of ongoing star formation in…

狼窟星云

狼窟星云

2022年11月15日 Wolf’s Cave Nebula Image Credit & Copyright: Gianni Lacroce Explanation: The mysterious blue reflection nebula found in catalogs as VdB 152 or Ced 201 really is very faint. It lies at the tip of the long dark nebula Barnard 175 in a dusty complex that has also been called Wolf’s Cave. At the center of this deep telescopic view, the cosmic apparitions are nearly 1,400 light-years away along the northern Milky Way in the royal constellation Cepheus. Interstellar dust in the region blocks light from background stars and scatters light from the embedded bright star, giving the end nebula its characteristic blue color. Though stars do form in molecular clouds, this star seems to have only accidentally wandered into the area, as its measured…

洞察号的最后自拍

洞察号的最后自拍

2022年11月4日 InSight’s Final Selfie Image Credit: NASA, JPL-Caltech, Mars InSight Explanation: The Mars InSight lander returned its first image from the Red Planet’s flat, equatorial Elysium Planitia after a successful touchdown on November 26, 2018. The history making mission to explore the martian Interior using Seismic investigations, geodesy, and heat transport has been operating for over 1,400 martian days or sols. In that time the InSight mission has detected more than 1,300 marsquakes and recorded data from Mars-shaking meteoroid impacts, observing how the seismic waves travel to provide a glimpse inside Mars. Analyzing the archive of data collected is expected to yield discoveries for decades. But InSight’s final operational sol is likely not far off. The reason is evident in this selfie recorded earlier this…

伽玛射线爆发周围的X射线环

伽玛射线爆发周围的X射线环

2022年10月17日 X-Ray Rings Around a Gamma Ray Burst Image Credit: NASA Swift Obs.; Data: B. Cenko (NASA’s GSFC), A. Beardmore (U. Leicester) et al.; Processing: J. Miller (U. Michigan) Explanation: Why would x-ray rings appear around a gamma-ray burst? The surprising answer has little to do with the explosion itself but rather with light reflected off areas of dust-laden gas in our own Milky Way Galaxy. GRB 221009A was a tremendous explosion — a very bright gamma-ray burst (GRB) that occurred far across the universe with radiation just arriving in our Solar System last week. Since GRBs can also emit copious amounts of x-rays, a bright flash of x-rays arrived nearly simultaneously with the gamma-radiation. In this case, the X-rays also bounced off regions high…

哈勃:红外波段的马头星云

哈勃:红外波段的马头星云

2022年9月21日 The Horsehead Nebula in Infrared from Hubble Image Credit: NASA, ESA, Hubble; Processing: Alexandra Nachman Explanation: While drifting through the cosmos, a magnificent interstellar dust cloud became sculpted by stellar winds and radiation to assume a recognizable shape. Fittingly named the Horsehead Nebula, it is embedded in the vast and complex Orion Nebula (M42). A potentially rewarding but difficult object to view personally with a small telescope, the featured gorgeously detailed image was taken in infrared light by the orbiting Hubble Space Telescope. The dark molecular cloud, roughly 1,500 light years distant, is cataloged as Barnard 33 and is seen above primarily because it is backlit by the nearby massive star Sigma Orionis. The Horsehead Nebula will slowly shift its apparent shape over the…

韦伯太空望远镜的船底座峭壁

韦伯太空望远镜的船底座峭壁

2022年9月5日 Carina Cliffs from the Webb Space Telescope Image Credit: NASA, ESA, CSA, STScI Explanation: Stars created these cliffs. Specifically, the destructive winds and energetic light from the stars in the open cluster NGC 3324 eroded away part of a mountain of dark interstellar dust in the northern part of the Carina Nebula. Several of these stars are visible toward the top of this highly detailed image taken recently by the James Webb Space Telescope, the largest astronomical telescope ever launched. Webb’s large mirror and ability to see dust-piercing infrared light has enabled it to capture fascinating details in the dust, hundreds of previously hidden stars, and even some galaxies far in the distance. The featured jagged cliffs occur in part of Carina known as…

小精灵星云的尘埃云

小精灵星云的尘埃云

2022年8月10日 Dust Clouds of the Pacman Nebula Image Credit & Copyright: Douglas J. Struble (Future World Media) Explanation: Stars can create huge and intricate dust sculptures from the dense and dark molecular clouds from which they are born. The tools the stars use to carve their detailed works are high energy light and fast stellar winds. The heat they generate evaporates the dark molecular dust as well as causing ambient hydrogen gas to disperse and glow red. Pictured here, a new open cluster of stars designated IC 1590 is nearing completion around the intricate interstellar dust structures in the emission nebula NGC 281, dubbed the Pac-man Nebula because of its overall shape. The dust cloud on the upper left is classified as a Bok Globule…