太阳西侧临边的条珥

太阳西侧临边的条珥

ByNASA中文

2022年6月24日 Filaprom on the Western Limb Image Credit & Copyright: Martin Wise Explanation: A solar filament is an enormous stream of incandescent plasma suspended above the active surface of the Sun by looping magnetic fields. Seen against the solar disk it looks dark only because it’s a little cooler, and so slightly dimmer, than the solar photosphere. Suspended above the solar limb the same structure looks bright when viewed against the blackness of space and is called a solar prominence. A filaprom would be both of course, a stream of magnetized plasma that crosses in front of the solar disk and extends beyond the Sun’s edge. In this hydrogen-alpha close-up of the Sun captured on June 22, active region AR3038 is near the center of…

螺旋星系NGC 6744

螺旋星系NGC 6744

ByNASA中文

2022年6月23日 Spiral Galaxy NGC 6744 Image Credit & Copyright: Basudeb Chakrabarti Explanation: Beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across, larger than our own Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo but appears as only a faint, extended object in small telescopes. We see the disk of the nearby island universe tilted towards our line of sight in this remarkably detailed galaxy portrait, a telescopic view that spans an area about the angular size of a full moon. In it, the giant galaxy’s elongated yellowish core is dominated by the light from old, cool stars. Beyond the core, grand spiral arms are filled with young blue star clusters and speckled with pinkish star forming regions. An…

超新星遗迹：面纱星云

超新星遗迹：面纱星云

ByNASA中文

2022年6月22日 Supernova Remnant: The Veil Nebula Image Credit & Copyright: Craig Stocks (Utah Desert Remote Observatories) Explanation: Ten thousand years ago, before the dawn of recorded human history, a new light would have suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was from a supernova, or exploding star, and record the expanding debris cloud as the Veil Nebula, a supernova remnant. Imaged with color filters featuring light emitted by sulfur (red), hydrogen (green), and oxygen (blue), this deep wide-angle view was processed to remove the stars and so better capture the impressive glowing filaments of the Veil. Also known as the Cygnus Loop, the Veil Nebula is roughly circular in shape and covers nearly 3…

台北上空的日行迹

台北上空的日行迹

ByNASA中文

2022年6月21日 Analemma over Taipei Image Credit & Copyright: Meiying Lee Explanation: Does the Sun return to the same spot on the sky every day? No. A better and more visual answer to that question is an analemma, a composite of images taken at the same time and from the same place over the course of a year. The featured analemma was compiled at 4:30 pm many afternoons from Taiwan during 2021, with the city skyline of Taipei in the foreground, including tall Taipei 101. The Sun’s location in December — at the December solstice — is shown on the far left, while its location at the June solstice is captured on the far right. Also shown are the positions of the Sun throughout the rest…

火星上的手指石

火星上的手指石

ByNASA中文

2022年6月20日 Rock Fingers on Mars Image Credit: NASA, JPL-Caltech, MSSS Explanation: There, just right of center, what is that? The surface of Mars keeps revealing new surprises with the recent discovery of finger-like rock spires. The small nearly-vertical rock outcrops were imaged last month by the robotic Curiosity rover on Mars. Although similar in size and shape to small snakes, the leading explanation for their origin is as conglomerations of small minerals left by water flowing through rock crevices. After these relatively dense minerals filled the crevices, they were left behind when the surrounding rock eroded away. Famous rock outcrops on Earth with a similar origin are called hoodoos. NASA’s Curiosity Rover continues to search for new signs of ancient water in Gale Crater on…

游戏：超级行星传奇

游戏：超级行星传奇

ByNASA中文

2022年6月19日 Game: Super Planet Crash Game Credit & License: Stefano Meschiari (U. Texas at Austin) & the SAVE/Point Team Explanation: Can you create a planetary system that lasts for 1000 years? Super Planet Crash, the featured game, allows you to try. To create up to ten planets, just click anywhere near the central star. Planet types can be selected on the left in order of increasing mass: Earth, Super-Earth, Ice giant, Giant planet, Brown dwarf, or Dwarf star. Each planet is gravitationally attracted not only to the central Sun-like star, but to other planets. Points are awarded, with bonus factors applied for increasingly crowded and habitable systems. The game ends after 1000 years or when a planet is gravitationally expelled. Many exoplanetary systems are being…

天津一与星云

天津一与星云

ByNASA中文

2022年6月18日 The Gamma Cygni Nebula Image Credit & Copyright: Min Xie, Chen Wu, Yizhou Zhang, and Benchu Tang Explanation: Supergiant star Gamma Cygni is at the center of the Northern Cross. Near the plane of our Milky Way galaxy, that famous asterism flies high in northern summer night skies in the constellation Cygnus the Swan. Known by the proper name Sadr, Gamma Cygni also lies just below center in this telescopic skyscape, with colors mapped from both broadband and narrowband image data. The field of view spans about 3 degrees (six Full Moons) on the sky and includes emission nebula IC 1318 and open star cluster NGC 6910. Filling the upper part of the frame and shaped like two glowing cosmic wings divided by a…

智利清晨的五星联珠

智利清晨的五星联珠

ByNASA中文

2022年6月17日 Good Morning Planets from Chile Image Credit & Copyright: Elke Schulz (Daniel Verschatse Observatory) Explanation: On June 15, innermost planet Mercury had wandered about as far from the Sun as it ever gets in planet Earth’s sky. Near the eastern horizon just before sunrise it stands over distant Andes mountain peaks in this predawn snapshot from the valley of Rio Hurtado in Chile. June’s other morning planets are arrayed above it, as all the naked-eye planets of the Solar System stretch in a line along the ecliptic in the single wide-field view. Tilted toward the north, the Solar System’s ecliptic plane arcs steeply through southern hemisphere skies. Northern hemisphere early morning risers will see the lineup of planets along the ecliptic at a shallower…

来自中国的超级莓月

来自中国的超级莓月

ByNASA中文

2022年6月16日 Strawberry Supermoon from China Image Credit & Copyright: Jeff Dai (TWAN) Explanation: There are four Full Supermoons in 2022. Using the definition of a supermoon as a Full Moon near perigee, that is within at least 90% of its closest approach to Earth in a given orbit, the year’s Full Supermoon dates are May 16, June 14, July 13, and August 12. Full Moons near perigee really are the brightest and largest in planet Earth’s sky. But size and brightness differences between Full Moons are relatively small and an actual comparison with other Full Moons is difficult to make by eye alone. Two exposures are blended in this supermoon and sky view from June 14. That Full Moon was also known to northern hemisphere…

室女星系团的核心

室女星系团的核心

ByNASA中文

2022年6月15日 In the Heart of the Virgo Cluster Image Credit & Copyright: Saulius Adomaitis Explanation: The Virgo Cluster of Galaxies is the closest cluster of galaxies to our Milky Way Galaxy. The Virgo Cluster is so close that it spans more than 5 degrees on the sky – about 10 times the angle made by a full Moon. With its heart lying about 70 million light years distant, the Virgo Cluster is the nearest cluster of galaxies, contains over 2,000 galaxies, and has a noticeable gravitational pull on the galaxies of the Local Group of Galaxies surrounding our Milky Way Galaxy. The cluster contains not only galaxies filled with stars but also gas so hot it glows in X-rays. Motions of galaxies in and around…