天体三角

天体三角

2020 April 15 A Cosmic Triangle Image Credit & Copyright: Scott Aspinall Explanation: It was an astronomical triple play. Setting on the left, just after sunset near the end of last month, was our Moon — showing a bright crescent phase. Setting on the right was Venus, the brightest planet in the evening sky last month — and this month, too. With a small telescope, you could tell that Venus’ phase was half, meaning that only half of the planet, as visible from Earth, was exposed to direct sunlight and brightly lit. High above and much further in the distance was the Pleiades star cluster. Although the Moon and Venus move with respect to the background stars, the Pleiades do not — because they are…

四月的金星和昴宿星团

四月的金星和昴宿星团

2020 April 11 Venus and the Pleiades in April Image Credit & Copyright: Antonio Finazzi Explanation: Shared around world in early April skies Venus, our brilliant evening star, wandered across the face of the lovely Pleiades star cluster. This timelapse image follows the path of the inner planet during the beautiful conjunction showing its daily approach to the stars of the Seven Sisters. From a composite of tracked exposures made with a telephoto lens, the field of view is also appropriate for binocular equipped skygazers. While the star cluster and planet were easily seen with the naked-eye, the spiky appearance of our sister planet in the picture is the result of a diffraction pattern produced by the camera’s lens. All images were taken from a…

金星与昴宿星团

金星与昴宿星团

2020 April 4 Venus and the Sisters Image Credit & Copyright: Fred Espenak (Bifrost Astronomical Observatory) Explanation: After wandering about as far from the Sun on the sky as Venus can get, the brilliant evening star is crossing paths with the sister stars of the Pleiades cluster. Look west after sunset and you can share the ongoing conjunction with skygazers around the world. Taken on April 2, this celestial group photo captures the view from Portal, Arizona, USA. Even bright naked-eye Pleiades stars prove to be much fainter than Venus though. Apparent in deeper telescopic images, the cluster’s dusty surroundings and familiar bluish reflection nebulae aren’t quite visible, while brighter Venus itself is almost overwhelming in the single exposure. And while Venus and the Sisters…

交通忙碌的金牛座

交通忙碌的金牛座

2020 April 3 The Traffic in Taurus Image Credit & Copyright: Lionel Majzik Explanation: There’s a traffic jam in Taurus lately. On April 1, this celestial frame from slightly hazy skies over Tapiobicske, Hungary recorded an impressive pile up toward the zodiacal constellation of the Bull and the Solar System’s ecliptic plane. Streaking right to left the International Space Station speeds across the bottom of the telescopic field of view. Wandering about as far from the Sun in planet Earth’s skies as it can get, inner planet Venus is bright and approaching much slower, overexposed at the right. Bystanding at the upper left are the sister stars of the Pleiades. No one has been injured in the close encounter though, because it really isn’t very…

四月天空的金星和昴宿星团

四月天空的金星和昴宿星团

2020 April 2 Venus and the Pleiades in April Digital Illustration Credit & Copyright: Fred Espenak (Bifrost Astronomical Observatory) Explanation: Venus is currently the brilliant evening star. Shared around world, in tonight’s sky Venus will begin to wander across the face of the lovely Pleiades star cluster. This digital sky map illustrates the path of the inner planet as the beautiful conjunction evolves, showing its position on the sky over the next few days. The field of view shown is appropriate for binocular equipped skygazers but the star cluster and planet are easily seen with the naked-eye. As viewed from our fair planet, Venus passed in front of the stars of the Seven Sisters 8 years ago, and will again 8 years hence. In fact,…

从昴宿星团到毕宿星团

从昴宿星团到毕宿星团

2019 December 6 Pleiades to Hyades Image Credit & Copyright: Amir H. Abolfath (TWAN) Explanation: This cosmic vista stretches almost 20 degrees from top to bottom, across the dusty constellation Taurus. It begins at the Pleiades and ends at the Hyades, two star clusters recognized since antiquity in Earth’s night sky. At top, the compact Pleiades star cluster is about 400 light-years away. The lovely grouping of young cluster stars shine through dusty clouds that scatter blue starlight. At bottom, the V-shaped Hyades cluster looks more spread out in comparison and lies much closer, 150 light-years away. The Hyades cluster stars seem anchored by bright Aldebaran, a red giant star with a yellowish appearance. But Aldebaran actually lies only 65 light-years distant and just by…

M45:阿特拉斯与普勒俄涅的女儿们

M45:阿特拉斯与普勒俄涅的女儿们

2019 November 7 Messier 45: The Daughters of Atlas and Pleione Image Credit & Copyright: Adam Block, Steward Observatory, University of Arizona 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 and cosmic dust cloud are not related 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…

M45: 昴宿星团

M45: 昴宿星团

2019 September 1 M45: The Pleiades Star Cluster Image Credit & Copyright: Marco Lorenzi (Glittering Lights) Explanation: Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as dusty as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen without binoculars from even the depths of a light-polluted city. With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident. The featured exposure took over 12 hours and covers a sky area several times the size of the full moon. Also known as the Seven Sisters and M45, the Pleiades lies about 400 light years away toward the…