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2019 February 21 Reflections on vdB 9 Image Credit & Copyright: Guenter Kerschhuber Explanation: Centered in a well-composed celestial still life, pretty, blue vdB 9 is the 9th object in Sidney van den Bergh’s 1966 catalog of reflection nebulae. It shares this telescopic field of view, about twice the size of a full moon on the sky, with stars and dark, obscuring dust clouds in the northerly constellation Cassiopeia. Cosmic dust is preferentially reflecting blue starlight from embedded, hot star SU Cassiopeiae, giving vdB 9 the characteristic bluish tint associated with a classical reflection nebula. SU Cas is a Cepheid variable star, though even at its brightest it is just too faint to be seen with the unaided eye. Still Cepheids play an important role…

2019 February 20 Doomed Star Eta Carinae Image Credit: NASA, ESA, Hubble; Processing & License: Judy Schmidt Explanation: Eta Carinae may be about to explode. But no one knows when – it may be next year, it may be one million years from now. Eta Carinae’s mass – about 100 times greater than our Sun – makes it an excellent candidate for a full blown supernova. Historical records do show that about 170 years ago Eta Carinae underwent an unusual outburst that made it one of the brightest stars in the southern sky. Eta Carinae, in the Keyhole Nebula, is the only star currently thought to emit natural LASER light. This featured image brings out details in the unusual nebula that surrounds this rogue star….

2019 February 19 Comet Iwamoto Before Spiral Galaxy NGC 2903 Video Credit & Copyright: Norbert Span Explanation: It isn’t every night that a comet passes a galaxy. Last Thursday, though, binocular comet C/2018 Y1 (Iwamoto) moved nearly in front of a spiral galaxy of approximately the same brightness: NGC 2903. Comet Iwamoto was discovered late last year and orbits the Sun in a long ellipse. It last visited the inner Solar System during the Middle Ages, around the year 648. The comet reached its closest point to the Sun — between Earth and Mars — on February 6, and its closest point to Earth a few days ago, on February 13. The featured time-lapse video condenses almost three hours into about ten seconds, and was…

2019 February 18 Dragon Aurora over Iceland Image Credit & Copyright: Jingyi Zhang & Wang Zheng Explanation: Have you ever seen a dragon in the sky? Although real flying dragons don’t exist, a huge dragon-shaped aurora developed in the sky over Iceland earlier this month. The aurora was caused by a hole in the Sun’s corona that expelled charged particles into a solar wind that followed a changing interplanetary magnetic field to Earth’s magnetosphere. As some of those particles then struck Earth’s atmosphere, they excited atoms which subsequently emitted light: aurora. This iconic display was so enthralling that the photographer’s mother ran out to see it and was captured in the foreground. No sunspots have appeared on the Sun so far in February, making the…

2019 February 17 Shadow of a Martian Robot Image Credit: Mars Exploration Rover Mission, JPL, NASA Explanation: What if you saw your shadow on Mars and it wasn’t human? Then you might be the Opportunity rover currently exploring Mars. Opportunity explored the red planet from 2004 to 2018, finding evidence of ancient water, and sending breathtaking images across the inner Solar System. Pictured here in 2004, Opportunity looks opposite the Sun into Endurance Crater and sees its own shadow. Two wheels are visible on the lower left and right, while the floor and walls of the unusual crater are visible in the background. Caught in a dust storm in 2018, last week NASA stopped try contact Opportunity and declare the ground-breaking mission, originally planned for…

2019 February 16 NGC 2359: Thor’s Helmet Image Credit & Copyright: Ignacio Diaz Bobillo Explanation: NGC 2359 is a helmet-shaped cosmic cloud with wing-like appendages popularly called Thor’s Helmet. Heroically sized even for a Norse god, Thor’s Helmet is about 30 light-years across. In fact, the helmet is more like an interstellar bubble, blown as a fast wind from the bright, massive star near the bubble’s center inflates a region within the surrounding molecular cloud. Known as a Wolf-Rayet star, the central star is an extremely hot giant thought to be in a brief, pre-supernova stage of evolution. NGC 2359 is located about 15,000 light-years away in the constellation Canis Major. The remarkably detailed image is a mixed cocktail of data from broadband and narrowband…

2019 February 15 Opportunity at Perseverance Valley Image Credit: NASA, JPL-Caltech, Kenneth Kremer, Marco Di Lorenzo Explanation: Opportunity had already reached Perseverance Valley by June of 2018. Its view is reconstructed in a colorized mosaic of images taken by the Mars Exploration Rover’s Navcam. In fact, Perseverance Valley is an appropriate name for the destination. Designed for a 90 day mission, Opportunity had traveled across Mars for over 5,000 sols (martian solar days) following a January 2004 landing in Eagle crater. Covering a total distance of over 45 kilometers (28 miles), its intrepid journey of exploration across the Martian landscape has come to a close here. On June 10, 2018, the last transmission from the solar-powered rover was received as a dust storm engulfed the…

2019 February 14 Solar System Family Portait Image Credit: Voyager Project, NASA Explanation: On Valentine’s Day in 1990, cruising four billion miles from the Sun, the Voyager 1 spacecraft looked back one last time to make this first ever Solar System family portrait. The complete portrait is a 60 frame mosaic made from a vantage point 32 degrees above the ecliptic plane. In it, Voyager’s wide angle camera frames sweep through the inner Solar System at the left, linking up with gas giant Neptune, the Solar System’s outermost planet, at the far right. Positions for Venus, Earth, Jupiter, Saturn, Uranus, and Neptune are indicated by letters, while the Sun is the bright spot near the center of the circle of frames. The inset frames for…

2019 February 13 The Helix Nebula in Hydrogen and Oxygen Image Credit & Copyright: Andrew Campbell Explanation: Is the Helix Nebula looking at you? No, not in any biological sense, but it does look quite like an eye. The Helix Nebula is so named because it also appears that you are looking down the axis of a helix. In actuality, it is now understood to have a surprisingly complex geometry, including radial filaments and extended outer loops. The Helix Nebula (aka NGC 7293) 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 remnant central stellar core, destined to become a white dwarf star, glows in light so energetic…

2019 February 12 Plane Crossing a Crescent Moon Image Credit & Copyright: Olivier Staiger (Binounistan.com) Explanation: No, this is not a good way to get to the Moon. What is pictured is a chance superposition of an airplane and the Moon. The contrail would normally appear white, but the large volume of air toward the setting Sun preferentially knocks away blue light, giving the reflected trail a bright red hue. Far in the distance, well behind the plane, is a crescent Moon, also slightly reddened. Captured a month ago above Valais, Switzerland, the featured image was taken so soon after sunset that planes in the sky were still in sunlight, as were their contrails. Within minutes, unfortunately, the impromptu sky show ended. The plane crossed…