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Keyword: cometlemmon

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  • Astronomy Picture of the Day -- Tails of Comet Lemmon

    05/06/2013 4:04:21 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | May 06, 2013 | (see photo credit)
    Explanation: What caused the interestingly intricate tails that Comet Lemmon displayed earlier this year? First of all, just about every comet that nears the Sun displays two tails: a dust tail and an ion tail. Comet Lemmon's dust tail, visible above and around the comet nucleus in off-white, is produced by sun-light reflecting dust shed by the comet's heated nucleus. Flowing and more sculptured, however, is C/2012 F6 (Lemmon)'s blue ion tail, created by the solar wind pushing ions expelled by the nucleus away from the Sun. Also of note is the coma seen surrounding Comet Lemmon's nucleus, tinted green...
  • Astronomy Picture of the Day -- Comet Lemmon and the Deep Sky

    07/20/2013 3:12:16 AM PDT · by SunkenCiv · 6 replies
    NASA ^ | July 20, 2013 | (see photo credit)
    Explanation: Now sweeping high above the ecliptic plane, Comet Lemmon has faded dramatically in planet Earth's night sky as it heads for the outer solar system. Some 16 light-minutes (2 AU) from the Sun, it still sports a greenish coma though, posing on the right in this 4 degree wide telescopic view from last Saturday with deep sky star clusters and nebulae in Cassiopeia. In fact, the rich background skyscape is typical within the boundaries of the boastful northern constellation that lie along the crowded starfields of the Milky Way. Included near center is open star cluster M52 about 5,000...
  • Astronomy Picture of the Day -- Comets Lemmon and PanSTARRS Peaking

    03/05/2013 4:41:44 PM PST · by SunkenCiv · 8 replies
    NASA ^ | March 05, 2013 | (see photo credit)
    Explanation: Two impressive comets will both reach their peak brightness during the next two weeks. Taking advantage of a rare imaging opportunity, both of these comets were captured in the sky together last week over the Atacama desert in South America. Comet C/2012 F6 (Lemmon), visible on the upper left of the above image, is sporting a long tail dominated by glowing green ions. Comet C/2011 L4 (PanSTARRS), visible near the horizon on the lower right, is showing a bright tail dominated by dust reflecting sunlight. The tails of both comets point approximately toward the recently set Sun. Comet Lemmon...
  • Astronomy Picture of the Day -- Sweeping Through Southern Skies

    02/16/2013 8:08:30 PM PST · by SunkenCiv · 9 replies
    NASA ^ | February 16, 2013 | (see photo credit)
    Explanation: For now, Comet Lemmon (C/2012 F6a), and Comet PanSTARRS (C/2011 L4) are sweeping through southern skies. Lemmon's lime green coma and thin tail are near the left edge of this telephoto scene, a single frame from a timelapse video (vimeo here) recorded on February 12, tracking its motion against the background stars. Comet Lemmon's path brought it close to the line-of-sight to prominent southern sky treasures the Small Magellanic Cloud and globular cluster 47 Tucanae (right). Sporting a broader, whitish tail, Comet PanSTARRS appears in later video frames moving through the faint constellation Microscopium. Visible in binoculars and small...
  • Astronomy Picture of the Day -- Comet Lemmon near the South Celestial Pole

    02/07/2013 4:00:05 AM PST · by SunkenCiv · 13 replies
    NASA ^ | February 07, 2013 | (see photo credit)
    Explanation: Currently sweeping through southern skies, Comet Lemmon (C/2012 F6) was named for its discovery last year as part of the Mount Lemmon (Arizona) Survey. Brighter than expected but still just below naked-eye visibility, Comet Lemmon sports a stunning lime green coma and faint divided tail in this telescopic image from February 4. The greenish tint comes from the coma's diatomic C2 gas fluorescing in sunlight. Captured from an observatory near Sydney, Australia, the color composite is constructed from a series of individual exposures registered on the comet. Across the 1 degree wide field of view, the star trails are...