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Keyword: astronomy

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  • Astronomy Picture of the Day -- Milky Way Over Quiver Tree Forest

    05/15/2016 3:40:02 PM PDT · by SunkenCiv · 8 replies
    NASA ^ | Sunday, May 15, 2016 | (see photo credit)
    Explanation: In front of a famous background of stars and galaxies lies some of Earth's more unusual trees. Known as quiver trees, they are actually succulent aloe plants that can grow to tree-like proportions. The quiver tree name is derived from the historical usefulness of their hollowed branches as dart holders. Occurring primarily in southern Africa, the trees pictured in the above 16-exposure composite are in Quiver Tree Forest located in southern Namibia. Some of the tallest quiver trees in the park are estimated to be about 300 years old. Behind the trees is light from the small town of...
  • Astronomy Picture of the Day -- Falcon 9 and Milky Way

    05/14/2016 1:08:21 PM PDT · by SunkenCiv · 9 replies
    NASA ^ | Saturday, May 14, 2016 | (see photo credit)
    Explanation: On May 6, the after midnight launch of a SpaceX Falcon 9 rocket lit up dark skies over Merritt Island, planet Earth. Its second stage bound for Earth orbit, the rocket's arc seems to be on course for the center of the Milky Way in this pleasing composite image looking toward the southeast. Two consecutive exposures made with camera fixed to a tripod were combined to follow rocket and home galaxy. A 3 minute long exposure at low sensitivity allowed the rocket's first stage burn to trace the bright orange arc and a 30 second exposure at high sensitivity...
  • Astronomy Picture of the Day -- ISS and Mercury Too

    05/14/2016 1:03:04 PM PDT · by SunkenCiv · 4 replies
    NASA ^ | Friday, May 13, 2016 | (see photo credit)
    Explanation: Transits of Mercury are relatively rare. Monday's leisurely 7.5 hour long event was only the 2nd of 14 Mercury transits in the 21st century. If you're willing to travel, transits of the International Space Station can be more frequent though, and much quicker. This sharp video frame composite was taken from a well-chosen location in Philadelphia, USA. It follows the space station, moving from upper right to lower left, as it crossed the Sun's disk in 0.6 seconds. Mercury too is included as the small, round, almost stationary silhouette just below center. In apparent size, the International Space Station...
  • Astronomy Picture of the Day -- A Transit of Mercury

    05/12/2016 4:52:01 AM PDT · by SunkenCiv · 9 replies
    NASA ^ | Thursday, May 12, 2016 | (see photo credit)
    Explanation: On May 9, the diminutive disk of Mercury spent about seven and a half hours crossing in front of the Sun as viewed from the general vicinity of Earth. It was the second of 14 transits of the Solar System's innermost planet in the 21st century. Captured from Fulham, London, England, planet Earth the tiny silhouette shares the enormous solar disk with prominences, filaments, and active regions in this sharp image. But Mercury's round disk (left of center) appears to be the only dark spot, despite the planet-sized sunspots scattered across the Sun. Made with an H-alpha filter that...
  • Astronomy Picture of the Day -- A Mercury Transit Music Video from SDO

    05/11/2016 1:52:06 PM PDT · by SunkenCiv · 3 replies
    NASA ^ | Wednesday, May 11, 2016 | (see photo credit)
    Explanation: What's that small black dot moving across the Sun? Mercury. Possibly the clearest view of Mercury crossing in front of the Sun earlier this week was from Earth orbit. The Solar Dynamics Observatory obtained an uninterrupted vista recording it not only in optical light but also in bands of ultraviolet light. Featured here is a composite movie of the crossing set to music. Although the event might prove successful scientifically for better determining components of Mercury' ultra-thin atmosphere, the event surely proved successful culturally by involving people throughout the world in observing a rare astronomical phenomenon. Many spectacular images...
  • Astronomy Picture of the Day -- Saturn and Mars visit Milky Way Star Clouds

    05/10/2016 4:57:55 AM PDT · by SunkenCiv · 4 replies
    NASA ^ | Tuesday, May 10, 2016 | (see photo credit)
    Explanation: Planets, stars, nebulas and a galaxy -- this impressive image has them all. Closest to home are the two planets Mars (right) and Saturn (center), visible as the two bright orange spots in the upper half of the featured image. On the central right are the colorful Rho Ophiuchus star clouds featuring the bright orange star Antares lined up below Mars. These interstellar clouds contain both red emission nebulas and blue reflection nebulas. At the top right of the image is the Blue Horsehead reflection nebula. On the lower left are many dark absorption nebulas that extend from the...
  • Astronomy Picture of the Day -- Webb Telescope Mirror Rises after Assembly

    05/10/2016 4:54:25 AM PDT · by SunkenCiv · 10 replies
    NASA ^ | Monday, May 09, 2016 | (see photo credit)
    Explanation: Move over Hubble -- here comes the James Webb Space Telescope (JWST). JWST promises to be the new most powerful telescope in space. In the last month, the 18-segment gold-plated primary mirror for JWST was unveiled. In the featured time-lapse video taken last week, the 6.5-meter diameter mirror was raised to a vertical position. The dramatic 30-second sequence shows NASA engineers monitoring the test as room lights glint brightly off the mirror's highly reflective surface. The beryllium mirrors have been coated with a thin film of gold to make them more reflective to infrared light. The science goals of...
  • Astronomy Picture of the Day -- Mercury's Transit: An Unusual Spot on the Sun

    05/10/2016 4:51:35 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | Sunday, May 08, 2016 | (see photo credit)
    Explanation: What's that dot on the Sun? If you look closely, it is almost perfectly round. The dot is the result of an unusual type of solar eclipse that occurred in 2006. Usually it is the Earth's Moon that eclipses the Sun. This time, the planet Mercury took a turn. Like the approach to New Moon before a solar eclipse, the phase of Mercury became a continually thinner crescent as the planet progressed toward an alignment with the Sun. Eventually the phase of Mercury dropped to zero and the dark spot of Mercury crossed our parent star. The situation could...
  • Astronomy Picture of the Day -- Three Worlds for TRAPPIST-1

    05/07/2016 5:39:19 PM PDT · by SunkenCiv · 3 replies
    NASA ^ | Saturday, May 07, 2016 | (see photo credit)
    Explanation: Three new found worlds orbit the ultracool dwarf star TRAPPIST-1, a mere 40 light-years away. Their transits were first detected by the Belgian robotic TRAnsiting Planets and Planetesimals Small Telescope, TRAPPIST, at ESO's La Silla Observatory in Chile. The newly discovered exoplanets are all similar in size to Earth. Because they orbit very close to their faint, tiny star they could also have regions where surface temperatures allow for the presence of liquid water, a key ingredient for life. Their tantalizing proximity to Earth makes them prime candidates for future telescopic explorations of the atmospheres of these potentially habitable...
  • Mars and Earth are getting closer (for now)

    05/06/2016 1:06:47 PM PDT · by BenLurkin · 13 replies
    The red planet will soon be closer to Earth that it has been in 11 years: On May 30, Mars will be about 46.8 million miles (75.3 million kilometers) from Earth. Yes, that’s still a long way off, but sometimes Mars is 249 million miles (400 million kilometers) from Earth. What does this close approach mean for sky watchers? It means Mars will appear bigger and brighter from May 18 until June 3, according to NASA. But you don’t have to wait. Mars already is putting on a spectacular show in the early morning sky. And you don’t need a...
  • Astronomy Picture of the Day -- NGC 7023: The Iris Nebula

    05/06/2016 5:51:52 AM PDT · by SunkenCiv · 5 replies
    NASA ^ | Friday, May 06, 2016 | (see photo credit)
    Explanation: These cosmic clouds have blossomed 1,300 light-years away, in the fertile starfields of the constellation Cepheus. Called the Iris Nebula, NGC 7023 is not the only nebula to evoke the imagery of flowers, though. Still, this deep telescopic image shows off the Iris Nebula's range of colors and symmetries, embedded in surrounding fields of interstellar dust. Within the Iris itself, dusty nebular material surrounds a hot, young star. The dominant color of the brighter reflection nebula is blue, characteristic of dust grains reflecting starlight. Central filaments of the reflection nebula glow with a faint reddish photoluminesence as some dust...
  • Astronomy Picture of the Day -- The SONG and the Hunter

    05/05/2016 6:49:49 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | Thursday, May 05, 2016 | (see photo credit)
    Explanation: Near first quarter, the Moon in March lights this snowy, rugged landscape, a view across the top of Tenerife toward La Palma in the Canary Islands Spanish archipelago. The large Teide volcano, the highest point in Spain, looms over the horizon. Shining above are familiar bright stars of Orion, the Hunter. Adding to the dreamlike scene is the 1 meter diameter prototype telescope of the global network project called the Stellar Observations Network Group or SONG. The SONG's fully robotic observatory was captured during the 30 second exposure while the observatory dome, with slit open, was rotated across the...
  • Astronomy Picture of the Day -- A Mercury Transit Sequence

    05/03/2016 11:41:56 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | Wednesday, May 04, 2016 | (see photo credit)
    Explanation: This coming Monday, Mercury will cross the face of the Sun, as seen from Earth. Called a transit, the last time this happened was in 2006. Because the plane of Mercury's orbit is not exactly coincident with the plane of Earth's orbit, Mercury usually appears to pass over or under the Sun. The above time-lapse sequence, superimposed on a single frame, was taken from a balcony in Belgium shows the entire transit of 2003 May 7. The solar crossing lasted over five hours, so that the above 23 images were taken roughly 15 minutes apart. The north pole of...
  • Astronomy Picture of the Day -- Aurora over Sweden

    05/03/2016 12:44:34 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | Tuesday, May 03, 2016 | (see photo credit)
    Explanation: It was bright and green and stretched across the sky. This striking aurora display was captured last month just outside of Östersund, Sweden. Six photographic fields were merged to create the featured panorama spanning almost 180 degrees. Particularly striking aspects of this aurora include its sweeping arc-like shape and its stark definition. Lake Storsjön is seen in the foreground, while several familiar constellations and the star Polaris are visible through the aurora, far in the background. Coincidently, the aurora appears to avoid the Moon visible on the lower left. The aurora appeared a day after a large hole opened...
  • Astronomy Picture of the Day -- Crossing Mars

    05/03/2016 12:36:30 AM PDT · by SunkenCiv · 5 replies
    NASA ^ | Monday, May 02, 2016 | (see photo credit)
    Explanation: Where is NASA's rover Curiosity going on Mars? Its geographical goals are on the slopes of Mount Sharp, whose peak is seen in the background on the right. A key scientific goal, however, remains to better assess when and where conditions on Mars were once suitable for life, in particular microbial life. To further this goal, Curiosity was directed to cross the rugged terrain of Nautkluft Plateau, visible in the featured image on the foreground left. Curiosity is crossing toward smoother uphill sites with rocks containing hematite and sulfates, sites that could give the rolling rover new clues on...
  • Astronomy Picture of the Day -- Contemplating the Sun

    05/03/2016 12:35:51 AM PDT · by SunkenCiv · 5 replies
    NASA ^ | Sunday, May 01, 2016 | (see photo credit)
    Explanation: Have you contemplated your home star recently? Featured here, a Sun partially eclipsed on the top left by the Moon is also seen eclipsed by earthlings contemplating the eclipse below. The spectacular menagerie of silhouettes was taken in 2012 from the Glen Canyon National Recreation Area near Page, Arizona, USA, where park rangers and astronomers expounded on the unusual event to interested gatherers. Also faintly visible on the Sun's disk, just to the lower right of the dark Moon's disk, is a group of sunspots. Although a partial solar eclipse by the Moon is indeed a good chance to...
  • Scientists discover three 'potentially habitable' planets

    05/02/2016 10:19:44 AM PDT · by Phlap · 40 replies
    Yahoo ^ | 05/02/2016 | Marlowe Hood
    An international team of scientists said Monday they had discovered a trio of Earth-like planets that are the best bet so far for finding life outside our solar system. The three orbit an ultracool dwarf star a mere 39 light years away, and are likely comparable in size and temperature to Earth and Venus, they reported in a study, published in Nature.
  • Astronomy Picture of the Day -- Moon over Makemake

    04/30/2016 2:03:40 PM PDT · by SunkenCiv · 8 replies
    NASA ^ | Saturday, April 30, 2016 | (see photo credit)
    Explanation: Makemake, second brightest dwarf planet of the Kuiper belt, has a moon. Nicknamed MK2, Makemake's moon reflects sunlight with a charcoal-dark surface, about 1,300 times fainter than its parent body. Still, it was spotted in Hubble Space Telescope observations intended to search for faint companions with the same technique used to find the small satellites of Pluto. Just as for Pluto and its satellites, further observations of Makemake and orbiting moon will measure the system's mass and density and allow a broader understanding of the distant worlds. About 160 kilometers (100 miles) across compared to Makemake's 1,400 kilometer diameter,...
  • Astronomy Picture of the Day -- Fermi's Gamma-ray Moon

    04/29/2016 5:07:09 AM PDT · by SunkenCiv · 20 replies
    NASA ^ | Friday, April 29, 2016 | (see photo credit)
    Explanation: If you could only see gamma-rays, photons with up to a billion or more times the energy of visible light, the Moon would be brighter than the Sun! That startling notion underlies this novel image of the Moon, based on data collected by the Fermi Gamma-ray Space Telescope's Large Area Telescope (LAT) instrument during its first seven years of operation (2008-2015). Fermi's gamma-ray vision doesn't distinguish details on the lunar surface, but a gamma-ray glow consistent with the Moon's size and position is clearly found at the center of the false color map. The brightest pixels correspond to the...
  • Astronomy Picture of the Day -- A Dust Angel Nebula

    04/28/2016 4:21:53 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | Thursday, April 28, 2016 | (see photo credit)
    Explanation: The combined light of stars along the Milky Way are reflected by these cosmic dust clouds that soar some 300 light-years or so above the plane of our galaxy. Dubbed the Angel Nebula, the faint apparition is part of an expansive complex of dim and relatively unexplored, diffuse molecular clouds. Commonly found at high galactic latitudes, the dusty galactic cirrus can be traced over large regions toward the North and South Galactic poles. Along with the refection of starlight, studies indicate the dust clouds produce a faint reddish luminescence, as interstellar dust grains convert invisible ultraviolet radiation to visible...