M33: Triangulum Galaxy M33: Triangulum Galaxy

The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 is itself thought to be a satellite of the Andromeda Galaxy and astronomers in these two galaxies would likely have spectacular views of each other's grand spiral star systems. As for the view from planet Earth, this sharp composite image nicely shows off M33's blue star clusters and pinkish star forming regions along the galaxy's loosely wound spiral arms. In fact, the cavernous NGC 604 is the brightest star forming region, seen here at about the 1 o'clock position from the galaxy center. Like M31, M33's population of well-measured variable stars have helped make this nearby spiral a cosmic yardstick for establishing the distance scale of the Universe. via NASA http://ift.tt/2d8hsSb

The North and South of Jupiter The North and South of Jupiter

A wide, looping orbit brought Juno close to Jupiter on August 27. As the spacecraft swung around the giant planet's poles JunoCam acquired these premier direct polar views, a change from the usual nearly equatorial perspective of outbound spacecraft and the telescopes of planet Earth. The sunlit side of Jupiter's north polar region (left) was imaged about 125,000 kilometers from the cloud tops, two hours before Juno's closest approach. An hour after close approach the south polar region was captured from 94,500 kilometers away. Strikingly different from the alternating light-colored zones and darker belts girdling more familiar equatorial regions, the polar region clouds appear more convoluted and mottled by many clockwise and counterclockwise rotating storm systems. Another 35 close orbital flybys are planned during the Juno mission. via NASA http://ift.tt/2cZvkxY

The Wide and Deep Lagoon The Wide and Deep Lagoon

Ridges of glowing interstellar gas and dark dust clouds inhabit the turbulent, cosmic depths of the Lagoon Nebula. Also known as M8, the bright star forming region is about 5,000 light-years distant. But it still makes for a popular stop on telescopic tours of the constellation Sagittarius, toward the center of our Milky Way Galaxy. Dominated by the telltale red emission of ionized hydrogen atoms recombining with stripped electrons, this stunning, deep view of the Lagoon is nearly 100 light-years across. Right of center, the bright, compact, hourglass shape is gas ionized and sculpted by energetic radiation and extreme stellar winds from a massive young star. In fact, the many bright stars of open cluster NGC 6530 drift within the nebula, just formed in the Lagoon several million years ago. via NASA http://ift.tt/2cJXEnU

Eclipse to Sunset Eclipse to Sunset

September's eclipse of the Sun is documented in the 68 frames of this timelapse composite. Starting at 1pm local time a frame every 4 minutes follow's the progress of the New Moon across the solar disk. Taken near the centerline of the narrow eclipse path, the series of exposures ends with a golden sunset. Balanced rock cairns in the foreground line a beach on the southern side of Reunion Island in the Indian Ocean, near the village of Etang-Salé. Of course, the close balance in apparent size creates drama in eclipses of the Sun by the Moon as seen from planet Earth. In an annular eclipse, the Moon's silhouette is just small enough to show the solar disk as a narrow ring-of-fire at maximum eclipse phase. via NASA http://ift.tt/2cjUQNE

The Whirlpool Galaxy and Beyond The Whirlpool Galaxy and Beyond

Follow the handle of the Big Dipper away from the dipper's bowl, until you get to the handle's last bright star. Then, just slide your telescope a little south and west and you might find this stunning pair of interacting galaxies, the 51st entry in Charles Messier's famous catalog. Perhaps the original spiral nebula, the large galaxy with well defined spiral structure is also cataloged as NGC 5194. Its spiral arms and dust lanes clearly sweep in front of its companion galaxy (left), NGC 5195. The pair are about 31 million light-years distant and officially lie within the angular boundaries of the small constellation Canes Venatici. Though M51 looks faint and fuzzy to the human eye, the above long-exposure, deep-field image taken earlier this year shows much of the faint complexity that actually surrounds the smaller galaxy. Thousands of the faint dots in background of the featured image are actually galaxies far across the universe. via NASA http://ift.tt/2ckvJbO

Little Planet Astro Camp Little Planet Astro Camp

Day and night on this little planet look a lot like day and night on planet Earth. In fact, the images used to construct the little planet projection, a digitally warped and stitched mosaic covering 360x180 degrees, were taken during day and night near Tarján, Hungary, planet Earth. They span a successful 33-hour-long photo experiment at July's Hungarian Astronomical Association Astro Camp. The time-series composite follows the solar disk in 20 minute intervals from sunrise to sunset and over six hours of star trails in the northern night sky centered on the North Celestial Pole near bright star Polaris. The orbiting International Space Station traced the offset arc across the northern night. Below the little planet's nightside horizon, red light lamps of fellow astro-campers left the night-long, dancing trails. via NASA http://ift.tt/2bPv53O

Annular Solar Eclipse over New Mexico Annular Solar Eclipse over New Mexico

What is this person doing? In 2012 an annular eclipse of the Sun was visible over a narrow path that crossed the northern Pacific Ocean and several western US states. In an annular solar eclipse, the Moon is too far from the Earth to block out the entire Sun, leaving the Sun peeking out over the Moon's disk in a ring of fire. To capture this unusual solar event, an industrious photographer drove from Arizona to New Mexico to find just the right vista. After setting up and just as the eclipsed Sun was setting over a ridge about 0.5 kilometers away, a person unknowingly walked right into the shot. Although grateful for the unexpected human element, the photographer never learned the identity of the silhouetted interloper. It appears likely, though, that the person is holding a circular device that would enable them to get their own view of the eclipse. The shot was taken at sunset on 2012 May 20 at 7:36 pm local time from a park near Albuquerque, New Mexico, USA. Tomorrow another annular solar eclipse will become visible, this time along a path crossing Africa and Madagascar. via NASA http://ift.tt/2bC06Ln

Aurora over Icelandic Fault Aurora over Icelandic Fault

Admire the beauty but fear the beast. The beauty is the aurora overhead, here taking the form of great green spiral, seen between picturesque clouds with the bright Moon to the side and stars in the background. The beast is the wave of charged particles that creates the aurora but might, one day, impair civilization. Exactly this week in 1859, following notable auroras seen all across the globe, a pulse of charged particles from a coronal mass ejection (CME) associated with a solar flare impacted Earth's magnetosphere so forcefully that they created the Carrington Event. A relatively direct path between the Sun and the Earth might have been cleared by a preceding CME. What is sure is that the Carrington Event compressed the Earth's magnetic field so violently that currents were created in telegraph wires so great that many wires sparked and gave telegraph operators shocks. Were a Carrington-class event to impact the Earth today, speculation holds that damage might occur to global power grids and electronics on a scale never yet experienced. The featured aurora was imaged last week over Thingvallavatn Lake in Iceland, a lake that partly fills a fault that divides Earth's large Eurasian and North American tectonic plates. via NASA http://ift.tt/2byz7QQ

Abell 370: Galaxy Cluster Gravitational Lens Abell 370: Galaxy Cluster Gravitational Lens

What is that strange arc? While imaging the cluster of galaxies Abell 370, astronomers had noted an unusual arc to the right of many cluster galaxies. Although curious, one initial response was to avoid commenting on the arc because nothing like it had ever been noted before. In the mid-1980s, however, better images allowed astronomers to identify the arc as a prototype of a new kind of astrophysical phenomenon -- the gravitational lens effect of entire cluster of galaxies on background galaxies. Today, we know that this arc actually consists of two distorted images of a fairly normal galaxy that happened to lie far behind the huge cluster. Abell 370's gravity caused the background galaxies' light -- and others -- to spread out and come to the observer along multiple paths, not unlike a distant light appears through the stem of a wine glass. In mid-July of 2009, astronomers used the then just-upgraded Hubble Space Telescope to image Abell 370 and its gravitational lens images in unprecedented detail. Almost all of the yellow images featured here are galaxies in the Abell 370 cluster. An astute eye can pick up many strange arcs and distorted arclets, however, that are actually images of more distant galaxies. Studying Abell 370 and its images gives astronomers a unique window into the distribution of normal and dark matter in galaxy clusters and the universe. via NASA http://ift.tt/2bXXoiK

Lunar Orbiter Earthset Lunar Orbiter Earthset

August 10th was the 50th anniversary of the launch of Lunar Orbiter 1. It was the first of five Lunar Orbiters intended to photograph the Moon's surface to aid in the selection of future landing sites. That spacecraft's camera captured the data used in this restored, high-resolution version of its historic first image of Earth from the Moon on August 23, 1966 while on its 16th lunar orbit. Hanging almost stationary in the sky when viewed from the lunar surface, Earth appears to be setting beyond the rugged lunar horizon from the perspective of the orbiting spacecraft. Two years later, the Apollo 8 crew would record a more famous scene in color: Earthrise from lunar orbit. via NASA http://ift.tt/2chQLuW