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Jul 31, 2019

IC 1795: The Fishhead Nebula IC 1795: The Fishhead Nebula


To some, this nebula looks like the head of a fish. However, this colorful cosmic portrait really features glowing gas and obscuring dust clouds in IC 1795, a star forming region in the northern constellation Cassiopeia. The nebula's colors were created by adopting the Hubble color palette for mapping narrow emission from oxygen, hydrogen, and sulfur atoms to blue, green and red colors, and further blending the data with images of the region recorded through broadband filters. Not far on the sky from the famous Double Star Cluster in Perseus, IC 1795 is itself located next to IC 1805, the Heart Nebula, as part of a complex of star forming regions that lie at the edge of a large molecular cloud. Located just over 6,000 light-years away, the larger star forming complex sprawls along the Perseus spiral arm of our Milky Way Galaxy. At that distance, this picture would span about 70 light-years across IC 1795. via NASA https://ift.tt/2YbkBbE

Jul 30, 2019

Star Forming Region NGC 3582 without Stars Star Forming Region NGC 3582 without Stars


What's happening in the Statue of Liberty nebula? Bright stars and interesting molecules are forming and being liberated. The complex nebula resides in the star forming region called RCW 57, and besides the iconic monument, to some looks like a flying superhero or a weeping angel. By digitally removing the stars, this image showcases dense knots of dark interstellar dust, fields of glowing hydrogen gas ionized by these stars, and great loops of gas expelled by dying stars. A detailed study of NGC 3576, also known as NGC 3582 and NGC 3584, uncovered at least 33 massive stars in the end stages of formation, and the clear presence of the complex carbon molecules known as polycyclic aromatic hydrocarbons (PAHs). PAHs are thought to be created in the cooling gas of star forming regions, and their development in the Sun's formation nebula five billion years ago may have been an important step in the development of life on Earth. via NASA https://ift.tt/2GAwOfk

Jul 22, 2019

HDR: Earths Circular Shadow on the Moon HDR: Earths Circular Shadow on the Moon


What could create such a large circular shadow on the Moon? The Earth. Last week's full Moon -- the Buck Moon -- was so full that it fell almost exactly in a line with the Sun and the Earth. When that happens the Earth casts its shadow onto the Moon. The circularity of the Earth's shadow on the Moon was commented on by Aristotle and so has been noticed since at least the 4th century BC. What's new is humanity's ability to record this shadow with such high dynamic range (HDR). The featured HDR composite of last week's partial lunar eclipse combines 15 images and include an exposure as short as 1/400th of a second -- so as not to overexpose the brightest part -- and an exposure that lasted five seconds -- to bring up the dimmest part. This dimmest part -- inside Earth's umbra -- is not completely dark because some light is refracted through the Earth's atmosphere onto the Moon. A total lunar eclipse will occur next in 2021 May. via NASA https://ift.tt/2JTAABc

Jul 21, 2019

Moonquakes Surprisingly Common Moonquakes Surprisingly Common


Why are there so many moonquakes? Analyses of seismometers left on the moon by the Apollo moon landings reveals a surprising number of moonquakes occurring within 100 kilometers of the surface. In fact, 62 moonquakes were detected in data recorded between 1972 and 1977. Many of these moonquakes are not only strong enough to move furniture in a lunar apartment, but the stiff rock of the moon continues to vibrate for many minutes, significantly longer than the softer rock earthquakes on Earth. The cause of the moonquakes remains unknown, but a leading hypothesis is the collapse of underground faults. Regardless of the source, future moon dwellings need to be built to withstand the frequent shakings. Pictured here 50 years ago today, Apollo 11 astronaut Buzz Aldrin stands beside a recently deployed lunar seismometer, looking back toward the lunar landing module. via NASA https://ift.tt/2O7yD9s

Jul 18, 2019

Shadowed Moon and Mountain Shadowed Moon and Mountain


On July 16 the Moon celebrated the 50th anniversary of the launch of Apollo 11 with a lunar eclipse visible from much of planet Earth. In this view part of the lunar disk is immersed in Earth's dark, reddened umbral shadow. Near the maximum eclipse phase, it just touches down along a mountain ridge. The rugged Tyrolean nightscape was recorded after moonrise south of Innsbruck, Austria with a dramatically lit communication tower along the ridgeline. Of course eclipses rarely travel alone. This partial lunar eclipse was at the Full Moon following July 2nd's New Moon and total eclipse of the Sun. via NASA https://ift.tt/2xUo7rq

Jul 17, 2019

Apollo 11: Descent to the Moon Apollo 11: Descent to the Moon


It had never been done before. But with the words "You're Go for landing", 50 years ago this Saturday, Apollo 11 astronauts Aldrin and Armstrong were cleared to make the first try. The next few minutes would contain more than a bit of drama, as an unexpected boulder field and an unacceptably sloping crater loomed below. With fuel dwindling, Armstrong coolly rocketed the lander above the lunar surface as he looked for a clear and flat place to land. With only seconds of fuel remaining, and with the help of Aldrin and mission control calling out data, Armstrong finally found a safe spot -- and put the Eagle down. Many people on Earth listening to the live audio felt great relief on hearing "The Eagle has landed", and great pride knowing that for the first time ever, human beings were on the Moon. Combined in the featured descent video are two audio feeds, a video feed similar to what the astronauts saw, captions of the dialog, and data including the tilt of the Eagle lander. The video concludes with the panorama of the lunar landscape visible outside the Eagle. A few hours later, hundreds of millions of people across planet Earth, drawn together as a single species, watched fellow humans walk on the Moon. via NASA https://ift.tt/2NYuZyQ

Jul 16, 2019

Apollo 11 Launches Humans to the Moon Apollo 11 Launches Humans to the Moon


Everybody saw the Moon. Nobody had ever been there. Humans across planet Earth watched in awe 50 years ago today as a powerful Saturn V rocket attempted to launch humans -- to the Moon. Some in space flight guessed that the machinery was so complex, that so many things had to go right for it to work, that Apollo 11 would end up being another useful dress rehearsal for a later successful Moon-landing mission. But to the Moon they went. The featured video starts by showing astronauts Aldrin, Armstrong, and Collins making their way to the waiting rocket. As the large and mighty Saturn V launched, crowds watched from Cape Canaveral in Florida, USA and on television around the world. The events that unfolded over the next few days, including a dramatic moon walk 50 years ago this Saturday, will forever be remembered as a milestone in human history and an unrivaled demonstration of human ingenuity. This week, many places around the world are planning celebrations of the 50th anniversary of the first humans landing on the Moon. via NASA https://ift.tt/2k5dHll

Jul 13, 2019

The Eagle Rises The Eagle Rises


Get out your red/blue glasses and check out this stereo view from lunar orbit. The 3D anaglyph was created from two photographs (AS11-44-6633, AS11-44-6634) taken by astronaut Michael Collins during the 1969 Apollo 11 mission. It features the lunar module ascent stage, dubbed The Eagle, rising to meet the command module in lunar orbit on July 21. Aboard the ascent stage are Neil Armstrong and Buzz Aldrin, the first to walk on the Moon. The smooth, dark area on the lunar surface is Mare Smythii located just below the equator on the extreme eastern edge of the Moon's near side. Poised beyond the lunar horizon is our fair planet Earth. via NASA https://ift.tt/2ScCK2n

Jul 10, 2019

4000 Exoplanets 4000 Exoplanets


Over 4000 planets are now known to exist outside our Solar System. Known as exoplanets, this milestone was passed last month, as recorded by NASA's Exoplanet Archive. The featured video highlights these exoplanets in sound and light, starting chronologically from the first confirmed detection in 1992. The entire night sky is first shown compressed with the central band of our Milky Way Galaxy making a giant U. Exoplanets detected by slight jiggles in their parents-star's colors (radial velocity) appear in pink, while those detected by slight dips in their parent star's brightness (transit) are shown in purple. Further, those exoplanets imaged directly appear in orange, while those detected by gravitationally magnifying the light of a background star (microlensing) are shown in green. The faster a planet orbits its parent star, the higher the accompanying tone played. The retired Kepler satellite has discovered about half of these first 4000 exoplanets in just one region of the sky, while the new TESS mission is on track to find even more, all over the sky, orbiting the brightest nearby stars. Finding exoplanets not only helps humanity to better understand the potential prevalence of life elsewhere in the universe, but also how our Earth and Solar System were formed. via NASA https://ift.tt/2YSAiRv

Jul 9, 2019

Birds During a Total Solar Eclipse Birds During a Total Solar Eclipse


What do birds do during a total solar eclipse? Darkness descends more quickly in a total eclipse than during sunset, but returns just as quickly -- and perhaps unexpectedly to the avians -- just a few minutes later. Stories about the unusual behavior of birds during eclipses have been told for centuries, but bird reactions were recorded and studied systematically by citizen scientists participating in an eBird project during the total solar eclipse that crossed the USA in 2017 August. Although some unusual behaviors were observed, many observers noted birds acting like it was dusk and either landing or flying low to the ground. Radar confirmed a significant decrease in high-flying birds and insects during and just after totality. Conversely, several sightings of normally nocturnal birds were reported. Pictured, a flock of birds in La Serena, Chile flew through the air together during the total solar eclipse that crossed South America last week. The photographer captured the scene in frames from an eclipse video. The next total solar eclipse in 2020 December will also cross South America, while in 2024 April a total solar eclipse will cross North America from Mexico through New England, USA. via NASA https://ift.tt/2XBq1aP

Jul 8, 2019

The Galactic Center in Radio from MeerKAT The Galactic Center in Radio from MeerKAT


What's happening at the center of our galaxy? It's hard to tell with optical telescopes since visible light is blocked by intervening interstellar dust. In other bands of light, though, such as radio, the galactic center can be imaged and shows itself to be quite an interesting and active place. The featured picture shows the inaugural image of the MeerKAT array of 64 radio dishes just completed in South Africa. Spanning four times the angular size of the Moon (2 degrees), the image is impressively vast, deep, and detailed. Many known sources are shown in clear detail, including many with a prefix of Sgr, since the Galactic Center is in the direction of the constellation Sagittarius. In our Galaxy's Center lies Sgr A, found here just to the right of the image center, which houses the Milky Way's central supermassive black hole. Other sources in the image are not as well understood, including the Arc, just to the left of Sgr A, and numerous filamentary threads. Goals for MeerKAT include searching for radio emission from neutral hydrogen emitted in a much younger universe and brief but distant radio flashes. via NASA https://ift.tt/2G1vK3w

Jul 6, 2019

8 Minute and 30 Second Eclipse 8 Minute and 30 Second Eclipse


The total phase of the July 2nd solar eclipse lasted about 4 minutes and 30 seconds at the point of maximum eclipse. On the surface of planet Earth, that was about 600 nautical miles north of Easter Island in the Southern Pacific Ocean. But from 37,000 feet above, on a charter flight intercepting the Moon's shadow, the Moon could be seen to completely block the Sun for about 8 minutes and 30 seconds. With a tailwind at the mid-eclipse intercept point, the plane was traveling around 488 nautical miles per hour chasing along the Moon's shadow track. From above the clouds this wide-field image of the totally eclipsed Sun and shimmering solar corona over the wing records the spectacular view from a window seat on the sunward side of the aircraft. via NASA https://ift.tt/2xvXhFF

Jul 5, 2019

La Silla Eclipse Sequence La Silla Eclipse Sequence


The road to the high mountaintop La Silla Observatory in the Chilean Atacama Desert also led in to the path of July 2nd's total solar eclipse. Recorded at regular intervals before and after the total eclipse phase, the frames in this composite sequence include the moment the Moon's dark shadow fell across some of planet Earth's advanced large telescopes. The dreamlike view looks west toward the setting Sun and the approaching Moon shadow. In fact La Silla was a little north of the shadow track's center line, so the region's stunning, clear skies are slightly brighter to the north (right) in the scene. via NASA https://ift.tt/2JdtRTC

Jul 4, 2019

In the Shadow of the Moon In the Shadow of the Moon


On July 2 denizens of planet Earth could stand in the Moon's dark umbral shadow during South America's 2019 total solar eclipse. It first touched down in the Southern Pacific Ocean, east of New Zealand. Racing toward the east along a narrow track, the shadow of the Moon made landfall along the Chilean coast with the Sun low on the western horizon. Captured in the foreground here are long shadows still cast by direct sunlight though, in the final moments before totality began. While diffraction spikes are from the camera lens aperture, the almost totally eclipsed Sun briefly shone like a beautiful diamond ring in the clear, darkened sky. via NASA https://ift.tt/2FQcOVu

Jul 3, 2019

Robotic Dragonfly Selected to Fly Across Titan Robotic Dragonfly Selected to Fly Across Titan


If you could fly across Titan, what would you see? To find out and to better explore this exotic moon of Saturn, NASA recently green-lighted Dragonfly, a mission to Titan with plans to deploy a helicopter-like drone. Saturn's moon Titan is one of the largest moons in the Solar System and the only moon known to have a thick atmosphere and changing hydrocarbon lakes. After development, building, testing, and launch, Dragonfly is currently scheduled to reach Titan in 2034. The featured animated video envisions Dragonfly arriving at Titan, beginning its airborne exploration, landing to establishing a radio link back to Earth, and then continuing on to another trans-Titanian flight. It is hoped that Dragonfly will not only help humanity better understanding Titan's weather, chemistry, and changing landscape, but also bolster humanity's understanding of how life first developed on our young Earth. via NASA https://ift.tt/2Yt4pP5

Jul 1, 2019

The Big Corona The Big Corona


Most photographs don't adequately portray the magnificence of the Sun's corona. Seeing the corona first-hand during a total solar eclipse is unparalleled. The human eye can adapt to see coronal features and extent that average cameras usually cannot. Welcome, however, to the digital age. The featured central image digitally combined short and long exposures that were processed to highlight faint and extended features in the corona of the total solar eclipse that occurred in August of 2017. Clearly visible are intricate layers and glowing caustics of an ever changing mixture of hot gas and magnetic fields in the Sun's corona. Looping prominences appear bright pink just past the Sun's limb. Faint details on the night side of the New Moon can even be made out, illuminated by sunlight reflected from the dayside of the Full Earth. Images taken seconds before and after the total eclipse show glimpses of the background Sun known as Baily's Beads and Diamond Ring. Tomorrow, a new total solar eclipse will be visible from parts of South America. via NASA https://ift.tt/2NoGUW8