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Explanation: While drifting through the cosmos, a magnificent interstellar dust cloud became sculpted by stellar winds and radiation to assume a recognizable shape. Fittingly named the Horsehead Nebula, it is embedded in the vast and complex Orion Nebula (M42). A potentially rewarding but difficult object to view personally with a small telescope, the above gorgeously detailed image was taken in 2013 in infrared light by the orbiting Hubble Space Telescope in honor of the 23rd anniversary of Hubble's launch. The dark molecular cloud, roughly 1,500 light years distant, is cataloged as Barnard 33 and is seen above primarily because it...

Explanation: Why is Venus so different from Earth? To help find out, Japan launched the robotic Akatsuki spacecraft which entered orbit around Venus late last year after an unplanned five-year adventure around the inner Solar System. Even though Akatsuki has passed its original planned lifetime, the spacecraft and its instruments are operating so well that much of its original mission has been reinstated. In the featured image taken by Akatsuki late last month, Venus was captured in infrared light showing a surprising amount of atmospheric structure on its night side. The vertical orange terminator stripe between night and day is...

Explanation: What can this galaxy tell us about the expansion rate of the universe? Perhaps a lot because UGC 9391, featured, not only contains Cepheid variable stars (red circles) but also a recent Type Ia supernova (blue X). Both types of objects have standard brightnesses, with Cepheids typically being seen relatively nearby, while supernovas are seen much further away. Therefore, this spiral is important because it allows a calibration between the near and distant parts of our universe. Unexpectedly, a recent analysis of new Hubble data from UGC 9391 and several similar galaxies has bolstered previous indications that Cepheids and...

Explanation: It's rare that such different objects are imaged so close together. Such an occasion is occurring now, though, and was captured two days ago in combined parallel exposures from the Canary Islands of Spain. On the lower right, surrounded by a green coma and emanating an unusually split blue ion tail diagonally across the frame, is Comet C/2013 X1 (PanSTARRS). This giant snowball has been falling toward our Sun and brightening since its discovery in 2013. Although Comet PannSTARRS is a picturesque target for long-duration exposures of astrophotography, it is expected to be only barely visible to the unaided...

Science is a process for finding truth in our material world. The blossoming of science occurred in Medieval Europe and continued to flourish until the early part of the last century, almost exclusively in the Western world. This was not coincidental. The combination of the ancient Greek desire for free inquiry combined with the Judeo-Christian belief in an orderly universe and, most vitally, the Judeo-Christian primary value of honesty created in poor, small Europe explosions in thought that the old, rich empires of the East could not achieve. It is also not an accident that the overwhelming majority of early...

Editor's note: This column was co-authored by David Wojick, head of DEWA, a cognitive science and policy analysis consultancy. In an outrageous fit of activism the Portland School Board has banned the teaching of climate science. Of course they have not banned climate science by name, but their new order effectively bans teaching much of what we know about climate, especially the potential role of natural variability in global warming and climate change. In fact they appear to have ruled out the teaching of climate science that is specifically required by the State of Oregon. This is bad news for...

Conservatives care about logic. Liberals care about emotion. Conservatives care about whether a program works or not. Liberals care about how supporting a program makes them feel. Conservatives take the positions they do because they believe they’re best for society. Liberals take the positions they do because they make them feel and look compassionate or superior to hold those positions. Once you understand those basics, it’s very easy to see why both sides hold the positions they do on most issues and to comprehend why there’s so little middle ground. Once you get the mentalities, you can predict where each...

Explanation: Fifty years ago, Surveyor 1 reached the Moon. Launched on May 30, 1966 and landed on June 2, 1966 with the Moon at full phase it became the first US spacecraft to make a soft landing on another world. The first of seven Surveyor missions intended to test the lunar terrain for the planned Apollo landings it sent back over 10,000 images before lunar nightfall on June 14. The total rose to over 11,000 images returned before its second lunar night began on July 13. Surveyor 1 continued to respond from the lunar surface until January 7, 1967. Captured...

Explanation: NGC 4631 is a big beautiful spiral galaxy. Seen edge-on, it lies only 25 million light-years away in the well-trained northern constellation Canes Venatici. The galaxy's slightly distorted wedge shape suggests to some a cosmic herring and to others its popular moniker, The Whale Galaxy. Either way, it is similar in size to our own Milky Way. In this sharp color image, the galaxy's yellowish core, dark dust clouds, bright blue star clusters, and red star forming regions are easy to spot. A companion galaxy, the small elliptical NGC 4627 is just above the Whale Galaxy. Faint star streams...

Explanation: Seen any planets lately? All three planets now shining brightly in the night sky are imaged in these panels, captured last week with the 1 meter telescope at Pic du Midi Observatory in the French Pyrenees. Near opposition and closest to Earth on May 30, Mars is presently offering the best ground-based photo-ops in the last decade. The sharp image finds clouds above the Red Planet's north pole (top) and towering volcanos near its right limb. Saturn reaches its own opposition tonight, its bright rings and gaps clearly revealed in the telescopic portrait. Jupiter is currently highest during the...

Explanation: What star created this huge expanding puffball? Featured here is the first expansion movie ever created for Tycho's supernova remnant, the result of a stellar explosion first recorded over 400 years ago by the famous astronomer Tycho Brahe. The 2-second video is a time-lapse composite of X-ray images taken by the orbiting Chandra X-ray Observatory between the years 2000 and 2015, added to a stock optical frame. The expanding gas cloud is extremely hot, while slightly different expansion speeds have given the cloud a puffy appearance. Although the star that created SN 1572, is likely completely gone, a star...

We like to think of our planet as perfect for life, having met all the conditions we know of for life to exist, flourish and thrive for billions of years. You see, back when the Solar System was younger, the Sun was not just younger, but also cooler. The way a star gets its energy is from nuclear fusion in its core: burning hydrogen into helium in our Sun’s case. Put this all together, and we get an inescapable conclusion: as a star ages and burns through more and more of its fuel, it gives off ever increasing amounts of...

Explanation: To some, it looks like a giant chicken running across the sky. To others, it looks like a gaseous nebula where star formation takes place. Cataloged as IC 2944, the Running Chicken Nebula spans about 100 light years and lies about 6,000 light years away toward the constellation of the Centaur (Centaurus). The featured image, shown in scientifically assigned colors, was captured recently in an 11-hour exposure from a backyard near Melbourne, Australia. Two star clusters are visible: the Pearl Cluster seen on the far left, and Collinder 249 embedded in the nebula's glowing gas. Although difficult to discern...

Explanation: How did the universe evolve from such a smooth beginning? To help understand, computational cosmologists and NASA produced the featured time-lapse animated video depicting a computer simulation of part of the universe. The 100-million light-year simulation starts about 20 million years after the Big Bang and runs until the present. After a smooth beginning, gravity causes clumps of matter to form into galaxies which immediately begin falling toward each other. Soon, many of them condense into long filaments while others violently merge into a huge and hot cluster of galaxies. Investigating of potential universe attributes in simulations like this...

Explanation: Mars will look good in Earth's skies over the next few days -- but not this good. To get a view this amazing, a spacecraft had to actually visit the red planet. Running across the image center, though, is one the largest canyons in the Solar System. Named Valles Marineris, the grand valley extends over 3,000 kilometers long, spans as much as 600 kilometers across, and delves as much as 8 kilometers deep. By comparison, the Earth's Grand Canyon in Arizona, USA is 800 kilometers long, 30 kilometers across, and 1.8 kilometers deep. The origin of the Valles Marineris...

Explanation: The Cat's Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its more familiar outlines are seen in the brighter central region of the nebula in this impressive wide-angle view. But the composite image combines many short and long exposures to also reveal an extremely faint outer halo. At an estimated distance of 3,000 light-years, the faint outer halo is over 5 light-years across. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star. More recently, some planetary nebulae are found to have halos like this...

Explanation: A jewel of the southern sky, the Great Carina Nebula, also known as NGC 3372, spans over 300 light-years, one of our galaxy's largest star forming regions. Like the smaller, more northerly Great Orion Nebula, the Carina Nebula is easily visible to the unaided eye, though at a distance of 7,500 light-years it is some 5 times farther away. This gorgeous telescopic close-up reveals remarkable details of the region's central glowing filaments of interstellar gas and obscuring cosmic dust clouds. The field of view is over 50 light-years across. The Carina Nebula is home to young, extremely massive stars,...

Stephen Hawking, smarter and wiser than many of his colleagues, admits the obvious - that the probability of our universe supporting life is infinitesimally small.  His anything-but-God workaround is simply to propose a near infinite number of universes to solve the problem - if the probability of biological life coming into existence in our universe via purely natural mechanisms is next to nil (which it is) than throw a few septillion parallel universes into the mix and eventually one or two might generate life.  Out of those literally countless universes we just happen to be lucky enough to have been...

Explanation: The prominent ridge of emission featured in this sharp, colorful skyscape is cataloged as IC 5067. Part of a larger emission nebula with a distinctive shape, popularly called The Pelican Nebula, the ridge spans about 10 light-years following the curve of the cosmic pelican's head and neck. This false-color view also translates the pervasive glow of narrow emission lines from atoms in the nebula to a color palette made popular in Hubble Space Telescope images of star forming regions. Fantastic, dark shapes inhabiting the 1/2 degree wide field are clouds of cool gas and dust sculpted by the winds...

Explanation: This sharp telescopic field of view holds two bright galaxies. Barred spiral NGC 5101 (top right) and nearly edge-on system NGC 5078 are separated on the sky by about 0.5 degrees or about the apparent width of a full moon. Found within the boundaries of the serpentine constellation Hydra, both are estimated to be around 90 million light-years away and similar in size to our own large Milky Way galaxy. In fact, if they both lie at the same distance their projected separation would be only 800,000 light-years or so. That's easily less than half the distance between the...