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Explanation: Magnificent island universe NGC 2403 stands within the boundaries of the long-necked constellation Camelopardalis. Some 10 million light-years distant and about 50,000 light-years across, the spiral galaxy also seems to have more than its fair share of giant star forming HII regions, marked by the telltale reddish glow of atomic hydrogen gas. The giant HII regions are energized by clusters of hot, massive stars that explode as bright supernovae at the end of their short and furious lives. A member of the M81 group of galaxies, NGC 2403 closely resembles another galaxy with an abundance of star forming regions...

One such mystery confronting solar dynamics is exactly what drives the periodicity related to the solar cycle. Follow our star with a backyard telescope over a period of years, and you’ll see sunspots ebb and flow in an 11 year period of activity. The dazzling ‘surface’ of the Sun where these spots are embedded is actually the photosphere, and using a small telescope tuned to hydrogen-alpha wavelengths you can pick up prominences in the warmer chromosphere above. This cycle is actually is 22 years in length (that’s 11 years times two), as the Sun flips polarity each time. A hallmark...

A saros period is just eight hours shy of 18 years and 11 days, which in turn is equal to 223 synodic, 242 anomalistic or 239 draconic months. The name saros was first described by Edmond Halley in 1691, who took it from a translation of an 11th century Byzantine dictionary. The plural of saros is saroses. This also means that solar and lunar eclipses one saros period apart share nearly the same geometry, shifted 120 degrees in longitude westward. For example, the April 4th lunar eclipse is member number 30 in a cycle of 71 lunar eclipses belonging to...

Wife and I, in hot tub this morning, just before dawn, caught sight of a long-duration, glorious meteor/fireball with a long tail. For us (in Eastern Arizona, White Mountains), it began at about 10 o'clock high in the NW sky and arced toward the western horizon. Lasted a good 15 seconds, very bright. Anyone else see it?

Explanation: As spring comes to planet Earth's northern hemisphere, familiar winter constellation Orion sets in early evening skies and budding trees frame the Hunter's stars. The yellowish hue of cool red supergiant Alpha Orionis, the great star Betelgeuse, mingles with the branches at the top of this colorful skyscape. Orion's alpha star is joined on the far right by Alpha Tauri. Also known as Aldebaran and also a giant star cooler than the Sun, it shines with a yellow light at the head of Taurus, the Bull. Contrasting blue supergiant Rigel, Beta Orionis, is Orion's other dominant star though, and...

Explanation: It quickly went from obscurity to one of the brighter stars in Sagittarius -- but it's fading. Named Nova Sagittarii 2015 No. 2, the stellar explosion is the brightest nova visible from Earth in over a year. The featured image was captured four days ago from Ranikhet in the Indian Himalayas. Several stars in western Sagittarius make an asterism known as the Teapot, and the nova, indicated by the arrow, now appears like a new emblem on the side of the pot. As of last night, Nova Sag has faded from brighter than visual magnitude 5 to the edge...

Explanation: How different does the universe look on small, medium, and large scales? The most famous short science film of its generation gives breathtaking comparisons. That film, Powers of Ten, originally created in the 1960s, has now been officially posted to YouTube and embedded above. Please click the above arrow to see the nine minute movie for yourself. From a picnic blanket near Chicago out past the Virgo Cluster of Galaxies, every ten seconds the film zooms out to show a square a factor of ten times larger on each side. The video then reverses, zooming back in a factor...

The more planetary systems astronomers discovered, the more our own solar system looked like an oddball. Exoplanets – at least the ones big enough for us to see – tended to be bigger than Earth, with tight orbits that took them much closer to their host stars. In multi-planet systems, these orbits tended to be much closer together than they are in our solar system. For instance, the star known as Kepler-11 has six planets closer to it than Venus is to the sun. Why does our solar system look so different? Astrophysicists Konstantin Batygin of Caltech and Greg Laughlin...

Explanation: Birds don't fly this high. Airplanes don't go this fast. The Statue of Liberty weighs less. No species other than human can even comprehend what is going on, nor could any human just a millennium ago. The launch of a rocket bound for space is an event that inspires awe and challenges description. Pictured above, an Atlas V rocket lifts off carrying NASA's Magnetospheric Multiscale Mission into Earth orbit 10 days ago to study the workings of the magnetosphere that surrounds and protects the Earth. From a standing start, the 300,000 kilogram rocket ship left to circle the Earth...

On July 14, NASA’s New Horizons spacecraft will fly past Pluto, offering the first close-up look at that small, distant world and its largest moon, Charon. These denizens of the outer solar system will be transformed from poorly seen hazy bodies to tangible worlds with distinct features. Now, the public can help decide what labels will go on the images and maps coming from the flyby. The SETI Institute has announced the launch of its “Our Pluto” campaign, which is soliciting input on how to name features on the surfaces of Pluto and Charon. ... The science team will not...

Explanation: Can the Sun be eclipsed twice at the same time? Last Friday was noteworthy because part of the Earth was treated to a rare total eclipse of the Sun. But also on Friday, from a part of the Earth that only saw part of the Sun eclipsed, a second object appeared simultaneously in front of the Sun: the Earth-orbiting International Space Station. Although space station eclipses are very quick -- in this case only 0.6 seconds, they are not so rare. Capturing this composite image took a lot of planning and a little luck, as the photographer had to...

Explanation: Snowy and cold is weather you might expect at the start of spring for Longyearbyen on the Arctic archipelago of Svalbard, Norway. But that turned out to be good weather for watching the Moon's umbral shadow race across northern planet Earth. The region was plunged into darkness for 3 minutes during the March 20 total solar eclipse while insulated eclipse chasers witnessed the dark Sun in the cold clear sky. In this well-timed snapshot captured near the end of totality, the Moon's shadow sweeps away from the horizon and the solar corona fades as the lunar disk just begins...

"The gas jets coming out of the comet - they are acting like thrusters and are slowing down the comet," said flight director Andrea Accomazzo. The European Space Agency official was speaking this week at the Royal Aeronautical Society in London. He was describing how his team has learnt to fly Rosetta around the 10-billion-tonne, 4km-wide body with remarkable precision. Navigators use a system of landmarks on the comet to understand how it is rotating and moving through space. This information is fed into a model that helps plan a trajectory for the satellite. And it was while running this...

Explanation: Today's date marks an Equinox and a New Moon. Remarkably, while the exact timing of both geocentric events occur within a span of only 13 hours, the moon also reaches its new phase only 14 hours after perigee, the closest point in its orbit. That makes the Equinox New Moon the largest New Moon of 2015, though hard to see since that lunar phase presents the Moon's dark, night side to planet Earth. Still, in this well composed image of a young lunar phase from late January you can glimpse both night and day on the lunar surface, the...

The nova that erupted in the Sagittarius Teapot on March 15th has continued to brighten. It's now about magnitude 4.9, in easy binocular view before dawn. Anyone see it naked-eye yet? Update Friday March 20: It's still brightening — to about magnitude 4.9 as of last night! That's a magnitude brighter than at the nova's discovery five days earlier. No telling when it will stop. And, Sagittarius is getting a little higher before dawn every day.

Pupils at a primary school were banned from watching today's once-in-a-generation eclipse because of 'religious and cultural reasons', it has emerged. Parents of children at North Primary School in Southall, London, said they were 'outraged' by the decision and claimed it showed a triumph of 'religious superstition' over scientific education. Phil Belman, whose seven-year-old daughter goes to the school, met with headteacher Ivor Johnstone who said he was unable to elaborate on the decision because of 'confidentiality'. [snip] The headteacher said: 'The school made this decision when we became aware of religious and cultural concerns associated with observing an eclipse...

LONDON, March 3 A photographer in London captured a rare photo showing a small weasel appearing to ride on a woodpecker, but he said the mammal was actually attacking the bird. Martin Le-May of Essex said he and his wife, Ann, were walking Monday in Hornchurch Country Park when they came across the unusual sight. "I heard a distressed squawking noise and feared the worst," Le-May told the BBC. "I soon realized it was a woodpecker with some kind of small mammal on its back." Le-May said the woodpecker was in a struggle for its life with the unwanted passenger,...

Sifting through the center of the Milky Way galaxy, astronomers have made the first direct observations -- using an infrared telescope aboard a modified Boeing 747 -- of cosmic building-block dust resulting from an ancient supernova.

Curious if there are any eclipse viewers out there. Reports?

<p>Starting in the early morning hours this Friday, Earthlings are in for an incredible event as three celestial events happen all at once!</p> <p>A Supermoon happens when a full or new moon occurs right when the moon is closest to the Earth (perigee) during its elliptical orbit. In other words, the moon will look ginormous on Friday, albeit very dark and faint.</p>