In Green Company: Aurora over Norway

Astronomy Picture of the Day

Raise your arms if you see an aurora. With those instructions, two nights went by with, well, clouds -- mostly. On the third night of returning to same peaks, though, the sky not only cleared up but lit up with a spectacular auroral display. Arms went high in the air, patience and experience paid off, and the creative featured image was captured as a composite from three separate exposures. The setting is a summit of the Austnesfjorden fjord close to the town of Svolvear on the Lofoten islands in northern Norway. The time was early 2014. Although our Sun passed the solar minimum of its 11-year cycle only a few years ago, surface activity is picking up and already triggering more spectacular auroras here on Earth.

By Max Rive

Tails Of Comet LINEAR

Astronomy Picture of the Day

Comet C/1999 S4 LINEAR is only one of many comets discovered with the Lincoln Near Earth Asteroid Research (LINEAR) telescope operating near Soccoro, New Mexico, USA. Traveling steadily southward through Earth's night sky, C/1999 S4 passed perihelion (closest approach to the Sun) yesterday on what is likely its first trip through the inner solar system. Now fading, comet LINEAR became no brighter than about 6th magnitude, but is still easily visible with binoculars in northern hemisphere skies. While the memorable comets Hale-Bopp and Hyakutake were much brighter, comet LINEAR is displaying delightful tails evident in this false-color composite image from the Crni Vrh Observatory in Slovenia. The combined series of exposures made on July 22nd are registered on the comet. In the resulting picture, stars appear as rows of dots, but the faint structures in the comet's tail are beautifully recorded. Presently seen moving from Ursa Major to Leo this comet LINEAR will begin to shine in southern hemisphere skies in August.

By Jure Skvarc, Bojan Dintinjana, Herman Mikuz (Crni Vrh Observatory, Slovenia)

Von Braun's Wheel

Astronomy Picture of the Day

Orbiting 1,075 miles above the Earth, a 250 foot wide, inflated, reinforced nylon "wheel" was conceived in the early 1950s to function as a navigational aid, meteorological station, military platform, and way station for space exploration by rocket pioneer Wernher von Braun. The wheel-shaped station could be easily rotated creating artificial gravity so that the astronauts would not suffer the effects of prolonged weightlessness. Von Braun and his team favored building a permanently occupied Earth orbiting space station from which to stage a lunar exploration program. But in the 1960s NASA adopted the Apollo Program, which called for astronauts to transfer to a landing vehicle after achieving lunar orbit, bypassing the construction of von Braun's wheel.

Sculptor Galaxy NGC 134

Astronomy Picture of the Day

NGC 134 is probably not the best known spiral galaxy in the constellation Sculptor. Still, the tantalizing island universe is a clearly a telescopic treasure in southern skies. It shares a bright core, clumpy dust lanes, and loosely wrapped spiral arms with spiky foreground stars of the Milky Way and the more diminutive galaxy NGC 131 in this sharp cosmic vista. From a distance of about 60 million light-years, NGC 134 is seen tilted nearly edge-on. It spans some 150,000 light-years, making it even larger than our own Milky Way galaxy. NGC 134's warped disk and faint extensions give the appearance of past gravitational interactions with neighboring galaxies. Like the much closer and brighter Sculptor galaxy NGC 253, tendrils of dust appear to rise from a galactic disk sprinkled with blue star clusters and pinkish star forming regions.

By CHART32 Team

An Intermediate Polar Binary System

Astronomy Picture of the Day

How can two stars create such a strange and intricate structure? Most stars are members of multiple-star systems. Some stars are members of close binary systems where material from one star swirls around the other in an accretion disk. Only a handful of stars, however, are members of an intermediate polar, a system featuring a white dwarf star with a magnetic field that significantly pushes out the inner accretion disk, only allowing material to fall down its magnetic poles. Shown above is an artist's depiction of an intermediate polar system, also known as a DQ Hercules system. The foreground white dwarf is so close to the normal star that it strips away its outer atmosphere. As the white dwarf spins, the columns of infalling gas rotate with it. The name intermediate polar derives from observations of emitted light polarized at a level intermediate to non-disk binary systems known as polars. Intermediate polars are a type of cataclysmic variable star system.

By Mark Garlick (Space-art)

In Green Company: Aurora over Norway

Astronomy Picture of the Day

Raise your arms if you see an aurora. With those instructions, two nights went by with, well, clouds -- mostly. On the third night of returning to same peaks, though, the sky not only cleared up but lit up with a spectacular auroral display. Arms went high in the air, patience and experience paid off, and the creative featured image was captured as a composite from three separate exposures. The setting is a summit of the Austnesfjorden fjord close to the town of Svolvear on the Lofoten islands in northern Norway. The time was early 2014. Although our Sun passed the solar minimum of its 11-year cycle only a few years ago, surface activity is picking up and already triggering more spectacular auroras here on Earth.

By Max Rive

Tails Of Comet LINEAR

Astronomy Picture of the Day

Comet C/1999 S4 LINEAR is only one of many comets discovered with the Lincoln Near Earth Asteroid Research (LINEAR) telescope operating near Soccoro, New Mexico, USA. Traveling steadily southward through Earth's night sky, C/1999 S4 passed perihelion (closest approach to the Sun) yesterday on what is likely its first trip through the inner solar system. Now fading, comet LINEAR became no brighter than about 6th magnitude, but is still easily visible with binoculars in northern hemisphere skies. While the memorable comets Hale-Bopp and Hyakutake were much brighter, comet LINEAR is displaying delightful tails evident in this false-color composite image from the Crni Vrh Observatory in Slovenia. The combined series of exposures made on July 22nd are registered on the comet. In the resulting picture, stars appear as rows of dots, but the faint structures in the comet's tail are beautifully recorded. Presently seen moving from Ursa Major to Leo this comet LINEAR will begin to shine in southern hemisphere skies in August.

By Jure Skvarc, Bojan Dintinjana, Herman Mikuz (Crni Vrh Observatory, Slovenia)