NATIONAL GEOGRAPHIC'S SPACE PICTURES THIS WEEK LXV

Space Pictures This Week: Starburst Aurora, Milky Way Portraits
By Andrew Fazekas, National Geographic News, 5 July 2013.

A galaxy hunter takes a last look, the Milky Way shines, and auroras shimmer in this week's best space pictures.

1. Cosmic Starburst

Photograph by Jeff Wallace, National Geographic Your Shot

A colourful starburst-shaped aurora blankets the entire sky above Morinville, Alberta (map), on the night of June 29.

"It was very strong and seemed to [be] surrounded by an umbrella of light, almost reaching the horizon. Humbling," said photographer Jeff Wallace.

Two days before a large solar storm had erupted on the surface of the sun, sending a massive cloud of charged particles into space toward Earth. Upon arrival, the coronal mass ejection slammed into our planet's magnetic field, sparking a bright display of northern lights seen across many northern countries.

The sun is currently entering peak activity levels in its 11-year cycle. Numerous sunspots form on a near-daily basis, resulting in an increase in solar storms that fling charged particles from the sun's surface and produce geomagnetic storms here on Earth. (Read about solar storms in the June 2012 issue of National Geographic magazine.)

2. Last Look

Like a cosmic pinwheel, spiral galaxy Messier 94 shines bright in ultraviolet light in one of the last snapshots taken by NASA's Galaxy Evolution Explorer (GALEX) satellite before it was shut down on June 28.

Sitting 17 million light-years from Earth in the northern constellation Canes Venatici, the galaxy's core has a distinct ring structure wrapped by a set of spidery arms made of millions of stars.

After a decade of scanning the skies for everything from ghostly nebulae to distant star factories, GALEX mapped hundreds of millions of galaxies across ten billion light-years.

"In the last few years, GALEX studied objects we never thought we'd be able to observe, from the Magellanic Clouds to bright nebulae and supernova remnants in the galactic plane," said David Schiminovich of Columbia University in New York City, in a statement.

"Some of its most beautiful and scientifically compelling images are part of this last observation cycle," said the GALEX team scientist.

3. Pouring Light

Photograph by David Mills, National Geographic Your Shot

Like a river of stars, the diffuse band of light that is the Milky Way appears to spill onto a rocky peak near Springdale, Utah (map), in an image submitted to National Geographic's Your Shot community on June 25.

4. Celestial Fireworks

Looking like a skyrocket from a fireworks show, Comet ISON is seen here in this false-colour image taken by the Hubble Space Telescope on May 8, as it heads toward an encounter with the sun later this year.

At the time this image was taken, the giant icy visitor from the outer solar system was still 408 million miles (656 million kilometres) from Earth, between the orbits of Mars and Jupiter.

The teardrop-shaped tail of this potential "comet of the century" is formed from gas and dust flung off its icy nucleus as it begins to melt from the heat of the sun.

Over the next few months as it approaches the sun, it's predicted to produce a bigger and brighter tail that may become easily visible from Earth at the end of November 2013.

5. Duelling Glows

Photograph by Jeff Dai, National Geographic Your Shot

Two ghostly glows - one from the Milky Way and one from zodiacal light - brighten the skies over Minya Konka, the highest mountain in the Sichuan Province of China.

The pyramid-shaped glow above the horizon (centre), called zodiacal light, is caused by the reflection of sunlight off a countless number of dust particles between the planets in the solar system.

[Source: National Geographic News. Edited.]