NATIONAL GEOGRAPHIC'S SPACE PICTURES THIS WEEK XLIV

Space Pictures This Week: Australia Burns, Pulsars Wobble
By National Geographic News, 11 January 2013.

The sun rages, Australia burns, and pulsars wobble in our roundup of the week's best space pictures.

1. Australia Burning

Wildfires scorch Australia in this image taken from the International Space Station and released January 8. To make matters worse, on January 7, the country experienced their hottest day on record, with average temperatures hitting 104.59 degrees Fahrenheit (40.33 degrees Celsius).

Forecasts call for even higher temperatures next week - so high in fact that Australia's Bureau of Meteorology had to add a new colour to their temperature scale. (See more pictures of Australia's wildfires.)

2. Revelations

This new Hubble Space Telescope image of a nearby star, Fomalhaut, and its surrounding disc of debris have made astronomers sit up and take notice. That's because the picture, released January 8, reveals that the debris field - made of ice, dust, and rocks - is wider than previously thought, spanning an area 14 to 20 billion miles from the star.

Scientists have also used the image to calculate the path of a planet, Fomalhaut b, as it makes its away around the star. It turns out that the planet's 2,000-year elliptical orbit takes it three times closer to Fomalhaut than previously thought, and that its eccentric path could send it ploughing through the rock and ice contained in the debris field.

The resulting collision, if it happens, could occur around the year 2032 and result in a show similar to what happened when the comet Shoemaker-Levy 9 crashed into Jupiter, astronomer Paul Kalas, of the University of California at Berkeley, said in a statement.

3. Stars Over Tufa

The Milky Way shines over Mono Lake, located east of Yosemite in California's Sierra Nevada mountain range (map), in an image released January 6. At a million years old, Mono Lake is one of the oldest lakes in North America.

The venerable water body is host to alien-looking formations called tufa, the result of limestone build-up. Teaming with brine shrimp, alkali flies, and birds, Mono Lake was also the source of a bacteria scientists suspected of replacing phosphorus - an essential ingredient in DNA - with arsenic, fuelling speculation on the possibility of life on other planets.

Although those suspicions have since been discounted, images such as this one show that Mono Lake continues to provide a window into the universe.

4. Sun's Saga

This snapshot of a solar eruption, released this week by NASA's Solar Dynamics Observatory, reveals the balletic contortions of plasma as it tracks the sun's magnetic field.

Most of the plasma fell back into the sun since there was insufficient magnetic force to propel it into space. (Related: "Solar 'Tsunami'-Giant Double Sun Eruption Caught on Video.")

5. Everglades From Space

NASA's Moderate Resolution Imaging Spectroradiometer captured this image of Florida in late December 2012. The picture, released January 7, captures the muddy-green colour of the state's Everglades region, while the mint green colour of the surrounding seawater signals the presence of phytoplankton. (Related: "Pythons Eating Through Everglades Mammals at 'Astonishing' Rate?")

6. Optics Upgrade

This crisp image of part of the Orion Nebula, released January 9, was taken by newly installed optics at the Gemini Observatory. This advanced system allows the observatory's two infrared optical telescopes - one installed in Hawaii and the other in Chile - to make observations while reducing distortions due to Earth's atmosphere. (See more nebulae pictures.)

7. Celestial Icebergs?

New data from NASA's Cassini mission suggests that ice rich in methane and ethane could be floating on a hydrocarbon sea on Saturn's moon Titan. This artist's conception, released January 8 by NASA's Jet Propulsion Laboratory, envisions otherworldly icebergs basking in a reddish glow. (Related: "Launch Boat to Saturn Moon, Scientists Propose.")

8. Ejected

Scientists are seeing the Vela pulsar - a thousand light-years from Earth - in a whole new light. Images from NASA's Chandra X-ray Observatory, released January 7, show the rapidly rotating neutron star ejecting a particle stream that looks like a rotating helix.

This suggests that Vela could be wobbling as it whips around 11 times a second. If confirmed, it would be the first example of this kind of movement in a neutron star jet.

[Source: National Geographic News. Edited.]