NATIONAL GEOGRAPHIC'S SPACE PICTURES THIS WEEK LXXXVII

Best New Space Pictures: Saturn's Crown and Astronauts' Renown
By Dan Vergano, National Geographic News, 27 December 2013.

Winter's blue bands bound Saturn, while astronauts worked above a gleaming Earth in the week's best space pictures.

1. Astronauts Repair Space Station

Astronauts spent the holiday week working outside, replacing a busted cooling pump on the International Space Station. High above the Atlantic Ocean, NASA's Rick Mastracchio here participates in the first stage of the repairs on a 5-hour, 28-minute spacewalk. (See also: "Top 5 Space Station Repair Spacewalk Dangers.")

Mastracchio and another NASA astronaut, Mike Hopkins, successfully completed the repairs on Christmas Eve. Drama had accompanied these spacewalks after a helmet had filled dangerously with water during a previous spacewalk.

Mastracchio and Hopkins performed their repairs so efficiently, however, that a third spacewalk was cancelled because it was not needed to finish the job.

2. Landsat Reveals Gulf Stream's Glow

Abstract art has nothing on the Atlantic's Gulf Stream, seen here glowing in warm orange and cool pink in this infrared close-up taken some 300 miles (500 kilometres) off the coast of Charleston, South Carolina.

The Landsat 8 satellite shot this image of the current as it flowed north, with pockets of warmer and cooler waters revealed by the infrared imagery.

3. Spiral Galaxy Glitters

One of eight sister galaxies, NGGC 2997 hangs edge-on in the sky in this Hubble Space Telescope view. A spiral galaxy like our own Milky Way, its starry arms spin like a plate, obscured from sight by our sideways view.

NGGC resides some 25 million light-years away. Astronomers study these cosmic neighbours for clues to the structure of our own galaxy.

4. Saturn's Hexagon Crown

The real Lord of the Rings - Saturn - wears a six-sided crown, seen in this stunning image from the Cassini spacecraft. Just above the horizon, the planet's storied rings seem to drape the planet like a cloak.

The curious hexagon-shaped jet stream spinning atop the northern polar cap of Saturn has fascinated planetary scientists since its discovery in 2007.

5. Rhea Eclipses Titan

Saturn's largest moon, Titan, comes by its name honestly. Here, Rhea, the second-largest satellite of the Saturnian system, looks likely to be swallowed by Titan in this view of an eclipse from the Cassini spacecraft.

Cassini first went into orbit around Saturn in 2004, and has been delivering stunning views of Saturn and its moons ever since. The mission is scheduled to continue until 2017, funding from the space agency permitting.

6. Saturn's Winter Bands

Winter returns to Saturn's southern hemisphere, seen in this natural-colour view from the Cassini spacecraft. The bands are a sign of winter's return there. (See also: "Saturn: The Ringed Planet.")

Cassini captured this view of Saturn from a distance of 1.003 million miles (1.615 million kilometres) away. The sixth planet from the sun takes more than 29 years to complete one orbit, so Cassini scientists have had to wait a while to catch the change in seasons.

[Source: National Geographic News. Edited.]