NATIONAL GEOGRAPHIC'S BEST SPACE PICTURES THIS WEEK LXII

Week's Best Space Pictures: Champagne Flows, Pockmarked Moon
By Jane J. Lee, National Geographic News, 29 May 2015.

Bubbles of hot gas burst and Saturn's moon Rhea displays its cracks and crags in this week's most amazing views from space.

1. A Massive Nasty

A Wolf-Rayet star evolves quickly and is much more massive than our sun. This particular one, named Nasty 1, swirls in the middle of a two-trillion-mile-wide nebula in this illustration released by NASA.

2. A Bit of Bubbly

Young stars in nebula RCW 34 inject massive amounts of heat into pockets of gas, which start to expand. The enormous bubbles travel to the nebula's edge, where they burst into the vacuum of space. This movement is called champagne flow.

3. Mountain High

Astronauts on the International Space Station captured this image of Central Asia's Tien Shan mountain range as they flew over it. Deep blue Lake Issyk Kul (left) is the second largest mountain lake in the world after South America's Lake Titicaca.

4. Surprise Flare

Astronomers at the Alma Observatory in Chile spied an enormous flare (illustrated here) emanating from the surface of one of a pair of red giant stars named Mira. The star is near the end of its life, and activity like this flare came as a surprise.

5. Mars Probe

Engineers put a solar array through its paces in preparation for a March 2016 launch. The array is part of NASA's InSight lander, which will study Mars's deep interior in an effort to understand the early history of rocky planets.

6. Technicolor Crater

An impact crater on Mars sparkles in this enhanced colour image of sedimentary rock layers. Researchers think the site might once have hosted a lake billions of years ago, and the area was considered as a landing spot for the Curiosity rover.

7. Pockmarks

Impact craters on Saturn's moon Rhea stand out in stark relief in this image captured by the Cassini spacecraft. Rhea is the ringed planet's second largest moon after Titan.

8. A Crowd

This Hubble Space Telescope image shows the Arches Cluster, the most crowded part of the Milky Way. Located 25,000 light-years away from Earth, Arches is our galaxy’s densest known star cluster and hosts 150 of the brightest stars in the Milky Way.

Photo gallery by Emily Jan.

[Source: National Geographic News. Edited. Some links added.]