NATIONAL GEOGRAPHIC'S BEST SPACE PICTURES THIS WEEK CX

Week's Best Space Pictures: See a Supernova's Glowing Ghost
By Michael Greshko, National Geographic News, 20 May 2016.

This week, Hubble spots Mars from 50 million miles away, satellites capture a massive wildfire in Canada, and Jupiter's icy moon Europa shows off its enigmatic surface.

1. Space Ghost

First spotted in late 1572, the star explosion known as Tycho's Nova left behind gases glowing with X-rays and radio waves. Observations since 2000 have allowed scientists to make a movie of the supernova's expanding remains.

2. Bright Bees

This Hubble image shows star clusters swarming like bees around the edge-on lenticular galaxy NGC 5308, located just under 100 million light-years away in the constellation Ursa Major.

3. What Lies Beneath

This enhanced-colour view from NASA's Galileo spacecraft shows linear fractures on the icy surface of Jupiter's moon Europa. It's thought that the planet's gravity flexes Europa's icy shell, which covers a subsurface ocean.

4. So Close, Yet So Far

This Hubble image taken on May 12, 2016, shows Mars at a mere 50 million miles (80 million kilometres) away. Aerospace company Lockheed Martin just announced a concept for building a Mars space station.

5. In Harm's Way

On May 14, 2016, an International Space Station astronaut captured this view of smoke billowing from wildfires near Fort McMurray in Alberta, Canada. The fires have forced thousands of people to evacuate.

6. Getting Kinky

Saturn's F ring is filled with kinks, jets, strands, and gores caused by the gravitational tugs of two neighbouring moons, Prometheus (seen here) and Pandora. Prometheus even occasionally enters the ring.

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