NGC 2440: Cocoon of a New White Dwarf
21.02.2010

Like a butterfly, a white dwarf star begins its life by casting off a cocoon that enclosed its former self. In this analogy, however, the Sun would be a caterpillar and the ejected shell of gas would become the prettiest of all!

Spokes in the Helix Nebula
4.09.2008

At first glance, the Helix Nebula (aka NGC 7293), looks simple and round. But this well-studied example of a planetary nebula, produced near the end of the life of a sun-like star, is now understood to have a surprisingly complex geometry. Its extended loops and comet-shaped features have been explored in Hubble Space Telescope images.

Henize 3 401: An Elongated Planetary Nebula
31.07.2002

How do dying stars eject their outer layers? Stars that create elegant planetary nebulas like Henize 3-401, pictured above, are not unusual, causing speculation that, one day, our own Sun may look like this.

Rungs of the Red Rectangle
13.05.2004

A distinctive X-shape and ladder-like rungs appear in this Hubble Space Telescope image of the intriguing Red Rectangle Nebula. The dusty cosmic cloud was originally identified as a strong source of infrared radiation and is now believed to contain icy dust grains and hydrocarbon molecules formed in the cool outflow from an aging central star.

M27: Not A Comet
23.10.1999

While searching the skies above 18th century France for comets, astronomer Charles Messier diligently recorded this object as number 27 on his list of things which are definitely not comets. So what is it?

NGC 2346: A Butterfly Shaped Planetary Nebula
12.10.1999

It may look like a butterfly, but it's bigger than our Solar System. NGC 2346 is a planetary nebula made of gas and dust that has evolved into a familiar shape. At the heart of the bipolar planetary nebula is a pair of close stars orbiting each other once every sixteen days.

Spherical Planetary Nebula Abell 39
23.01.2001

One of the largest spheres in our Galaxy is giving valuable clues about the chemical composition of stars by its very shape. Planetary nebula Abell 39, now six light-years across, was once a sun-like star's outer atmosphere expelled thousands of years ago.

IC 4406: A Seemingly Square Nebula
16.04.2000

How can a round star make a square nebula? This conundrum came to light with the discovery of planetary nebulae like IC 4406. IC 4406 is most probably cylindrical, with its square appearance the result of our vantage point in viewing the cylinder.

IC 4406: A Seemingly Square Nebula
27.04.1998

How can a round star make a square nebula? This conundrum came to light with the discovery of planetary nebulae like IC 4406. IC 4406 is most probably cylindrical, with its square appearance the result of our vantage point in viewing the cylinder.

IC 4406: A Seemingly Square Nebula
18.06.2002

How can a round star make a square nebula? This conundrum comes to light when studying planetary nebulae like IC 4406. Evidence indicates that IC 4406 is likely a hollow cylinder, with its square appearance the result of our vantage point in viewing the cylinder from the side.