A new image taken by the Subaru Telescope shows tens of thousands of previously unseen comet-shaped knots lighting up the Helix Nebula like a spectacular fireworks display frozen in time.

The Helix Nebula, NGC 7293, is located just 710 light years from Earth and was the first planetary nebula in which knots were observed. Planetary nebula represent the final stages in the lives of low-mass stars, like our Sun, as they throw off shells of gaseous material into space. Although planetary nebulae can look like explosive fireworks displays, the process takes between some 10,000 to 1,000,000 years.

An international team of astronomers used the Subaru telescope in Hawaii to study the hydrogen molecule emission of the nebula in the infrared, and discovered knots of material throughout the entire nebula. Usually these molecules are destroyed by the ultraviolet radiation in space, but in this case have been protected by the knots of gas and dust observed in optical images. The comet-like shape of these objects result from the steady evaporation of gas from the knots, produced by strong winds and ultraviolet radiation from the dying star in the heart of the nebula.

"This research shows how the central star slowly destroys the knots and highlights the places where molecular and atomic material can be found in space," says lead astronomer Mikako Matsuura, previously at the National Astronomical Observatory of Japan and now at University College London.

The infrared images show the knots extending out to greater distances than previously observed, with the extent of the 'tails' varying with the distance from the central star, mimicking the behaviour of Solar System comets which have larger tails when they are closer to the Sun and when wind and radiation is stronger.

The astronomers suggest there may be as many as 40,000 knots in the nebula, each of which are billions of kilometers across and amounting to a combined mass of 30,000 Earths. The origin of the knots – whether remnants of the star's planetary system or material ejected from the star itself – is currently unknown, but either way, will shed light on the lives of stars and planetary systems.

Our latest 132-page Astronomy Now special edition is an extravaganza of astronomy for the year ahead, with a complete 30-page guide to observing the planets, moon, meteor showers, two solar eclipses, and the deep sky in 2010.
 U.K. STORE
 E.U. STORE
 U.S. & WORLDWIDE STORE

Hubble Reborn
Hubble Reborn takes the reader on a journey through the Universe with spectacular full-colour pictures of galaxies, nebulae, planets and stars as seen through Hubble's eyes, along the way telling the dramatic story of the space telescope, including interviews with key scientists and astronauts.
 U.K. STORE
 E.U. STORE
 U.S. & WORLDWIDE STORE

3D Universe
Witness the most awesome sights of the Universe as they were meant to be seen in this 100-page extravaganza of planets, galaxies and star-scapes, all in 3D!
 U.K. STORE
 E.U. STORE
 U.S. & WORLDWIDE STORE

This special publication features the photography of British astro-imager Nik Szymanek and covers a range of photographic methods from basic to advanced. Beautiful pictures of the night sky can be obtained with a simple camera and tripod before tackling more difficult projects, such as guided astrophotography through the telescope and CCD imaging.
 U.K. STORE
 E.U. STORE
 U.S. & WORLDWIDE STORE

Explore the Universe with these new versions of the award-winning Starry Night Software. Available now from the Astronomy Now Store.
 U.K. STORE
 E.U. STORE
 U.S. & WORLDWIDE STORE

Astronomy Now is pleased to announce the publication of Exploring Mars. The very best images of Mars taken by orbiting spacecraft and NASA's Spirit and Opportunity rovers fill up the 98 glossy pages of this special edition!
 U.K. STORE
 E.U. STORE
 U.S. & WORLDWIDE STORE

This new poster features some of the best pictures from NASA's amazing Mars Exploration Rovers Spirit and Opportunity.
 U.K. STORE
 E.U. STORE
 U.S. & WORLDWIDE STORE