Astronomy Now Home
Home Magazine Sky Chart Resources Store

On Sale Now!



The September 2010 issue of Astronomy Now, the UK's best-selling astronomy magazine, is now on sale in newsagents!



Top Stories



Astronomers discover new solar system
...Using ESO's sensitive HARP instrument, astronomers have discovered a solar system containing at least five planets, with indications that two more, including a hot, rocky world, might also be present...
  READ MORE

A new way to weigh planets
...Instead of determining the mass of a planet by measuring the orbits of moons or spacecraft around them, astronomers have come up with a new method using radio signals from pulsars...
  READ MORE

Cosmic lens magnifies dark energy
...Astronomers have taken an important step forward in the quest to solve the mystery of dark energy by using galaxies to magnify the distant Universe...
  READ MORE








Small Magellanic Cloud
gives up its jewels

KEITH COOPER
ASTRONOMY NOW
Posted: 06 January 2010


Bookmark and Share

The Spitzer Space Telescope has produced this wonderfully colourful picture of the Small Magellanic Cloud (SMC) to explore how one of our nearest galactic neighbours is forming stars.

Spitzer’s new infrared image of the Small Magellanic Cloud. Image: NASA/JPL–Caltech/STScI.

Taken in infrared wavelengths, the colours on display here are not true colours, but merely representations of the infrared light. The blue regions, representing a wavelength of 3.6 microns (3.6 millionths of a metre), show older stars in the SMC; green regions at eight microns indicate dust made from organic molecules that have been recycled through previous generations of stars; and red areas at 24 microns point to places where stars are currently being born in cold molecular gas clouds.

“It’s quite the treasure trove,” says Karl Gordon, who led the imaging team from the Space Telescope Science Institute in Baltimore, USA. “Because this galaxy is so close and relatively large, we can study all the various stages and facets of how stars form in one environment.”

The SMC is 210,000 light years away and, along with its cousin the Large Magellanic Cloud (LMC), makes a splendid sight in Southern Hemisphere skies. Astronomers have recently discovered that the Magellanic Clouds don’t orbit the Milky Way, but are merely passing through our neighbourhood with an entourage of smaller dwarf galaxies in tow. According to new findings presented this week at the meeting of the American Astronomical Society in Washington, DC, 2.5 billion years ago close encounters with each other and the Milky Way triggered violent bursts of stellar creation in the Magellanic Clouds. The radiation winds from the resulting hot young stars and exploding supernovae blew out rivers of gas that has since become the Magellanic Stream

Spitzer’s 2006 image of the Large Magellanic Cloud. Image: NASA/JPL–Caltech/M Meixner (STScI)/SAGE Legacy Team.

These cycles of star formation create large quantities of dust that Spitzer, with its infrared eyes, can peer through. It is finding that the SMC is similar to galaxies in the early Universe, in that it is deficient in heavy elements that are produced inside stars. Surveys suggest that the SMC contains merely one-fifth of the abundance of elements heavier than helium that the Milky Way possesses. These heavy elements are crucial for creating planets.

The aim of the new Spitzer images is to get a better grasp of how many stars are forming in the SMC right now. “Observations in the infrared give us a view into the birthplace of stars, unveiling the dust enshrouded locations where stars have just formed,” says Gordon.

The image was taken early in 2009, before Spitzer ran out of the coolant that keeps its instruments chilled so no thermal noise interferes with the observations. Since May 2009, when the coolant ran dry, Spitzer has been on a warm mission, meaning that it can only observe in specific infrared wavelengths.

In 2006 Spitzer also imaged the LMC, revealing even more dusty stars and dust cocooned star-forming nebulae. That image is colour-coded the same as the SMC image, with the blue regions representing older stars that make up the LMC’s small, central bar.

2010 Yearbook
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

Infinity Rising
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

Starry Night
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

Exploring Mars
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

Mars rover poster
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

HOME | NEWS ARCHIVE | MAGAZINE | SOLAR SYSTEM | SKY CHART | RESOURCES | STORES | SPACEFLIGHT NOW

© 2010 Pole Star Publications Ltd.