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The Most Distant Object in the Universe

By David Reneke

News from the space and astronomy communities around the world.

David Reneke is an astronomy lecturer and teacher, a feature writer for major Australian newspapers and magazines, and a science correspondent for ABC and commercial radio. Subscribe to David’s free Astro-Space newsletter at www.davidreneke.com

The full text of this article can be purchased from Informit.

By combining the power of the Hubble Space Telescope, NASA’s Spitzer Space Telescope and one of nature’s zoom lenses, astronomers have found what is probably the most distant galaxy yet seen in the universe. This object offers a view of when the universe was only 3% of its present age of 13.7 billion years.

We actually see the newly discovered galaxy, named MACS0647-JD, as it was 420 million years after the Big Bang. Its light has travelled for 13.3 billion years to reach Earth, which corresponds to a massive redshift of approximately 11.

Redshift is a direct consequence of the expansion of space over cosmic time, stretching the wavelength of light and thus making a distant object appear redder than it really is. Objects with a higher redshift have had their light stretched more, and are therefore more distant from us.

The find is the latest discovery from the Cluster Lensing And Supernova Survey with Hubble (CLASH), which uses massive galaxy clusters as cosmic telescopes to magnify distant galaxies behind them. Astronomers call the effect gravitational lensing.

“This has outstripped even my expectations of what would be possible with the CLASH program,” said Rychard Bouwens, co-author of the study. “The science output in this regard has been incredible.”

About eight billion years into its journey, the galaxy’s light took a detour along...

The full text of this article can be purchased from Informit.