Astronomy Now Home
Home Magazine Resources Store

On Sale Now!



The October 2014 issue of Astronomy Now is on sale! Order direct from our store (free 1st class post & to UK addresses). Astronomy Now is the only astronomy magazine specially designed to be read on tablets and phones. Download the app from Google Play Store or the Apple App Store.



Top Stories



Earthshine used to test life detection method
...By imagining the Earth as an exoplanet, scientists observing our planet's reflected light on the Moon with ESO's Very Large Telescope have demonstrated a way to detect life on other worlds...
  READ MORE

Solid buckyballs discovered in space
...Astronomers using NASA’s Spitzer Space Telescope have detected a particular type of molecule, given the nickname “buckyball”, in a solid form for the first time...
  READ MORE

Steamy water-world gets the Hubble treatment
...Hubble Space Telescope observations of a 7 Earth-mass planet find an unusual water-rich world swathed in a thick, steamy atmosphere...
  READ MORE








Galaxy cluster smashes distance record
DR EMILY BALDWIN
ASTRONOMY NOW
Posted: October 23, 2009


Bookmark and Share

Joining forces with ground-based telescopes, NASA's Chandra and Spitzer space telescopes have uncovered the most distant galaxy cluster yet at 10.2 billion light years, beating the previous record holder by one billion light years.

JKCS041 is 190 million light years across and is located in the constellation Cetus. In this Chandra X-ray image, X-ray emission is shown in blue. Image: NASA/CXC/INAF/S.Andreon et al.

Galaxy clusters are the largest gravitationally bound objects in the Universe and the new contender, JKCS041, puts theories on how structure evolved in the early Universe to the test. Forming at the boundary of when scientists believe galaxy clusters can assemble, JKCS041's vital statistics – composition, mass and temperature – will reveal more about how the Universe evolved.

“This object is close to the distance limit expected for a galaxy cluster,” says Stefano Andreon of the National Institute for Astrophysics (INAF) in Italy. “We don’t think gravity can work fast enough to make galaxy clusters much earlier.”

JKCS041 was first identified in 2006 by the United Kingdom Infrared Telescope (UKIRT), revealing component galaxies dominated by old red stars. It's record-breaking distance was determined from optical and infrared measurements by the UKIRT, the Canada-France-Hawaii Telescope in Hawaii, and NASA’s Spitzer Space Telescope. Chandra added the final piece of evidence – hot gas detected between the galaxies – proving that JKCS041 is indeed a true cluster, and not one that is still forming.

In this optical image from the Very Large Telescope, which also includes optical and infrared data from the Digitized Sky Survey, individual galaxies are seen in white. Image: DSS; ESO/VLT.

The observations also ruled out the possibility of the galaxies distributed along the same line of sight, and the extent and shape of the X-ray emission, combined with the lack of a central radio source, argue against the possibility that the X-ray emission is caused by scattering of cosmic microwave background light by particles emitting radio waves.

“This discovery is exciting because it is like finding a Tyrannosaurus Rex fossil that is much older than any other known,” says Ben Maughan from the UK's University of Bristol. “One fossil might just fit in with our understanding of dinosaurs, but if you found many more, you would have to start rethinking how dinosaurs evolved. The same is true for galaxy clusters and our understanding of cosmology.”

The hunt is now on for similar distant clusters. Previous record holder XMMXCS J2215.9-1738 was discovered by ESA's XMM-Newton space telescope in 2006 at 9.2 billion light years, but astronomers need more case studies to thoroughly test cosmological models, such as the nature and prevalence of dark matter and the destiny of our Universe.

The results of the research will appear in a forthcoming edition of the journal Astronomy & Astrophysics.

The Planets
From tiny Mercury to distant Neptune and Pluto, The Planets profiles each of the Solar System's members in depth, featuring the latest imagery from space missions. The tallest mountains, the deepest canyons, the strongest winds, raging atmospheric storms, terrain studded with craters and vast worlds of ice are just some of the sights you'll see on this 100-page tour of the planets.
 GET YOUR COPY

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.
 GET YOUR COPY

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!
 GET YOUR COPY


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

© 2014 Pole Star Publications Ltd.