Astronomy Now Home
Home Magazine Sky Chart Resources Store

On Sale Now!



The June 2013 issue of Astronomy Now is on sale! Order direct from our store (free 1st class post & to UK addresses). The Astronomy Now iPad/iPhone editions are now available worldwide in the iTunes 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








WMAP finishes nine-year probe of infant Universe
STEPHEN CLARK
SPACEFLIGHT NOW
Posted: 07 October 2010


Bookmark and Share

The WMAP satellite devoted to studying the genesis of the universe has finished nine years of observations, but NASA will continue funding the mission for two more years so researchers can extract every bit of science from its ground-breaking observations.


Artist's concept of WMAP in space. Credit: NASA/WMAP science team
 
Launched in June 2001, the Wilkinson Microwave Anisotropy Probe collected its last science data Aug. 20 and fired thrusters Sept. 8 to leave its operational orbit.

WMAP was stationed about 930,000 miles from Earth at the L2 point, a gravitationally stable location where the tug of Earth's gravity keeps a spacecraft in lockstep with the planet as it orbits the sun. The L2 point is located on the side of Earth opposite the sun.

The spacecraft is now in a permanent parking orbit around the sun, according to a NASA statement releaesd Wednesday.

"We launched this mission in 2001, accomplished far more than our initial science objectives, and now the time has come for a responsible conclusion to the satellite's operations," said Charles Bennett, WMAP's principal investigator at Johns Hopkins University.

The spinning WMAP satellite scanned the sky to measure tiny variations in the temperature of the cosmic microwave background radiation 380,000 years after the Big Bang. Scientists consider the CMB the first light from the young universe after matter and light could exist independently as the universe cooled.

Only sensitive microwave space telescopes can detect the temperature fluctuations, which amount to just a millionth of a degree against an average backdrop of less than -450 degrees Fahrenheit. The measurements reveal warm and cool pockets in the infant universe, the distribution of energy before galaxies and stars began forming.

Among WMAP's accomplishments are the most accurate determination of the age of the universe at 13.75 billion years old, plus or minus 1 percent.

And WMAP confirmed normal atomic matter only makes up 4.6 percent of the material in the known universe. Dark matter, which has not been detected yet, makes up another 23 percent of the universe, while exotic dark energy comprises the remaining 72 percent.

The mission's ultimate legacy is still being written.


A mosaic of the first seven years of WMAP observations showing small fluctuations in the cosmic microwave background temperature. Credit: NASA/WMAP science team
 
The science team will be on the job through 2012 analyzing the final two years of data gathered by WMAP. Only the first seven years of results have been processed so far.

"WMAP has opened a window into the earliest universe that we could scarcely imagine a generation ago," said Gary Hinshaw, the mission manager at NASA's Goddard Space Flight Center. "The team is still busy analyzing the complete nine-year set of data, which the scientific community eagerly awaits."

NASA approved the two-year post-operations phase after a panel of senior independent researchers recommended funding further processing of raw WMAP data and its public release.

"WMAP gave definitive measurements of the fundamental parameters of the universe," said Jaya Bapayee, WMAP program executive at NASA Headquarters. "Scientists will use this information for years to come in their quest to better understand the universe."

A European Space Agency mission named Planck carries instruments covering a frequency range 10 times greater than WMAP. Planck launched in 2009 finished the first of four planned sky surveys earlier this year.

Scientists say WMAP's measurements complement Planck and will continue to be useful in the future.

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

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

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.
 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

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

© 2013 Pole Star Publications Ltd.