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Rings And Loops In The Stars: Planck’s Stunning New Images
Credit: M. Peel / JCBA / Planck / ESA
A ring of dust 200 light years across and a loop covering a third of the sky: two of the results in a new map from the Planck satellite. Dr Mike Peel and Dr Paddy Leahy of the Jodrell Bank Centre for Astrophysics (JCBA) presented the images today at the National Astronomy Meeting (NAM 2015) at Venue Cymru, Llandudno, Wales.
The European Space Agency (ESA) Planck satellite, launched in 2009 to study the ancient light of the Big Bang, has also given us maps of our own Galaxy, the Milky Way, in microwaves (radiation at cm- to mm-wavelengths). Microwaves are generated by electrons spiralling in the Galaxy’s magnetic field at nearly the speed of light (the synchrotron process); by collisions in interstellar plasma, by thermal vibration of interstellar dust grains, and by “anomalous” microwave emission (AME), which may be from spinning dust grains.
The relative strength of these processes changes with wavelength, and are separated using multi-wavelength measurements from Planck, from NASA’s WMAP satellite, and from ground-based radio telescopes, giving maps of each component.
WMAP Team Releases Final Results, Based On Nine Years Of Observations
Since its launch in 2001, the Wilkinson Microwave Anisotropy Probe (WMAP) space mission has revolutionized our view of the universe, establishing a cosmological model that explains a widely diverse collection of astronomical observations. Led by Johns Hopkins astrophysicist Charles L. Bennett, the WMAP science team has determined, to a high degree of accuracy and precision, not only the age of the universe, but also the density of atoms; the density of all other non-atomic matter; the epoch when the first stars started to shine; the “lumpiness” of the universe, and how that “lumpiness” depends on scale size.
In short, when used alone (with no other measurements), WMAP observations have made our knowledge of those six parameters above about 68,000 times more precise, thereby converting cosmology from a field of often wild speculation to a precision science.
Now, two years after the probe “retired,” Bennett and the WMAP science team are releasing its final results, based on a full nine years of observations.
“It is almost miraculous, says Bennett, Alumni Centennial Professor of Physics and Astronomy and Johns Hopkins Gilman Scholar at the Johns Hopkins University’s Krieger School of Arts and Sciences. “The universe encoded its autobiography in the microwave patterns we observe across the whole sky. When we decoded it, the universe revealed its history and contents. It is stunning to see everything fall into place.”
Full Story, Results and Links: http://releases.jhu.edu/2012/12/21/wmap-team-releases-final-results-based-on-nine-years-of-observations/
Johns Hopkins Astrophysicist Charles Bennett And WMAP Team Win 2012 Gruber Prize
Johns Hopkins University professor Charles L. Bennett and members of the Wilkinson Microwave Anisotropy Probe (WMAP) space mission that he led will receive the Gruber Foundation’s 2012 Cosmology Prize in Beijing, China tomorrow.
Bennett and the 26-member WMAP team will share the $500,000 prize and are being recognized by the foundation for their transformative study of an ancient light dating back to the infant universe. So precise and accurate are the WMAP results that they form the foundation of the Standard Cosmological Model.
Bennett will receive a gold medal at the International Astronomical Union meeting on August 21, and will deliver a lecture on the 22nd. Watch Bennett explain WMAP’s groundbreaking science in a video here: http://www.youtube.com/watch?v=72Y0mvXsHS0
“It is tremendously exciting to be recognized with the Gruber Cosmology Prize,” said Bennett, Alumni Centennial Professor of Physics and Astronomy and Gilman Scholar in the Henry A. Rowland Department of Physics and Astronomy at Johns Hopkins’ Krieger School of Arts and Sciences. “I have been very fortunate to work with the talented and fine people of the WMAP team, and I am particularly delighted that our entire science team has been honored with this prestigious award.”
Under Bennett’s direction, the WMAP mission determined with unprecedented precision the age, shape (WMAP nailed down the curvature of space to within 0.6% of conventional Euclidean geometry), composition and history of the universe from the first-ever, exquisitely detailed full-sky “baby picture” of the universe, dating from when it was only 378,000 years old — 13.75 billion years ago. Using this picture, the team determined that the universe consists of 72.8 percent dark energy, 22.7 percent dark matter and 4.6 percent atoms. The team also concluded that the first stars formed when the universe was only about 400 million years old. The WMAP data substantiated key predictions of the cosmic inflation paradigm that describes the first trillionth of a trillionth of a second of the universe, while at the same time ruling out some specific implementations of the theory. WMAP data also place limits on the mass of the neutrino (an elementary particle with no electrical charge and travels at almost the speed of light), and provide evidence for primordial helium, consistent with big bang theory predictions.
Rapid Expansion or Something Weird in the Early Universe
The widely-accepted theory of cosmic inflation states that our universe expanded rapidly in the moments after its birth, resulting in the immense expanse we see today.
Cosmic inflation explains why the universe is billions of years old, as well as why the universe is nearly flat. The theory’s conclusions about how the universe should look match observations by NASA’s Wilkinson Microwave Anisotropy Probe (WMAP).
But is inflation the only model that can explain the beginnings of the universe?
That’s the question that University at Buffalo physicists Ghazal Geshnizjani, Will Kinney and Azadeh Moradinezhad Dizgah set out to answer with their study, “General Conditions for Scale-Invariant Perturbations in an Expanding Universe.”
Full Story: http://www.buffalo.edu/news/13219
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