Archive for the ‘Dark Matter/Energy’ Category

Is the universe expanding asymmetrically?

Monday, 26 September 2011
by Estelle Asmodelle
Is the universe expanding asymmetrically? This image shows the two hemispheres of a spherical mapping of the cosmic microwave background. New research examining the velocities of Type Ia supernovae suggests faster expansion in the northern hemisphere of the universe, challenging the cosmological principle that the universe is expanding uniformly in all directions.

Credit: WMAP/NASA

GOSFORD: Recent examination of supernovae velocities suggests the universe may be expanding non-uniformly in its acceleration, which implies the laws of physics may vary throughout the cosmos.

Physicists working with the Supernova Cosmology Project’s Union2 data set have suggested that the expansion of the universe seems to display a preferred axis, meaning that the universe is expanding faster in one direction than any other.

See here for the full article.

Dark matter signals detected?

Thursday, 15 September 2011
by Estelle Asmodelle

CRESST Detector

This image shows the CRESST experiment. The detectors are supercooled to a temperature only slightly above absolute zero.

Credit: Credit: CRESST & The Max-Planck-Institut für Physik.

GOSFORD: Physicists have detected signals that could be interpreted as dark matter, the elusive substance believed to comprise 80% of matter in the Universe, and say it could have a lower mass than suspected.

Researchers working on the Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) experiment in Italy, have announced they have detected weakly interacting particles that may be evidence for the elusive substance, only known because of the gravitational pull it exerts on ‘normal’ (baryonic) matter.

Read the full article here:

News items for April-May

NEW METHOD OF MAPPING THE UNIVERSE USING QUASARS -BOSS.

Measuring the distant universe in 3-D

The biggest 3-D map of the distant universe ever made, using light from 14,000 quasars – supermassive black holes at the centers of galaxies billions of light years away – has been constructed by scientists with the third Sloan Digital Sky Survey (SDSS-III).

See the Phyorg article here: http://www.physorg.com/news/2011-05-distant-universe-d-boss-job.html

Or sciencecodex here: http://www.sciencecodex.com/measuring_the_distant_universe_in_3d

THE HUNTING OF DARK MATTER

The race to detect dark matter has yielded mostly confusion. But the larger, more sensitive detectors being built could change that picture soon.

If you did yet get this PDF now is a good time to download it

Article on Nature website: http://www.nature.com/news/2011/110323/pdf/471433a.pdf

THE NEW MOST MASSIVE OBJECT – CURRENT TITLE HOLDER ANYWAY:


The Most Massive Distant Object Known

 

The most massive known object in the young universe, a galaxy cluster dubbed SPT-CLJ2106-5844, is also a probe of conditions in the young universe. This image combines optical and infrared images with intensity contours from the Chandra X-ray Observatory.

Phyorg article here: http://www.physorg.com/news/2011-04-massive-distant.html

SUPER LUMINIOUS SUPERNOVA

Keck telescope images super-Luminous supernova

Images of SN 2008am obtained with the Keck I telescope’s Low Resolution Imaging Spectrometer (LRIS).Credit: D. Perley & J. Bloom / W.M. Keck Observatory

The Keck I Telescope has played a key role in unraveling the mysteries of one of the brightest supernovas ever discovered.

http://www.physorg.com/news/2011-04-keck-telescope-images-super-luminous-supernova.html

DOES DARK MATTER LINK GAMMA RAYS TO GALACTIC HAZE?

Fermi's view of the Milky Way and beyond

Fermi’s view of the Milky Way and beyond

Annihilating dark matter at the heart of the Milky Way could account for signals detected by two space telescopes, according to a pair of US physicists.

IOP website: http://physicsworld.com/cws/article/news/45804

ANITMATTER DETECTOR READY

A heavyweight, and controversial, cosmic-ray detector is set to head for the International Space Station.

The Alpha Magnetic Spectrometer will seek antimatter in deep space, and measure cosmic rays closer to home

Nature website: http://www.nature.com/news/2011/110428/full/news.2011.260.html

THE MAGNETIC UNIVERSE

We live in a magnetic universe, but much about magnetism at cosmic scales remains unknown.

universe

The magnetic field at the Milky Way’s core is at least 10 times stronger than that of the rest of the galaxy.

Cosmos: http://www.cosmosmagazine.com/node/4248/full

Another universe tugging on ours? Maybe not, researchers say

universe

A new study from the University at Buffalo contradicts the dark flow theory, showing that exploding stars in different parts of the universe do not appear to be moving in sync. Working with data on 557 such stars, called supernovae, UB scientists deduced that while the supernovae closest to Earth all shared a common motion in one direction, supernovae further out were heading somewhere else. An article announcing the research results will appear in a forthcoming edition of the peer-reviewed Journal of Cosmology and Astroparticle Physics.

Phyorg: http://www.physorg.com/news/2011-04-universe.html

Astronomers mull merger of missions

Cosmic-origins scientists convene with exoplanet hunters.

Exoplanet hunters want something to replace the postponed Terrestrial Planet Finder.

NASA’s constrained budget is encouraging some creative pairings. This week, scientists eager to find other habitable worlds explored the possibility that a future space telescope for probing the origins of stars and galaxies could serve their needs as well.

Nature: http://www.nature.com/news/2011/110427/full/472402a.html

Xenon100: ‘We hope to detect the largest proportion of the matter in space’


'We hope to detect the largest proportion of the matter in space'

 

 

The underground laboratory at Gran Sasso in Italy is the home of the Xenon100 experiment, which is being conducted as an international collaboration that includes the Heidelberg-based Max Planck Institute for Nuclear Physics to detect the mysterious particles directly. The researchers recently published the evaluations of one hundred days of measurement time. The result: although there is no significant signal for dark matter as yet, the world’s best limits for the masses and interaction strengths of the WIMPs have been obtained, and already noticeably reach into the predicted range.

Phyorg: http://www.physorg.com/news/2011-04-xenon100-largest-proportion-space.html

Scientists suggest spacetime has no time dimension

clock

The concept of time as a way to measure the duration of events is not only deeply intuitive, it also plays an important role in our mathematical descriptions of physical systems. For instance, we define an object’s speed as its displacement per a given time. But some researchers theorize that this Newtonian idea of time as an absolute quantity that flows on its own, along with the idea that time is the fourth dimension of spacetime, are incorrect. They propose to replace these concepts of time with a view that corresponds more accurately to the physical world: time as a measure of the numerical order of change.

http://www.physorg.com/news/2011-04-scientists-spacetime-dimension.html

CIB taken by the Herschel Space Observatory

This week on JPL/Nasa, there is a pretty interesting article on THE COSMIC INFRARED BACKGROUND CIB with photos taken by the Herschel Space Observatory- this intrgiues me very much, as it is the infrared version of CMB – and well worth a read.

Herschel Measures Dark Matter for Star-Forming Galaxies

A region of the sky called the

A region of the sky called the “Lockman Hole,” located in the constellation of Ursa Major, is one of the areas surveyed in infrared light by the Herschel Space Observatory. All of the little dots in this picture are distant galaxies. Image credit: ESA/Herschel/SPIRE/HerMES

http://www.jpl.nasa.gov/news/news.cfm?release=2011-057&cid=release_2011-057&msource=h20110216&tr=y&auid=7790308