Latest Dark energy Stories

2010-03-01 10:45:00

Using entire galaxies as lenses to look at other galaxies, researchers have a newly precise way to measure the size and age of the universe and how rapidly it is expanding, on par with other techniques. The measurement determines a value for the Hubble constant, which indicates the size of the universe, and confirms the age of the universe as 13.75 billion years old, within 170 million years. The results also confirm the strength of dark energy, responsible for accelerating the expansion of...

2010-02-17 12:00:00

WASHINGTON, Feb 17 /PRNewswire-USNewswire/ -- New findings from NASA's Chandra X-ray Observatory have provided a major advance in understanding a type of supernova critical for studying the dark energy that astronomers think pervades the universe. The results show mergers of two dense stellar remnants are the likely cause of many of the supernovae that have been used to measure the accelerated expansion of the universe. (Logo: http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO ) These...

2010-01-05 08:19:18

University of Notre Dame astronomer Peter Garnavich and a team of collaborators have discovered a distant star that exploded when its center became so hot that matter and anti-matter particle pairs were created. The star, dubbed Y-155, began its life around 200 times the mass of the sun but probably became "pair-unstable" and triggered a runaway thermonuclear reaction that made it visible nearly halfway across the universe. Garnavich and his collaborators discovered the exploding star during...

2009-11-17 08:20:00

Astronomers find prime suspect for a Type Ia supernova Using ESO's Very Large Telescope and its ability to obtain images as sharp as if taken from space, astronomers have made the first time-lapse movie of a rather unusual shell ejected by a "vampire star", which in November 2000 underwent an outburst after gulping down part of its companion's matter. This enabled astronomers to determine the distance and intrinsic brightness of the outbursting object. It appears that this double star system...

2009-11-02 15:10:00

A detailed picture of the seeds of structures in the universe has been unveiled by an international team co-led by a Cardiff University scientist. The team has obtained extremely precise data about the early universe, using a telescope near the South Pole in the Antarctic. Their measurements of the cosmic microwave background - a faintly glowing relic of the hot, dense, young universe - provide further support for the standard cosmological model of the universe. The findings confirm the...

2009-08-12 12:42:02

The stellar explosions known as type 1a supernovae have long been used as "standard candles," their uniform brightness giving astronomers a way to measure cosmic distances and the expansion of the universe. But a new study published this week in Nature reveals sources of variability in type 1a supernovae that will have to be taken into account if astronomers are to use them for more precise measurements in the future.The discovery of dark energy, a mysterious force that is accelerating the...

2009-08-07 09:30:00

Several ways have been proposed to examine dark energy, in hopes of finding out just what it is. One of them, "supernovae" for short, certainly works: it's how dark energy was discovered in the first place. Other independent techniques, such as weak gravitational lensing and baryon acoustic oscillation, also promise great power but are as yet unproven.These three techniques all have a share of the proposed Joint Dark Energy Mission (JDEM), a satellite design managed by NASA with the...

2009-06-11 09:31:01

U.S. astronomers using radio telescopes to measure the distance to a distant galaxy have created a yardstick for calibrating large astronomical distances. The radio astronomers said their yardstick also demonstrates an important method that could help determine the nature of the so-called dark energy that pervades the universe. We measured a direct, geometric distance to the galaxy, independent of the complications and assumptions inherent in other techniques, James Braatz of the National...

2009-05-19 07:20:00

A simple new method standardizes the brightness of Type Ia supernovae Members of the international Nearby Supernova Factory (SNfactory), a collaboration among the U.S. Department of Energy's Lawrence Berkeley National Laboratory, a consortium of French laboratories, and Yale University, have found a new technique that establishes the intrinsic brightness of Type Ia supernovae more accurately than ever before. These exploding stars are the best standard candles for measuring cosmic distances,...

2009-05-13 13:23:00

Book Also Examines True Origins of Dark Matter and Dark Energies in our Universe POCKING, Germany, May 13 /PRNewswire/ -- In the new book titled 96 % Dark Universe - Lost and Found, available today from Lulu.com, scientist Dr. Henryk Frystacki is setting new directions in cosmic super-symmetry - proposing solutions for dark matter and dark energies, which account for 96% of our universe according to current models of cosmology. Previously a neglected topic, these days the quest for the...

Latest Dark energy Reference Libraries

2014-01-12 00:00:00

Image Caption: The Hubble Extreme Deep Field (XDF) was completed in September 2012 and shows the farthest galaxies ever photographed by humans. Each speck of light in the photo is an individual galaxy, some of them as old as 13.2 billion years; the observable universe is estimated to contain more than 200 billion galaxies. Credit: NASA/Wikipedia What is Cosmology? I once commented to an acquaintance that I was fascinated by the field of Cosmology, and mused that if I had more time, I...

2004-10-19 04:45:41

Quintessence (Dark Energy) -- Quintessence or dark energy is a hypothetical form of energy postulated to exist in order to explain observations of an accelerating universe. This energy would act like a vacuum pressure, pushing things apart. Other attempts to explain these recent observations involve a non-zero cosmological constant, which has the same effect. Indeed, sometimes quintessence is said to result in a non-zero cosmological constant, and conversely a non-zero cosmological...

2004-10-19 04:45:40

Wilkinson Microwave Anisotropy Probe (WMAP) -- The Wilkinson Microwave Anisotropy Probe (WMAP) was launched on June 30, 2001 at 3:46 p.m. EDT at Cape Canaveral Air Force Station, Florida, USA. The goal of WMAP was to map out minute differences in the Cosmic Microwave Background (CMB) radiation which would help test theories of the nature of the universe. On February 11, 2003, the public relations group from NASA made a press release regarding the age and composition of the universe....

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Word of the Day
  • A murmuring sound; a rushing or whistling sound, like that of the wind; a deep sigh.
  • A gentle breeze; a waft; a breath.
  • Any rumor that engages general attention.
  • A cant or whining mode of speaking, especially in preaching or praying; the chant or recitative characteristic of the old Presbyterians in Scotland.
  • To make a rushing, whistling, or sighing sound; emit a hollow murmur; murmur or sigh like the wind.
  • To breathe in or as in sleep.
  • To utter in a whining or monotonous tone.
According to the OED, from the 16th century, this word is 'almost exclusively Scots and northern dialect until adopted in general literary use in the 19th.'