Are Dark Matter and Dark Energy the New Epicycles?
February 10, 2004
An article in The Economist suggests that dark matter and dark energy may not be necessary to understand the structure of the universe. It refers to two recent papers that explain the cosmic background radiation and galaxy clusters with ordinary matter, without a need for either of the other two unknown quantities. Are dark matter […]
Should Cosmologists Get Worried Yet?
January 23, 2004
The unexpected finding of mature galaxies in the early universe (see 01/02/2004) has Robert Irion worried, but he seems surprised the theorists are not. Reporting on last week’s meeting of the American Astronomical Society in the Jan. 23 issue of Science,1 he titles his article, “Early Galaxies Baffle Observers, But Theorists Shrug.” He begins: “It’s […]
January 2, 2004
The Hubble Space Telescope, with its Advanced Camera for Surveys, has taken a peek at the most distant galaxy clusters ever seen. The astronomers found “embryonic” galaxies in a “proto-cluster” of galaxies, named TN J1338-1942, that they estimate formed a mere 1.5 billion years after the Big Bang. This find has been reported in the […]
Globular Cluster Origins: Where Do We Go From Here?
January 1, 2004
The simple explanation of globular clusters as bundles of ancient stars seems to be in a state of crisis, though the authors of a paper in the Jan. 1 issue of Nature1 try to keep a stiff upper lip. They begin, “Nearly a century after the true nature of galaxies as distant ‘island universes’ was […]
Dark Energy Doubted
December 17, 2003
We’ve been told recently that two thirds of the universe consists of a mysterious phenomenon called dark energy. Now, some scientists at ESA say it doesn’t exist. Observations by the European Space Agency’s XMM-Newton X-ray Observatory of clusters of galaxies 10 billion light years distant show remarkable differences from nearby clusters in the […]
Questioning Earths Privileges
September 20, 2002
51; Two articles this week downplayed considerations that would make the Earth seem like a special place in the universe. Both have ties to NASA. Are life-friendly stars limited to a narrow band in the galaxy called the Galactic Habitable Zone (GHZ)? NASA-supported Astrobiology Magazine cast doubt on the idea. Citing a study […]
How Precise Is Precision Cosmology?
September 20, 2002
When data from the Wilkinson Microwave Anisotropy Probe (WMAP) came in, cosmologists heralded it as the era of “precision cosmology” and immediately began to make claims that resulting data map confirmed some cosmological theories and falsified others (see 02/14/2003 headline). Two papers in the Astrophysical Journal, however, are discounting the precision of the data and […]
Dark Energy Is Embarrassing
July 20, 2002
Robert Scherrer is trying to come up with a theory that combines dark matter and dark energy, reports Space.Com. “It is somewhat embarrassing to have two different unknown sources for the dominant forms of matter and energy in the universe. On the other hand, that may just be the way things are. We don’t get […]
Inflation: Cosmic, Comic, or Cosmetic?
March 20, 2002
The science media seem beside themselves with enthusiasm over some dots and lines. When scientists analyzing data from the Wilkinson Microwave Anisotropy Probe (WMAP) told reporters they determined the polarization of certain points in the cosmic microwave background, one could almost hear the yawns. But when they suggested that this tells us something about what […]
Is Dark Matter Going Out of Style?
January 20, 2002
Dark matter has been a staple in cosmological theories for decades. One of the initial reasons was that galaxy rotation curves could not be explained without it. Another was that galaxy clusters, to be held together over long ages, needed more “stuff” to bind them. Finally, Big Bang cosmologists invoke copious amounts of dark matter […]
Reality or Hubris in Scientific Claims?
January 20, 2002
51; The amount of trust the public puts in scientific claims stems partly from their incomprehensibility. The claims presented in scientific papers are often so dense and abstruse as to be unapproachable by all but specialists. Undoubtedly many people trust scientists because of their specialized education, their knowledge of mathematics, their special equipment, and their […]