Loving Dark Matter Rather Than Light
December 31, 2011
There are two ways to describe dark things in science. One is phenomena we know exist, even if invisible to us, because we can measure their effects with instruments (X-rays, infrared radiation). The other is darkness as a placeholder for something not yet explained. Cosmologists have been talking about “dark matter” for decades now, and “dark energy” since the 1990s. Which category of dark ideas are they? Whether scientifically valid phenomena or placeholders for ignorance, one thing is clear from recent articles: much more knowledge is needed.
Observations Upset Models of Stellar Evolution
December 22, 2011
Stellar evolution models go back decades. Ever since the Hertzsprung-Russell diagram came out in 1910 (graphing temperature against luminosity), showing most stars fell on a line called the “main sequence”, astrophysicists have sought to understand the life cycle of stars from birth to death. In general, the story goes, collapsing clouds of gas and dust produce main-sequence stars that burn nuclear fuel till they run out. Depending on their masses, they end up as supernovae, red giants or slowly-cooling cinders. While red dwarfs cool down slowly into the darkness, supernovae and red giants eject mass outward into space . Two new planets found close to a red giant are among new headaches for theorists.
Philosophy on the Phringe
December 17, 2011
Some philosophy is just common sense. Some is abstruse, recondite, and technically challenging. But when employed against common sense, such as to support the belief that everything came from nothing, philosophy can get downright weird.
Earth’s Twin: What Does “Potentially Habitable” Mean?
December 5, 2011
The Kepler spacecraft has found dozens of “potentially habitable” planets around other stars, but this week announced one that some news sources are calling “Earth’s twin.”
Selling Confabulation as Science
November 11, 2011
Science is supposed to be all about demonstrable proof through experiment. Should some scientists get away with confabulation – mere storytelling? Look at these recent headlines published on science news sites and consider whether some serious housecleaning is in order.
Space Physics and Fables
November 9, 2011
Physics is supposed to be the king of “hard science” because of its precise mathematics, predictability and falsifiability. When transferred off our planet, however, it seems speculation is the order of the day.
It’s Still a Rare Earth
September 25, 2011
Now that hundreds of extrasolar planets are known, how do they compare to ours? The Kepler spacecraft has found a varied assortment of all sizes and distances away from their parent stars. Only a few reside in their star’s habitable zones. But that’s only the first of many requirements for life. Two recent studies indicate that Earth remains a rare bird in the celestial aviary.
Trouble in Cosmologyland
September 18, 2011
Underneath the veneer of certainty portrayed by TV documentaries about the universe are deep questions and controversies. Some of these briefly appear on publicly-available news stories, only to be covered by new coats of certainty. Are the new veneers fixing the problems or, instead, whitewashing serious weaknesses in current cosmological understanding? Here are some quick looks under the veneer.
Freakish Star Stuns Astronomers
September 1, 2011
Astronomers have detected a star that should not exist. Current theory cannot explain the composition of a star in the constellation Leo. This “freakish star,” moreover, is probably not unique. What is it, exactly, that modern star formation theory does explain?
Is a Multiverse Detectable?
August 9, 2011
The idea of a multiverse (an ensemble of universes like our own visible one) has been criticized as unscientific because it would be unobservable, even in principle. Now, however, some theoretical physicists are claiming that bubble universes beyond ours could be detected in the cosmic microwave background radiation – provided they collide with our universe. Does this bring multiverse theory back into the realm of science?
Earth Uniqueness Up; SETI Down
July 29, 2011
Our earth seems special – maybe because it is. Some astronomers are seriously considering that life might be rare or unique on our rare (or unique) planet. If so, hopes for finding sentient aliens on the celestial radio dial drop accordingly. The 50th anniversary of the first SETI search came, unfortunately for search enthusiasts, came at a time when funding is harder to get.
Water, Water Everywhere in Space
July 23, 2011
The largest mass of water has been found surrounding a black hole in a quasar 12 billion light-years away. Space.com says the cloud harbors “140 trillion times more water than all of Earth’s oceans combined.” The discovery not only that “water has been prevalent in the universe for nearly its entire existence,” but that it “was present only some 1.6 billion years after the beginning of the universe.” Alberto Bolatto, of the University of Maryland, said, "This discovery pushes the detection of water one billion years closer to the Big Bang than any previous find.”
In other cosmology news:
Cosmology Could Be Way Off
June 17, 2011
The “lumpiness problem” in cosmology refuses to go away. This old conundrum about why the universe is lumpy with stars and galaxies has been around for decades. The big bang predicts no such lumps. Since the late 1990s, tiny differences in temperature measured in the cosmic background radiation held hope of being the seeds of lump formation, provided theories added copious fudge factors like dark matter, dark energy and inflation. A new survey finds more clumps than expected, casting doubt on whether the fudge factors are wrong, the hot big bang is wrong, or relativity is wrong. Words can hardly express the gravity of the situation when gravity itself – an icon of scientific verity – is called into question.
Cosmic Insanity Is Back in Vogue
June 7, 2011
There is perhaps no theory in science more weird than the “Many-Worlds” interpretation of quantum mechanics (see 07/27/2004 and 07/07/2007). One would think that Hugh Everett’s conjecture that each event splits the universe into two parallel universes with opposite outcomes would have had its 15 minutes of fame only to be laughed off the stage, […]
Spiral Galaxy Upset
May 4, 2011
In 1964, C. C. Lin and Frank Shu looked at the galaxy’s curvaceous arms and said, “You are my density.” The density-wave theory of spiral arm formation was married to galactic astronomy for nearly a half century. Now, however, we are back to the future, where theories do not always fulfill their destiny. An upstart […]