Privileged Planet Website Opens

A website featuring a new book by Guillermo Gonzalez and Jay Richards, The Privileged Planet, has opened.  The subtitle of the book is How Our Place in the Cosmos Is Designed for Discovery.  The authors take issue with pessimistic views, such as those of Steven Weinberg and Carl Sagan, that our planet is “pointless” or […]

Mercury’s Magnetic Field: Another Attempt to Save Theory from Data

Nature Feb. 121 restates a puzzle about Mercury known since the Mariner 10 encounters (1974-5): …why, against expectations, does Mercury have a global magnetic field? The planet’s diminutive size means that it should have cooled quickly after it formed.  Any molten core would have become solid, or almost completely so.  A magnetic-field-generating dynamo in an […]

Comets as Cosmic Storks

Chandra Wickramasinghe and colleagues at Cardiff University have raised the bar on tale-telling ability.  They believe that comets splatting on earth can carry away germs of life that gradually spread farther and farther out, eventually escaping the sun’s pull.  Over time, they might spread life to other worlds.  They estimate that since the origin of […]

Accretion: The Missing Link in Planetary Evolution

Every school child has seen artwork of planets evolving from a disk of dust and gas around a star like our sun, but there’s a missing link in the story. How did the dust particles stick together?

Mars Rover Lands

From the scene of news at Jet Propulsion Laboratory At 8:35 p.m. Pacific Time Saturday, January 3, signal was lost as a large set of air bags bounced on the surface of Mars.  After several nail-biting minutes, signal was reacquired by two Earth stations, indicating that the Mars Exploration Rover “Spirit” had survived the heat […]

Stardust Mission Successfully Flies Through Comet Cloud

In the first of what is hoped will be a series of spectacular space missions in 2004, the Jet Propulsion Laboratory flew the Stardust spacecraft today on a wild ride right into the dusty coma of comet Wild-2 (pronounced Vilt-2).  Though the dust storm would have killed an astronaut at that range, the craft emerged […]

Keeping Planetary Rings Going for Eons

It’s common knowledge that planetary rings, like those at Saturn, don’t last forever (see 02/12/2002 headline), so scientists either have to find a way to keep them going, or admit that we live in a special period in the lifetime of the solar system to see them now.  That latter option is “philosophically unappealing” to […]

Vega Has a Neptune?

The BBC News and EurekAlert are pretty excited about a discovery at Vega, the sapphire-blue star that hangs overhead in summertime (from the Northern Hemisphere; Aussies see it at the horizon).  Astronomers think they see a clump of material that might be at the distance from the star similar to Neptune’s distance from the sun.  […]

Ring Around the Moons

51; Saturn is known for its rings, and some small moons have been found inside its rings.  But wouldn’t it be strange if some of its moons had rings of their own?  Such a thing had not been widely considered before 2007, when there was a tentative detection of a ring around Rhea (see 03/10/2008).  […]

Planets and Moons Suddenly Got Much Younger

A planet or moon covered with craters just looks old, doesn’t it?  Planetary geologists have long relied on crater counts to estimate the absolute ages of surfaces, such as on the moon, Mars, Europa, and every other solid body.  Lots of craters meant old.  Few craters meant young.  Presumably, impacting bodies came in like clockwork […]

Questioning Earth’s Privileges

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 […]

A “Completely Different Slant” on Solar System Formation

51; “Did great balls of fire form the planets?” New Scientist asks.  A new theory “challenges the notion that the solar system started out as a placid sea of dust motes which simply clumped together to form planets.” If accepted, it “puts a completely different slant on what happened in the early solar system in […]

Hiding Comets Out of Bounds

51; There’s a new theory floating around about where most of the comets came from: other stars.  For many years, astronomers hid them in an unobservable region called the Oort cloud that was assumed to be partly a remnant of the sun’s primordial disk, and material that was ejected outward.  Now, according to the BBC […]
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