Huygens Heads for Titan

At about 7:25 p.m. JPL time Christmas Eve, anxious scientists and engineers watching their monitors received bits from 800 million miles away, indicating that the Cassini spacecraft had successfully released the Huygens Probe over an hour earlier, with no faults or problems, right on schedule.  In mission control, engineers with Santa hats could be seen […]

Cassini Passes Titan a Third Time

Raw images from Cassini’s Titan-b flyover from 750 miles (see animation) have been uploaded to the website: Cassini Raw Images (proceed from this link).  Improved, processed images are now being posted at, such as this high resolution of dark terrain.  Look also at JPL the and Cassini Imaging Team websites.  In addition, teams monitoring […]

Planet-Building a Mess, or Theories a Mess?

A news release from the Spitzer Space Telescope operated by JPL says, “Astronomers Discover Planet Building is Big Mess.”  Data from the orbiting infrared observatory indicates that dust disks around stars appear to be dominated by collisions of large bodies.  Surprisingly, the dust disks do not correlate with the stars’ ages.  A study of 266 […]

Dating of Crater Rays Needs Overhaul

A dating method relied on by planetary geologists needs drastic revision, according to Planetary Science Research Discoveries (PSRD) scientists at the University of Hawaii.  Crater rays are the streaks that extend radially from impact craters.  Previously, planetary scientists assumed they darken over time under bombardment from the solar wind and can be used as indicators […]

Solar Particles Survive Genesis Crash

Scientists are relieved that they have been able to recover enough pieces from the crashed Genesis spacecraft to pursue the science objectives.  JPL Director Charles Elachi said they have snatched victory from the jaws of defeat and are bouncing back from a hard landing.  The highest-priority science goals may still be attainable, at least partially, […]

Are We Lost on a Speck of Cosmic Dust?

A new Copernican revolution seems to be in the works, not another “demotion” of man from the center of the universe, but a promotion back to the ancient idea of plan or purpose for our existence.  The demotions reached their nadir with Carl Sagan’s Cosmos and other books that declared we are nothing special, that […]

Delicate Planet Dance Disturbs Theories

Theorists have been thrown a curve ball with the discovery of a planet orbiting a binary star.  It appears that the gravitational tug on a hypothetical dust disk would have prevented the possibility of a planet forming around one of its members, but Gamma-Cephei has one.  “The formation of a planet in a binary star […]

Earth’s Ugly Sister Can’t Get a Date

Venus is the subject of an interview with David Grinspoon of NASA’s Exobiology Research Program in Astrobiology Magazine, and admits that the entire surface of our hellishly hot sister planet looks young.  It appears the globe was resurfaced almost simultaneously in the relatively recent past. Grinspoon relives the surprises from the Magellan mission: We’ve begun to […]


Among the incomprehensible titles of most papers in the Astrophysical Journal, this one stood out: “Jupiter Formed with More Tar than Ice.”1  Looking at Galileo spacecraft data for oxygen abundance and other things, Katharina Lodders was led to propose the following model: Carbonaceous matter, which has high sticking probabilities, was the agent that sped up […]

“Toy Model” of Planetary Migration Partially Explains Neptune, but Not Uranus

When we last saw Hal Levison (Southwest Research Institute), the genius-at-work was going crazy in fairyland over the difficulties of explaining Uranus and Neptune (see 05/30/2002 headline).  He’s been recovering sanity slowly; he thinks he has a working hypothesis for why Neptune stopped migrating at 30 AU (astronomical unit = sun-earth distance).  Uranus, though, is […]

Our Solar System Is a Rare Gem

As if in time for the upcoming film release of The Privileged Planet (see 06/24/2004 headline), Philip Ball wrote a line for Nature Science Update that would have dismayed Carl Sagan and a host of SETI researchers: “Earth-like planets may be more rare than thought… In cosmic terms, our solar system could be special after […]

Solar Systems Defy Theories

Stuart Ross Taylor (Australian National University, Canberra) feels left behind.  The astronomers have their nice, neat H-R diagrams to explain stars, but no such diagram exists for planetary scientists.  Our hodgepodge collection of planets, moons and small bodies defies classification, to say nothing of the extrasolar planets that have been discovered so far, mostly in […]

Solar System Update

What’s happening at Mars and Saturn?  In this golden age of planetary science, the extraordinary has become commonplace.  Let’s check in and see what the spacecraft have found lately. Mars.  The Mars Exploration Rovers Spirit and Opportunity are still going strong, well past their nominal mission.  Despite a few minor problems (and decreasing sunlight as […]

Titan Shows Its Surface to Cassini

Time to Titan their theories; Cassini scientists are both fascinated and puzzled by surface features coming to light from the first encounter July 2 with Saturn’s large atmosphere-shrouded moon Titan.  At a news conference July 3, some of the initial findings were unveiled: methane clouds hovering over the south pole, linear dark and light markings […]

Tau Ceti a Star for Life to Avoid

Tau Ceti, a star with a dust disk astronomers had hoped might be an example of a planetary system under construction, is more like a war zone.  A press release from the Royal Observatory calls it “Asteroid Alley – an Inhospitable Neighbor.”  Using the James Clerk Maxwell Telescope in Hawaii, the astronomers detected 10 times […]
All Posts by Date