Moons of Mars binary asteroid that separated under tidal forces. Phobos could be a second-generation Solar System object that coalesced in orbit after Mars formed, rather than forming concurrently out of the same birth cloud as Mars. Another hypothesis is that Mars was once surrounded by many Phobos- and Deimos-sized bodies, perhaps ejected into orbit around it by a collision with a large planetesimal. The high porosity of the interior of Phobos (based on the density of 1.88 g/cm, voids are estimated to comprise 25 to 35 percent of Phobos' volume) is inconsistent with an asteroidal origin. Observations of Phobos in the thermal
One Is the Other his superb quartet constantly hint at references from all over the jazz tradition". Steve Greenlee wrote in "JazzTimes" that "The Billy Hart Quartet gets more laidback with each release. "One Is the Other" is the group’s third effort (and second on ECM), and it is a demonstrably looser, freer affair than its predecessors. It’s as though the veteran drummer and his younger compadres—tenor saxophonist Mark Turner, pianist Ethan Iverson, bassist Ben Street—decided they’d proven themselves and can now take more risks with their music". "All About Jazz" correspondent John Kelman observed "with ECM paying increasing attention to North American musicians—with