Feb 12, 2015 Comets are not the only objects with tails. Since comets and their characteristics are in the news, it is good to remember that not all objects with tails are comets. Venus, for example, possesses a filamentary comet-like tail that stretches for millions of kilometers. Indeed, at its…
Feb 11, 2015 Rather than clouds of frigid dust and gas, twisted filaments suggest electric currents in space. Temperatures near absolute zero show up in the infrared image in blue false color in the image at the top of the page. The Eagle nebula is an active “star nursery”…
Feb 9, 2015 Plumes of water vapor from Enceladus are not caused by friction. Saturn’s moons are difficult explain when conventional ideas about the composition and age of the Solar System are considered. They vary in composition, orbital inclination, size, and mass. With 62 moons now identified, and 53 of…
Feb 05, 2015 More electric biology. A previous Picture of the Day described the way that some single-celled organisms make use of charge exchange in order to drive their flagella. Rather than the conversion of ATP, they move protons along special cellular structures, converting that flow of electric charge into…
Feb 03, 2015 Extensive deposits of various compounds are found on Mars. The idea that there might once have been liquid oceans on Mars has been bandied about for hundreds of years. The Mars Science Laboratory, known as Curiosity, was sent to Mars in order to look for signs of…
Jan 29, 2015 Shockwave: a compressional wave of high amplitude caused by a shock (as from an earthquake or explosion) to the medium through which the wave travels. The plasmasphere of Saturn is highly energetic, enough so that, when the Cassini orbiter sent images to Earth, lightning up to a million times…
Jan 27, 2015 A salty ocean beneath Titan’s ice? NASA launched the Cassini-Huygens spacecraft On October 15, 1997. The bus-sized, six ton payload was the largest deep space mission ever deployed, requiring a seven year journey to Saturn. Cassini-Huygens entered orbit around Saturn on June 30, 2004. Its name has…
Jan 26, 2015 Galaxy clusters are thought to be pulled by a force emanating from “beyond the horizon” of the Universe. Astronomers believe that the Universe is expanding at an ever accelerating rate. Contemporary theories suggest that galaxies are receding from us because they started out receding from us…
Jan 23, 2015 Astronomical theories predict a white dwarf star that can not be found. In the nuclear view, a planetary nebula is the result of a dying star that has exhausted its hydrogen/helium fuel supply and collapsed under gravitational compression. The stellar implosion rebounds off the core, throwing…
Jan 22, 2014 So-called “lava coils” are present on Mars. “Ares…who whirl your fiery sphere among the planets in their sevenfold courses through the aether wherein your blazing steeds ever bear you above the third firmament of heaven…” — Homer, Hymn 8 to Ares (exert) A previous Picture of the…
