Astronomy Now Online

Saturn's aurora defy scientists' expectations
Feb 16:  The dancing light of the auroras on Saturn behaves in ways different from how scientists have thought possible for the last 25 years. New research by a team of U.S. and European planetary scientists has overturned theories about how Saturn's magnetic field behaves and how its auroras are generated.
Outsider moon
Feb 15:  Reflected light from Saturn dimly illuminates the night side of the cratered moon Mimas in this Cassini image. Above, the outer edges of the planet's main rings show some interesting details. Several thin ringlets comprising the F ring are nicely visible, and the bright core of the ring displays a few twisted knots.
Ring beholds a delicate flower, Spitzer reveals
Feb 14:  NASA's Spitzer Space Telescope finds a delicate flower in the Ring Nebula, as shown in this image. The outer shell of this planetary nebula looks surprisingly similar to the delicate petals of a camellia blossom.
Gamma-ray bursts detected by new satellite pinpointed
Feb 14:  Cosmic gamma-ray bursts produce more energy in the blink of an eye, than the Sun will release in its entire lifetime. These short-lived explosions appear to be the death throes of massive stars, and, many scientists believe, mark the birth of black holes. Testing these ideas has been difficult, however, because the bursts fade so quickly and rapid action is required.
First stellar outcast discovered by astronomers
Feb 12:  Astronomers have reported the discovery of a star leaving our galaxy, speeding along at over 1.5 million miles per hour. This incredible speed likely resulted from a close encounter with the Milky Way's central black hole, which flung the star outward like a stone from a slingshot. So strong was the event that the speedy star eventually will be lost altogether, travelling alone in the blackness of intergalactic space.
Scientists reveal smallest extra-solar planet yet found
Feb 11:  Penn State's Alex Wolszczan, the discoverer in 1992 of the first planets ever found outside our solar system, now has discovered the smallest planet yet detected, in that same far-away planetary system. Immersed in an extended cloud of ionised gas, the new planet orbits a rapidly spinning neutron star called a pulsar.
Dead-on view of Herschel
Feb 10:  Saturn's moon Mimas has many large craters, but one named Herschel dwarfs all the rest. 80 miles in diameter with a prominent central peak, Herschel is seen here almost exactly on the terminator. The crater is the moon's most prominent feature, and the impact that formed it probably nearly destroyed Mimas.
Extrasolar planets may have diamond layers
Feb 9:  Some extrasolar planets may be made substantially from carbon compounds, including diamond, according to a report presented this week at the conference on extrasolar planets. Earth, Mars and Venus are "silicate planets" consisting mostly of silicon-oxygen compounds. Astrophysicists are proposing that some stars in our galaxy may host "carbon planets" instead.
First measurement of Titan's winds from Huygens
Feb 9:  Scientists have measured the speed of the winds faced by Huygens during its descent through the atmosphere of Titan. The winds are weak near the surface and increase slowly with altitude up to about 37 miles, becoming much rougher higher up where significant vertical wind shear may be present.
Beginnings of 'mini' solar system discovered
Feb 8:  NASA's Spitzer Space Telescope has spotted a dusty disc of planet-building material around an extraordinarily low-mass brown dwarf, or "failed star."
Saturn's blue cranium
Feb 8:  Saturn's northern hemisphere is presently a serene blue, more befitting of Uranus or Neptune, as seen in this natural colour image from Cassini. Shadows cast by the rings surround the pole, looking almost like dark atmospheric bands.
Mimas blues
Feb 8:  The moon Mimas drifts along in its orbit against the azure backdrop of Saturn's northern latitudes in this true colour view. The long, dark lines on the atmosphere are shadows cast by the planet's rings.
NASA budget proposal kills Hubble repair mission
Feb 8:  President George W. Bush's proposed 2006 budget would give NASA a modest funding increase, but would cancel a proposed robotic servicing mission to the Hubble Space Telescope as well as a nuclear-powered spacecraft to explore the moons of Jupiter.
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Discovery of Pluto reaches 75th anniversary
Feb 7:  The planet Pluto turns 75 this month. Clyde Tombaugh discovered the ninth planet in the solar system on the afternoon of February 18th, 1930 while he meticulously examined a pair of deep sky photographs at Lowell Observatory.
New Arecibo sky survey may find 'dark galaxies'
Feb 5:  Fitted with its new compound eye on the heavens, the Arecibo Observatory telescope, the world's largest and most sensitive single-dish radio telescope, is beginning a years-long survey of distant galaxies, perhaps discovering elusive "dark galaxies" — galaxies that are devoid of stars.
Upper limit to stellar mass found
Feb 5:  New research from the University of Michigan shows that there may be an upper limit to the mass of a star, somewhere around 120 to 200 times bigger than our Sun. Knowing that there may be a limit to a star's mass answers a fundamental question, but raises a raft of other issues about what limits their mass, said Sally Oey, assistant professor of astronomy.
Saturn has strange hot spot
Feb 4:  Astronomers using the Keck I telescope in Hawaii are learning much more about a strange, thermal "hot spot" on Saturn that is located at the tip of the planet's south pole. In what the team is calling the sharpest thermal views of Saturn ever taken from the ground, the new set of infrared images suggest a warm polar vortex at Saturn's south pole — the first to ever be discovered in the solar system.
Light continues to echo 3 years after stellar outburst
Feb 3:  The Hubble Space Telescope's latest image of the star V838 Monocerotis reveals dramatic changes in the illumination of surrounding dusty cloud structures. The effect, called a light echo, has been unveiling never-before-seen dust patterns ever since the star suddenly brightened for several weeks in early 2002.
Lost and found: Chandra locates missing matter
Feb 2:  NASA's Chandra X-ray Observatory has discovered two huge intergalactic clouds of diffuse hot gas. These clouds are the best evidence yet that a vast cosmic web of hot gas contains the long-sought missing matter — about half of the atoms and ions in the universe.
Swift sees Pinwheel Galaxy as satellite goes operational
Feb 1:  The Swift satellite's Ultraviolet/Optical Telescope has seen first light, capturing an image of the Pinwheel Galaxy, long loved by amateur astronomers as the "perfect" face-on spiral galaxy.