Sunday: February 25, 2001   0042 GMT Glitch with Titan 4 rocket resolved, launch date set The Titan 4B rocket has been cleared for liftoff Tuesday with the Milstar communications satellite cargo, the Air Force announced Saturday after isolating and correcting a problem with the vehicle's first stage telemetry relay system.    MISSION STATUS CENTER    LIVE LAUNCH WEBCAST Galaxy groups surveyed beyond local neighborhood In a cosmically short time, probably in a few billion years, our Milky Way galaxy will smash into the Andromeda galaxy. Pulled together by gravity, the two spiral galaxies will violently merge perhaps into another kind of galaxy, an elliptical galaxy.    FULL STORY DAILY BRIEFING  Other stories making news today How did matter come to dominate the universe? -- The seemingly unremarkable fact that the universe is full of matter turns out to be something physicists can't quite account for. According to the big bang theory, equal amounts of matter and antimatter were created at the birth of the universe, but precious little antimatter is to be found in the universe today. Saturday: February 24, 2001   0239 GMT Space station residents take weekend getaway The three-man Expedition One crew living aboard the international space station departed the orbiting outpost for a short time this morning to move their Soyuz capsule to a different docking port.    MISSION STATUS CENTER    VIDEO: ANIMATION OF RELOCATION    SOYUZ RELOCATION TIMELINE    GRAPHIC SHOWING SOYUZ MOVE Johnson Space Center chief George Abbey ousted NASA announced late Friday that George Abbey, one of the most powerful and enigmatic figures in the space program, was being replaced as director of the Johnson Space Center. Abbey, who becomes a special advisor to the NASA Administrator, was ousted in the wake of huge cost overuns in the international space station program.    NASA NEWS RELEASE Titan 4 launch delayed Launch of the $455 million Titan 4B rocket carrying a $750 million Milstar military communications satellite has been pushed back to Tuesday at the earliest. The extra time is needed so technicians can further study and fix a problem with the rocket's telemetry system.    MISSION STATUS CENTER    LIVE LAUNCH WEBCAST NEAR mission extended through end of the month NASA granted an additional four-day extension for the Near Earth Asteroid Rendezvous (NEAR) Shoemaker mission on Friday so that the spacecraft can return additional data from the surface of the asteroid Eros through the end of the month.    FULL STORY    MISSION STATUS CENTER Friday: February 23, 2001   0401 GMT Asteroid or comet blamed for mass extinction Earth's most severe mass extinction - an event 250 million years ago that wiped out 90 percent of all marine species and 70 percent of land vertebrates - was triggered by a collision with a comet or asteroid, according to new findings.    FULL STORY Titan 4 rocket prepped for weekend blastoff Pre-flight preparations continue at Cape Canaveral where the Air Force and Lockheed Martin launch team is getting postured to start the countdown later today for Saturday's blastoff of a Titan 4B rocket.    MISSION STATUS CENTER    LIVE LAUNCH WEBCAST SOHO watches kamikaze comet as it plunges into Sun A comet that fell into the Sun on February 7 was tracked by two different instruments on the ESA-NASA SOHO spacecraft, enabling scientists to characterize it quite precisely. This was just one of nearly 300 comets discovered by SOHO since 1996!    FULL STORY DAILY BRIEFING  Other stories making news today New telescope makes black hole discovery -- Working independently, two teams of astronomers have used the new 6.5-meter telescope at the MMT Observatory on Mount Hopkins, Ariz., to discover a massive black hole -- the first ever found in the galactic halo, thousands of light years above the Milky Way galactic plane. Thursday: February 22, 2001   0332 GMT Galileo's camera suffers problem, some pictures lost Engineers are narrowing down possible causes for an intermittent problem with the camera on NASA's Galileo spacecraft that may be related to effects of Jupiter's radiation belts.    FULL STORY Titan 4 rocket ready to fly After an extended wait on the launch pad to ensure its guidance computer brain was free of defects, an Air Force Titan 4B rocket is finally cleared for blastoff this weekend with the fourth Milstar communications satellite.    MISSION STATUS CENTER Dusty space donut caught with surprise companion The innermost structure of the donut-shaped dust cloud surrounding a massive young star and the first glimpse of its previously unknown companion star was seen by applying new technology to the Keck telescope in Hawaii.    FULL STORY Students uncover baffling Martian boulders In a case of beginner's luck, a group of international students, who won the chance to image Mars with a NASA spacecraft camera, have stumbled upon a surprising cluster of dark-colored boulders situated in the middle of light-colored terrain.    FULL STORY    EARLIER STORY Wednesday: February 21, 2001   0324 GMT Atlantis takes detour to Mojave Desert landing Running two days late, the shuttle Atlantis dropped out of a cloudy Mojave Desert sky and glided to a smooth landing Tuesday at Edwards Air Force Base to wrap up an extended space station assembly flight.    FULL STORY    MISSION STATUS CENTER    DETAILED ENTRY TIMELINE    LANDING GROUND TRACK More mission coverage here:       Russian Mir space station reaches 15th anniversary The Mir space station marked its 15th anniversary in orbit on Tuesday, one day after the captains of the Russian space program defended their decision to deorbit the pioneering outpost.    FULL STORY DAILY BRIEFING  Other stories making news today Research determines how plants tell which way is up -- Scientists are expanding the understanding of how gravity affects plant growth, which has implications for agriculture and space travel. Extended space missions will need to use plants and know how gravity affects the growth of plants. Tuesday: February 20, 2001   0357 GMT Weather forces Atlantis to remain in space again For the second day running, unacceptable weather at Kennedy Space Center caused NASA to scrap plans to bring space shuttle Atlantis back to Earth on Monday. The shuttle remained in orbit in hopes of better conditions in Florida on Tuesday.    FULL STORY    MISSION STATUS CENTER    DETAILED ENTRY TIMELINE    LANDING GROUND TRACKS Swedish satellite launches aboard Cold War relic A decommissioned ballistic missile lifted off from the Svobodny Cosmodrome in Russia's far east at 0848:27 GMT, successfully placing a small Swedish scientific satellite into orbit.    FULL STORY Students image Martian valleys and boulders This image was taken in the fretted terrain area located in the middle latitudes of Mars. Interesting features in this area are dunes, valleys, and mysterious black boulders.    FULL STORY DAILY BRIEFING  Other stories making news today Space station astronauts need to be versatile -- Although working in space is still not routine, it is far more frequent than it once was. One reason being the construction of the International Space Station by the United States, Russia, Canada, Japan and 10 European Space Agency Member States. Galileo beams home recorded observations -- It is going to be yet another quiet week for the Galileo spacecraft. Long cruise periods between encounters can be that way! On Tuesday, the spacecraft performs standard maintenance on its tape recorder system. Playback of the data stored on the tape from the December 27 flyby of Ganymede continues. Monday: February 19, 2001   1500 GMT High winds keep shuttle Atlantis in space till Monday High crosswinds at the Kennedy Space Center blocked two back-to-back landing attempts by shuttle Atlantis Sunday and forced entry flight director Leroy Cain to extend the mission by one day in hopes of better weather Monday.    FULL STORY    MISSION STATUS CENTER    DETAILED ENTRY TIMELINE    EARLIER STORY    LANDING GROUND TRACKS You can't have a galaxy without a black hole Galaxies and black holes are so intimately connected that it is almost impossible to find one without the other. Over the last decade, a team of researchers have detected massive black holes in all but one of the 30 spiral galaxies they surveyed.    FULL STORY DAILY BRIEFING  Other stories making news today Arianespace preps for first Ariane 5 launch of 2001 -- A powerful Ariane 5 rocket is being readied to fly to space early next month with two commercial communications satellites. Flight 140 will be the third Ariane rocket launch of 2001 and the first for Ariane 5.				Hubble poster The Hubble Space Telescope's majestic view of the Eskimo Nebula. This spectacular poster is available now from the Astronomy Now Store.    MORE Earlier news Feb. 12-18: NEAR probe survives historic landing on asteroid Eros; Atlantis departs station after flawless lab delivery; More new Mars pictures; Launches of XM radio satellites shuffled. Feb. 5-11: Space station meets its 'Destiny' as shuttle delivers lab; Several new Mars pictures; X-33 engines pass test; Europe's Ariane 4 carries out military mission. Jan. 29-Feb. 4: Ant-like space structure previews death of our Sun; Boeing Delta 2 rocket lofts another GPS satellite; Mars Global Surveyor completes prime mission; What's that? Probe sees strange surfaces on Mars; EUVE shut down; Pin-pointing black holes in distant galaxies. More news  See our weekly archive of space news. 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