Astronomers using NASA's Galaxy Evolution Explorer may be closer to knowing why some of the most massive stellar explosions ever observed occur in the tiniest of galaxies
"It's like finding a sumo wrestler in a little 'Smart Car,'" said Don Neill, a member of NASA's Galaxy Evolution Explorer team at the California Institute of Technology in Pasadena, and lead author of a new study published in the Astrophysical Journal."The most powerful explosions of massive stars are happening in extremely low-mass galaxies. New data are revealing that the stars that start out massive in these little galaxies stay massive until they explode, while in larger galaxies they are whittled away as they age, and are less massive when they explode," said Neill.
NASA's Gravity Probe B (GP-B) mission has confirmed two key predictions derived from Albert Einstein's general theory of relativity, which the spacecraft was designed to test.The experiment, launched in 2004, used four ultra-precise gyroscopes to measure the hypothesized geodetic effect, the warping of space and time around a gravitational body, and frame-dragging, the amount a spinning object pulls space and time with it as it rotates.
GP-B determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth. If gravity did not affect space and time, GP-B's gyroscopes would point in the same direction forever while in orbit. But in confirmation of Einstein's theories, the gyroscopes experienced measurable, minute changes in the direction of their spin, while Earth's gravity pulled at them.
Launch pads on Florida's Atlantic Coast face some of the most extreme weather conditions of any launch complex. Everything from lightning and hail to hurricanes and occasional frost make it important to meteorologists to get accurate data to back up their decisions. If they don't, acceptable launch windows could be missed, or worse, unnecessary risks could be taken.
A new comprehensive weather instrumentation system on Launch Pad 39B at Kennedy Space Center is providing up-to-the-second and extremely accurate measurements at different locations and altitudes. The improvements are expected to produce increasingly detailed launch criteria that could lead to more on-time liftoffs for a variety of rockets in the future.
Since the dawn of the space age, humanity has sent 16 robotic emissaries to fly by some of the solar system's most intriguing and nomadic occupants comets and asteroids. The data and imagery collected on these deep-space missions of exploration have helped redefine our understanding of how Earth and our part of the galaxy came to be. But this fall, Mother Nature is giving scientists around the world a close-up view of one of her good-sized space rocks no rocket required.
"On November 8, asteroid 2005 YU55 will fly past Earth and at its closest approach point will be about 325,000 kilometers [201,700 miles] away," said Don Yeomans, manager of NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif. "This asteroid is about 400 meters [1,300 feet] wide – the largest space rock we have identified that will come this close until 2028."
Deadly tornadoes raked across Alabama on April 27, 2011, killing as many as 210 people as of April 29. The hardest-hit community was Tuscaloosa. In an image acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on April 28, three tornado tracks are visible through and around the city.
The tracks are pale brown trails where green trees and plants have been uprooted, leaving disturbed ground. Though faint, the center track runs from southwest of Tuscaloosa, through the gray city, and extends northeast towards Birmingham. Two other tracks run parallel to the center track. The northernmost track is in an area where the National Weather Service reported a tornado, but no tornado was reported in the vicinity of the more visible southern track. In the southern region, strong winds were reported.
NASA's Juno spacecraft has arrived in Florida to begin final preparations for a launch this summer. The spacecraft was shipped from Lockheed Martin Space Systems, Denver, to the Astrotech payload processing facility in Titusville, Fla., today. The solar-powered Juno spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins, structure, atmosphere and magnetosphere. "The Juno spacecraft and the team have come a long way since this project was first conceived in 2003," said Scott Bolton, Juno's principal investigator, based at Southwest Research Institute in San Antonio. "We're only a few months away from a mission of discovery that could very well rewrite the books on not only how Jupiter was born, but how our solar system came into being."
More than 30 years after they left Earth, NASA's twin Voyager probes are now at the edge of the solar system. Not only that, they're still working. And with each passing day they are beaming back a message that, to scientists, is both unsettling and thrilling. The message is, "Expect the unexpected."
"It's uncanny," says Ed Stone of the California Institute of Technology in Pasadena, Voyager Project Scientist since 1972. "Voyager 1 and 2 have a knack for making discoveries." Today, April 28, 2011, NASA held a live briefing to reflect on what the Voyager mission has accomplished--and to preview what lies ahead as the probes prepare to enter the realm of interstellar space in our Milky Way galaxy.
NASA's Swift, Hubble Space Telescope and Chandra X-ray Observatory have teamed up to study one of the most puzzling cosmic blasts yet observed. More than a week later, high-energy radiation continues to brighten and fade from its location. Astronomers say they have never seen anything this bright, long-lasting and variable before. Usually, gamma-ray bursts mark the destruction of a massive star, but flaring emission from these events never lasts more than a few hours. Although research is ongoing, astronomers say that the unusual blast likely arose when a star wandered too close to its galaxy's central black hole. Intense tidal forces tore the star apart, and the infalling gas continues to stream toward the hole.
Remember life before cell phones? Or GPS? Or tablet computers? Kind of hard, isn't it? Air traffic management researchers feel the same way about life before the Future ATM (Air Traffic Management) Concepts Evaluation Tool, or FACET.
FACET is a computer program developed by NASA that generates simulations for managing air traffic scenarios. It provides a "big picture" view of what's happening in the skies overhead. For any given moment in time, it can show thousands of aircraft swarming through our national airspace. With each aircraft represented as a tiny icon, a FACET simulation can look like an "ant farm in the sky," with aircraft clustering around major airports like ants targeting a drop of peanut butter. You may have seen video generated from FACET on the morning news during air travel outlook reports.
After 30 years of spaceflight, more than 130 missions, and numerous science and technology firsts, NASA's space shuttle fleet will retire and be on display at institutions across the country to inspire the next generation of explorers and engineers.
NASA Administrator Charles Bolden on Tuesday announced the facilities where four shuttle orbiters will be displayed permanently at the conclusion of the Space Shuttle Program. Shuttle Enterprise, the first orbiter built, will move from the Smithsonian's National Air and Space Museum Steven F. Udvar-Hazy Center in Virginia to the Intrepid Sea, Air & Space Museum in New York.
To celebrate the 21st anniversary of the Hubble Space Telescope's deployment into space, astronomers at the Space Telescope Science Institute in Baltimore, Md., pointed Hubble's eye at an especially photogenic pair of interacting galaxies called Arp 273.
"For 21 years, Hubble has profoundly changed our view of the universe, allowing us to see deep into the past while opening our eyes to the majesty and wonders around us," NASA Administrator Charles Bolden said."I was privileged to pilot space shuttle Discovery as it deployed Hubble. After all this time, new Hubble images still inspire awe and are a testament to the extraordinary work of the many people behind the world's most famous observatory."
NASA's Mars Reconnaissance Orbiter has discovered the total amount of atmosphere on Mars changes dramatically as the tilt of the planet's axis varies. This process can affect the stability of liquid water, if it exists on the Martian surface, and increase the frequency and severity of Martian dust storms.
Researchers using the orbiter's ground-penetrating radar identified a large, buried deposit of frozen carbon dioxide, or dry ice, at the Red Planet's South Pole. The scientists suspect that much of this carbon dioxide enters the planet's atmosphere and swells the atmosphere's mass when Mars' tilt increases. The findings are published in this week's issue of the journal Science.
The GOES-13 satellite captured images of the powerful weather system that triggered severe weather in the southern U.S. this weekend, and NASA created an animation to show its progression. GOES-13 satellite data showed the strong cold front as it moved eastward from Saturday through Monday and generated tornadoes before moving off-shore into the Atlantic Ocean. NASA's Aqua satellite also captured data from the system and took the temperature of the cold front's cloud tops and revealing severely cold temperatures of some of the thunderstorms.
The Geostationary Operational Environmental Satellite called GOES-13 monitors weather in the eastern half of the U.S. and is operated by NOAA. The NASA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. creates images and animations from the GOES satellite data. The NASA GOES Project created an animation of the satellite imagery from April 15 through April 17 that showed the movement of the powerful cold front through the eastern U.S. In the movie, you can see the low pressure area over Oklahoma on April 15, in a tight circular rotation and watch it move east bringing the cold front with it.
High up in the sky near the poles some 50 miles above the ground, silvery blue clouds sometimes appear, shining brightly in the night. First noticed in 1885, these clouds are known as noctilucent, or "night shining," clouds. Their discovery spawned over a century of research into what conditions causes them to form and vary – questions that still tantalize scientists to this day.
Since 2007, a NASA mission called Aeronomy of Ice in the Mesosphere (AIM) has shown that the cloud formation is changing year to year, a process they believe is intimately tied to the weather and climate of the whole globe."The formation of the clouds requires both water and incredibly low temperatures," says Charles Jackman, an atmospheric scientist at NASA's Goddard Space Flight Center in Greenbelt, Md., who is NASA's project scientist for AIM. "The temperatures turn out to be one of the prime driving factors for when the clouds appear."
To celebrate Earth Day 2011, the Education Office at NASA's Jet Propulsion Laboratory in Pasadena, Calif., is hosting a live Web video chat where your students can ask a NASA/JPL scientist questions emailed in advance. Questions should be on the topic of Earth science. Our chat is best suited for students and afterschool groups in grades 4-6.
Our guest will be NASA/JPL research scientist Annemarie Eldering, who specializes in clouds, aerosols and trace gases in Earth's atmosphere. She is currently the deputy project scientist for the Orbiting Carbon Observatory-2, a NASA satellite mission now in development that will measure atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth's climate.
If you've ever stood in front of a hot stove, watching a pot of water and waiting impatiently for it to boil, you know what it feels like to be a solar physicist. Back in 2008, the solar cycle plunged into the deepest minimum in nearly a century. Sunspots all but vanished, solar flares subsided, and the sun was eerily quiet.
"Ever since, we've been waiting for solar activity to pick up," says Richard Fisher, head of the Heliophysics Division at NASA Headquarters in Washington DC. "It's been three long years."Quiet spells on the sun are nothing new. They come along every 11 years or so it's a natural part of the solar cycle. This particular solar minimum, however, was lasting longer than usual, prompting some researchers to wonder if it would ever end.
Astronomers across the globe can now sift through hundreds of millions of galaxies, stars and asteroids collected in the first bundle of data from NASA's Wide-field Infrared Survey Explorer (WISE) mission.
"Starting today thousands of new eyes will be looking at WISE data, and I expect many surprises," said Edward (Ned) Wright of UCLA, the mission's principal investigator. WISE launched into space on Dec. 14, 2009 on a mission to map the entire sky in infrared light with greatly improved sensitivity and resolution over its predecessors. From its polar orbit, it scanned the skies about one-and-a-half times while collecting images taken at four infrared wavelengths of light. It took more than 2.7 million images over the course of its mission, capturing objects ranging from faraway galaxies to asteroids relatively close to Earth.
A flat, light-toned rock on Mars visited by NASA's Mars Exploration Rover in 2005 informally bears the name of the first human in space, Yuri Gagarin, who rode into orbit in the Soviet Union's Vostok-1 spacecraft on April 12, 1961.
The team using Opportunity to explore the Meridiani Planum region of Mars since 2004 chose "Gagarin" for what they would call the rock that the rover examined beside "Vostok" crater. A target for close-up examination on Gagarin is called "Yuri."To commemorate Gagarin's flight, a color image of the rock on Mars has been posted, here. The image combines frames taken through three different filters by Opportunity's panoramic camera.
Assembly and testing of NASA's Mars Science Laboratory spacecraft is far enough along that the mission's rover, Curiosity, looks very much as it will when it is investigating Mars.
Testing continues this month at NASA's Jet Propulsion Laboratory, Pasadena, Calif., on the rover and other components of the spacecraft that will deliver Curiosity to Mars. In May and June, the spacecraft will be shipped to NASA Kennedy Space Center, Fla., where preparations will continue for launch in the period between Nov. 25 and Dec. 18, 2011.
Forty-five years after its first Saturn V rocket stage test and 35 years after its first space shuttle main engine test, the A-2 Test Stand at NASA’s John C. Stennis Space Center achieved a milestone in preparation for its third major rocket engine test project.
A facility readiness review in mid-March indicated all major modifications have been completed on the historic A-2 stand to begin testing the next-generation J-2X rocket engine this summer.The new test project comes as Stennis celebrates its 50th anniversary year. On Oct. 26, 1961, NASA publicly announced plans to build the south Mississippi facility to test the massive Saturn V rocket stages for the Apollo Program.
Mary Cleave left the NASA astronaut corps in the early 1990s to make a rare jump from human spaceflight to Earth science. She was going to work on an upcoming mission to measure gradations in ocean color something she had actually seen from low-Earth orbit with her own eyes. From space, differing densities of phytoplankton and algae and floating bits of plant life reveal themselves as so many blues and greens. For Cleave, a former environmental engineer, the attraction was simple.
"We were going to measure green slime on a global scale," said Cleave, now retired from her varied NASA career.That is exactly what SeaWiFS Sea viewing Wide Field of view Sensor did for over 13 years, until it recently stopped communicating with ground-based data stations and after several months of intensive efforts at recovery, was declared unrecoverable in February.
Like forensic scientists examining fingerprints at a cosmic crime scene, scientists working with data from NASA's Cassini, Galileo and New Horizons missions have traced telltale ripples in the rings of Saturn and Jupiter back to collisions with cometary fragments dating back more than 10 years ago.
The ripple-producing culprit, in the case of Jupiter, was comet Shoemaker-Levy 9, whose debris cloud hurtled through the thin Jupiter ring system during a kamikaze course into the planet in July 1994. Scientists attribute Saturn's ripples to a similar object likely another cloud of comet debris plunging through the inner rings in the second half of 1983. The findings are detailed in a pair of papers published online today in the journal Science.
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On March 29, 1807, German astronomer Heinrich Wilhelm Olbers spotted Vesta as a pinprick of light in the sky. Two hundred and four years later, as NASA's Dawn spacecraft prepares to begin orbiting this intriguing world, scientists now know how special this world is, even if there has been some debate on how to classify it.
Vesta is most commonly called an asteroid because it lies in the orbiting rubble patch known as the main asteroid belt between Mars and Jupiter. But the vast majority of objects in the main belt are lightweights, 100-kilometers-wide (about 60-miles wide) or smaller, compared with Vesta, which is about 530 kilometers (330 miles) across on average. In fact, numerous bits of Vesta ejected by collisions with other objects have been identified in the main belt.
At 33 minutes after 4 p.m. PDT today, NASA's Stardust spacecraft finished its last transmission to Earth. The transmission came on the heels of the venerable spacecraft's final rocket burn, which was designed to provide insight into how much fuel remained aboard after its encounter with comet Tempel 1 in February.
"Stardust has been teaching us about our solar system since it was launched in 1999," said Stardust-NExT project manager Tim Larson from NASA's Jet Propulsion Laboratory in Pasadena, Calif. "It makes sense that its very last moments would be providing us with data we can use to plan deep space mission operations in the future."
NASA's Stardust spacecraft sent its last transmission to Earth at 4:33 p.m. PDT (7:33 p.m. EDT) Thursday, March 24, shortly after depleting fuel and ceasing operations. During a 12-year period, the venerable spacecraft collected and returned comet material to Earth and was reused after the end of its prime mission in 2006 to observe and study another comet during February 2011.
The Stardust team performed the burn to depletion because the comet hunter was literally running on fumes. The depletion maneuver command was sent from the Stardust-Next mission control area at Lockheed Martin Space Systems in Denver. The operation was designed to fire Stardust's rockets until no fuel remained in the tank or fuel lines. The spacecraft sent acknowledgment of its last command from approximately 312 million kilometers (194 million miles) away in space.
The discovery of a pattern of X-ray “stripes” in the remains of an exploded star may provide the first direct evidence that a cosmic event can accelerate particles to energies a hundred times higher than achieved by the most powerful particle accelerator on Earth.
This result comes from a very long observation of the Tycho supernova remnant with NASA's Chandra X-ray Observatory. It could explain how some of the extremely energetic particles bombarding the Earth, called cosmic rays, are produced. “We've seen lots of intriguing structures in supernova remnants, but we’ve never seen stripes before,” said Kristoffer Eriksen of Rutgers University, who led the study. “This made us think very hard about what's happening in the blast wave of this powerful explosion.
Recent data from NASA's Cassini spacecraft show that the variation in radio waves controlled by the planet's rotation is different in the northern and southern hemispheres. Moreover, the northern and southern rotational variations also appear to change with the Saturnian seasons, and the hemispheres have actually swapped rates. These two radio waves, converted to the human audio range.
"These data just go to show how weird Saturn is," said Don Gurnett, Cassini's radio and plasma wave science instrument team lead and professor of physics at the University of Iowa, Iowa City. "We thought we understood these radio wave patterns at gas giants, since Jupiter was so straightforward. Without Cassini's long stay, scientists wouldn't have understood that the radio emissions from Saturn are so different."
