
Spirit, the space-craft created by NASA has landed on Mars. At first Spirit started coming towards Mars at 12,000 miles an hour. Scientist could do nothing but wait. Then Spirit started slowing down to 4,000 miles an hour, just as scientists planned. Airbags popped out of the space-craft to protect itself. Now the only question left was will Spirit land safely? The missions manager, Peter Theisinger, knew that the last few minutes of Spirits long trip would either break or make the mission possible. At first, the scientists had no signal.
Then in Pasadena, California, 105 million miles away from Mars, a "cheer rang out." All the Scientist were shouting "We see it!" The radio signal had shown that Spirit had landed. It showed that Spirit had a very bumpy landing on Mars.They celebrated by crying, and giving each other high fives.Peter Theisinger quotes, "This was seven months of boredom followed by six minutes of sheer terror."
Shortly after it landed, Spirit started sending information and photographs about its journey. Spirit's first picture of Mars was was taken on January of rocks. Another picture Spirit took was a 3-D picture of Mars. The first 3-D picture and the most clearest picture ever. Spirit has nine cameras. We have made 33 missions to Mars since 1960, and 22 of them crashed and failed the mission. To learn more about the Spirit Rover click on the link below.
Spirit had to make 8 steps to land on Mars. This is how Spirit, the space-craft landed on the planet Mars.
First Spirit had to slow down The speed dropped from 12,000 miles an hour to 4,000 miles an hour. A parachute popped out of Spirit to help it slow down even more. When Spirit got 50 feet away from Mars a rocket stopped it completely in midair. Spirit, which was protected all around by air bags, released from the parachute and fell toward Mar's surface. Still protected by air bags, The 1,175 pound space-craft bounced on the surface of Mars for about 15 times until coming to a complete stop. Some special tools helped deflate the air bags and let the space-craft out. Spirit unfolded the solar panels to gather energy for searching the planet. After landing the rover is ready to examine and take pictures of Mar's surface.

Firestorm of Star Birth Seen in a Local Galaxy View all images December 4th 2003 This festively colorful nebula, called NGC 604, is one of the largest known seething cauldrons of star birth seen in a nearby galaxy. NGC 604 is similar to familiar star-birth regions in our Milky Way galaxy, such as the Orion Nebula, but it is vastly larger in extent and contains many more recently formed stars. This monstrous star-birth region contains more than 200 brilliant blue stars within a cloud of glowing gases some 1,300 light-years across, nearly 100 times the size of the Orion Nebula. To learn more click on the link below.
Background information
Mars's 'Close Encounter' with Earth Skip down to: Hubble's Role
in Exploring Mars Mars is hurtling toward Earth at a rate of 22,000
miles an hour (36,000 kilometers an hour)! Not to worry. The two
planets are just setting the stage for their closest encounter
in recorded human history.
On August 27, 2003, the third and fourth planets from the Sun will be within 35 million miles (56 million kilometers) of each other. The reason the two planets will be unusually close: Opposition. Approximately every two years, the Earth's orbit catches up to Mars's orbit, aligning the Sun, Earth, and Mars in a straight line, so that Mars and the Sun are on "opposing" sides of Earth. This phenomenon is a result of the difference in orbital periods between Earth's orbit and Mars's orbit. While Earth takes the familiar 365 days to travel once around the Sun, Mars takes 687 Earth days to make its trip around the Sun.
As a result, Earth can manage to make almost two full orbits in the time it takes Mars to make just one, resulting in the occurrence of Martian opposition every 26 months. This year's opposition will be especially memorable, however, because the two planets will come closer to each other than they have been in nearly 60,000 years! This rare encounter is also due to the difference in Earth's orbit compared with that of Mars.
While Earth is on a very near-circular orbit around the Sun, Mars sweeps out a large ellipse over its orbit. As a result, there are times when the planet is farthest from the Sun (aphelion) and when it is closest to the Sun (perihelion). These orbital dynamics result in Earth-Mars approaches ranging between 35 and 63 million miles. The situation the two planets are now facing is that Earth is near aphelion and Mars is at perihelion.
In other words, Earth is farther out than normal, while Mars is moving closer to the Sun than usual. While there is no danger of the two planets colliding, they will be a mere 34.7 million miles (55.8 million kilometers) apart, enough to make the Red Planet appear slightly larger and brighter in our nighttime sky. During past oppositions, many famous observations were made of the Red Planet. An opposition in November 1659 made it possible for Christiaan Huygens, a Dutch scientist and mathematician, to see and sketch the first accurate drawings of the Martian surface, which showed a major dark marking on the planet now known as Syrtis Major.
Although farther away than usual during the opposition of 1666, Mars offered Gian Cassini the first view of its polar ice caps; Cassini was also able to calculate the rotation period of Mars from his opposition observations. Later, Schiaparelli made perhaps the most famous observation of Mars and its "canals," which, due to a misinterpretation, set the stage for speculation about life on Mars. Following that, during the perihelic opposition of 1877, Mars came close enough to Earth for Asaph Hall to resolve Mars's two small moons, which he named Phobos and Deimos. The shorter-than-usual separation of these planets also makes this summer the ideal time to launch scientific expeditions to Mars. With a shorter distance to traverse, not as much fuel is needed to boost the mission to Mars, which leaves room for more valuable scientific instruments. NASA plans to launch a pair of Mars Exploration Rovers to investigate the Martian surface over the summer, as does the European Space Agency, with Beagle 2. To learn More go to the site below.
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Trailing 200,000-light-year-long streamers of seething gas, a
galaxy that was once like our Milky Way is being shredded as it
plunges at 4.5 million miles per hour through the heart of a distant
cluster of galaxies.
In this unusually violent collision with ambient cluster gas, the galaxy is stripped down to its skeletal spiral arms as it is eviscerated of fresh hydrogen for making new stars. The galaxy's untimely demise is offering new clues to solving the mystery of what happens to spiral galaxies in a violent universe. Views of the early universe show that spiral galaxies were once much more abundant in rich clusters of galaxies. But they seem to have been vanishing over cosmic time. Where have these "missing bodies" gone?
Astronomers are using a wide range of telescopes and analysis techniques to conduct a "CSI" or Crime Scene Investigator-style look at what is happening to this galaxy inside its cluster's rough neighborhood. "It's a clear case of galaxy assault and battery," says William Keel of the University of Alabama. "This is the first time we have a full suite of results from such disparate techniques showing the crime being committed, and the modus operandi." Keel and colleagues are laying out the "forensic evidence" of the galaxy's late life, in a series of presentations today in Atlanta, Ga., at the 203rd meeting of the American Astronomical Society. Astronomers have assembled the evidence by combining a variety of diagnostic observations from telescopes analyzing the galaxy's appearance in X-ray, optical, and radio light.
Parallel observations at different wavelengths trace how stars, gas, and dust are being tossed around and torn from the fragile galaxy, called C153. Though such "distressed" galaxies have been seen before, this one's demise is unusually swift and violent. The galaxy belongs to a cluster of galaxies that slammed into another cluster about 100 million years ago. This galaxy took the brunt of the beating as it fell along a trajectory straight through the dense core of the colliding cluster. "This helps explain the weird X-ray and radio emissions we see," says Keel. "The galaxy is a laboratory for studying how gas can be stripped away when it flies through the hot cluster gas, shutting down star birth and transforming the galaxy." The first suggestion of galactic mayhem in this cluster came in 1994 when the Very Large Array radio telescope near Socorro, N.M., detected an unusual number of radio galaxies in the cluster, called Abell 2125.
Radio sources
trace both star formation and the feeding of central black holes
in galaxy clusters. The radio observations also showed that C153
stood out from the other galaxies as an exceptionally powerful
radio source. Keel's team began an extensive program of further
observations to uncover details about the galaxies. "This
was designed to see what the connection could possibly be between
events on the 10-million-light-year scale of the cluster merger
and what happens deep inside individual galaxies," says Keel.
X-ray observations from the ROSAT satellite (an acronym for the
Roentgen Satellite) demonstrated that the cluster contains vast
amounts of 36-million-degree Fahrenheit (20-million-degree Kelvin)
gas that envelops the galaxies. The gas is concentrated into two
main lumps rather than smoothly distributed across the cluster,
as is more commonly the case.
This bolstered the suspicion that two galaxy clusters are actually colliding. In the mid-to-late 1990s astronomers turned the Mayall 4-meter telescope and the WIYN 3.5-meter telescope at the Kitt Peak National Observatory on the cluster to analyze the starlight via spectroscopy. They found many star-forming systems and even active galactic black holes fueled by the collision. The disintegrating galaxy C153 stood out dramatically when the KPNO telescopes were used to photomap the cluster in color. Astronomers then trained NASA's Hubble Space Telescope (HST) onto C153 and resolved a bizarre shape. They found that the galaxy looks unusually clumpy with many young star clusters and chaotic dust features. Besides the disrupted features in the galaxy's disk, HST also showed that the light in the tail is mostly attributed to recent star formation, providing a direct link to the stripping of the galaxy as it passed through the cluster core.
Gas compressed along the galaxy's leading edge, like snow before a plow, ignited a firestorm of new star birth. Evidence of recent star formation also comes from the optical spectrum obtained at the 10-meter Gemini North telescope in Hawaii. The spectrum allows the researchers to estimate the time since the most recent burst of star formation. This conclusion was further bolstered when the Mosaic camera on Kitt Peak's Mayall telescope found a very long tail of extended gas coming off the galaxy. The tail was apparently generated in part by a hurricane of stellar winds boiling off the new star-birth regions and being blown backwards as the galaxy streaks through the surrounding hot gas of the cluster.
Spectroscopic
observations with the Gemini telescope allowed astronomers to
age-date the starburst. They find that 90 percent of C153's blue
light is from a population of stars that are 100 million years
old. This age corresponds to the time the galaxy should have gone
careening through the densest gas in the cluster core. The Gemini
spectroscopic observations show the stars are in a regular pattern
of orbital motion around the center, as usual for disk galaxies.
However, there are multiple widespread clouds of gas moving independently of the stars. "This is an important clue that something beyond gravitational forces must be at work, since stars and gas respond the same way to purely gravitational forces," says Keel. "In other words, the galaxy's gas doesn't know what the stars are doing." NASA's Chandra X-ray Observatory discovered that the cooler clouds detected with optical telescopes and an associated radio feature are embedded in a much larger multi-million-degree trail of gas.
Chandra's data indicate that this hot gas was probably enriched in heavy elements by the starburst and driven out of the galaxy by its supersonic motion through the much larger cloud of gas that pervades the cluster. Collectively, these observations offer evidence that the ram pressure of external gas in the cluster is stripping away the galaxy's own gas. This process has long been hypothesized to account for the forced evolution of cluster galaxies. Its aftermath has been seen in several ways.
Some nearby examples, Seyfert's Sextet and Stefan's Quintet, are tight clusters that show the aftermath of high-velocity collisions. The galaxy C153 is destined to lose the last vestiges of its spiral arms and become a bland S0-type galaxy having a central bulge and disk, but no spiral-arm structure. These types of galaxies are common in the dense galaxy clusters seen today. Astronomers plan to make new observations with Gemini again in 2004 to study the dynamics of the gas and stars in the tail. The science team members are William Keel (University of Alabama), Frazer Owen (National Radio Astronomy Observatory), Michael Ledlow (Gemini Observatory), and Daniel Wang (University of Massachusetts).
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