Five Solar Eruptions in 2 Days – Beautiful High Latitude Aurora Result From Active Solar Weekend

UPDATE 02.27.12: Beautiful High Latitude Aurora Sighted
The weak CME impact on February 26, 2012 did cause some aurora in high latitude locations after a modest start. The above image was captured over Muonio, Finland late last night, a gorgeous ending to a weekend of spectacular solar eruptions and CMEs.
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UPDATE 02.26.12: Weak CME Impact

Though the February 24, 2012 solar eruption provided quite a show, the associated coronal mass ejection (CME) that impacted Earth's magnetic field on Feb. 26, 2012 around 4:00pm EST (2100 UT) was weak and does not appear set to cause a strong geomagnetic storm.

From February 23 through February 24 our sun produced an astonishing five solar eruptions, launched from the top, bottom, left and right sides of the solar disk. Four of those eruptions came in just a 24 hour period.

One of the eruptions, a large snaking magnetic filament, erupted during the early hours of February 24, 2012 and launched the first of two coronal mass ejections (CME) in Earth’s direction. Analysis by scientist at the Goddard Space Weather Lab shows that this CME cloud will strike Earth's magnetic field on February 26, 2012 near 8:30am EST (+/- 7 hr). Geomagnetic storms and aurora are possible when the CME arrives.

The filament eruption, as seen in the video above taken by the Solar Dynamic Observatory (SDO) in extreme ultraviolet wavelength, forms a visible split in the sun's atmosphere, where plasma races away in waves in opposite directions. The divide stretches the length of the original filament location, almost 248,500 miles (400,000 km).

Solar filaments are darker, cooler solar material floating above the sun's surface, suspended by magnetic forces. When they appear over the solar limb they are called prominences.

Source : NASA
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Aiming for an Open Window

 Why does NASA sometimes schedule a rocket launch for the middle of the night, or aim for a liftoff time when weather is notoriously unlikely to cooperate?

The simplicity of the question belies the complexity of the answer. The best time to start a mission is based on a blend of factors: the flight's target and goals, the needs of the spacecraft, the type of rocket, and the desired trajectory, which refers to the path the vehicle and spacecraft must take to successfully start the mission. Not only do these variables influence the preferred launch time -- the ideal time of departure -- but the overall length of the launch window, which can vary from one second to several hours.

The dynamics change from mission to mission, and determining the launch window is an important part of the overall flight design.
"The interesting thing about our job is each mission is almost completely different from any other mission," said Eric Haddox, the lead flight design engineer in NASA's Launch Services Program (LSP), based at Kennedy Space Center in Florida.

Haddox leads the team of agency and contractor personnel overseeing and integrating the trajectory design efforts of the spacecraft team and launch service contractor for each LSP mission. Once the spacecraft team identifies its needs, a rocket is selected, and the work of hammering out the best launch window and trajectory begins. Ultimately, the launch window and preferred liftoff time are set by the launch service contractor.

"We help everybody understand the requirements of the spacecraft and what the capabilities are of the launch vehicle, and try to mesh the two," Haddox explained.

The most significant deciding factors in when to launch are where the spacecraft is headed, and what its solar needs are. Earth-observing spacecraft, for example, may be sent into low-Earth orbit. Some payloads must arrive at a specific point at a precise time, perhaps to rendezvous with another object or join a constellation of satellites already in place. Missions to the moon or a planet involve aiming for a moving object a long distance away.                                                                                   

For example, NASA's Mars Science Laboratory spacecraft began its eight-month journey to the Red Planet on Nov. 26, 2011 with a launch aboard a United Launch Alliance (ULA) Atlas V rocket from Cape Canaveral Air Force Station in Florida. After the initial push from the powerful Atlas V booster, the Centaur upper stage then sent the spacecraft away from Earth on a specific track to place the laboratory, with its car-sized Curiosity rover, inside Mars' Gale Crater on Aug. 6, 2012. Due to the location of Mars relative to Earth, the prime planetary launch opportunity for the Red Planet occurs only once every 26 months.

Additionally, spacecraft often have solar requirements: they may need sunlight to perform the science necessary to meet the mission's objectives, or they may need to avoid the sun's light in order to look deeper into the dark, distant reaches of space.

Such precision was needed for NASA's Suomi National Polar-orbiting Partnership (NPP) spacecraft, which launched Oct. 28, 2011 aboard a ULA Delta II rocket from Vandenberg Air Force Base in California. The Earth-observing satellite circles at an altitude of 512 miles, sweeping from pole to pole 14 times each day as the planet turns on its axis. A very limited launch window was required so that the spacecraft would cross the ascending node at exactly 1:30 p.m. local time and scan Earth's surface twice each day, always at the same local time.

All of these variables influence a flight's trajectory and launch time. A low-Earth mission with specific timing needs must lift off at the right time to slip into the same orbit as its target; a planetary mission typically has to launch when the trajectory will take it away from Earth and out on the correct course.

According to Haddox, aiming for a specific target -- another planet, a rendezvous point, or even a specific location in Earth orbit where the solar conditions will be just right -- is a bit like skeet shooting.

"You've got this object that's going to go flying out into the air and you've got to shoot it," said Haddox. "You have to be able to judge how far away your target is and how fast it's moving, and make sure you reach the same point at the same time."

But Haddox also emphasized that Earth is rotating on its axis while it orbits the sun, making the launch pad a moving platform. With so many moving players, launch windows and trajectories must be carefully choreographed.

Of course, weather or technical problems can interfere with the team's best plans. Launch windows are intended to absorb small delays while still offering plenty of chances to lift off on a given day. However, launching at a time other than the preferred time could reduce the rocket's performance, potentially limiting the payload mass.

"To launch at any time other than that optimal time, you're going to have to alter the trajectory, steer the rocket to get back to that point," Haddox said. "So that's where it becomes a trade of, 'Okay, if my window were a half hour long, how much performance would I need to fly at any time within a half hour? Or, if my window were an hour long, how much performance would I be able to get out of the rocket to fly at any time within that one hour?'"

Likewise, if a spacecraft has to use any of its onboard propellant to make up for any difference in the trajectory, that could impact the entire mission.

"The more propellant they have, the longer they can do maneuvers or adjust things" during the flight, Haddox explained. "It basically equates to how long they can stay in orbit and do their science."

These potential give-and-take situations are carefully considered during flight planning. Mission managers must find a way to balance the sacrifices while maximizing the chance of getting off the ground.

   Even when the launch and mission teams have chosen the best launch window, they face an additional challenge from the U.S. Air Force: collision avoidance, also called COLA. The U.S. Air Force's 45th Space Wing controls the Eastern Range surrounding Cape Canaveral Air Force Station in Florida; the 30th Space Wing operates the Western Range, including Vandenberg Air Force Base. The range determines whether any orbiting spacecraft or debris could strike the vehicle during its climb to space, and cut out portions of the launch window that are too risky.

Collision avoidance can get tricky, because even though the trajectory has been carefully planned, real-time factors result in some uncertainty. For example, during the trajectory design process, the team assumes certain propellant temperatures. But if the temperatures are slightly different on launch day, that will affect the propellant, which in turn alters the efficiency of the rocket's engines or solid rocket motors.

"The navigation system on the rocket is going to do what it needs to do to get the spacecraft where it needs to be, but it's not going to be the same trajectory you looked at before," said Haddox. "When you've got things that are moving seven to eight kilometers a second, half a second can result in a big distance."

"So it just makes things a lot harder to predict," he added.

On launch day, Haddox and other members of the flight design team are involved in the countdown. Even in the final hours before liftoff, they continue to fine-tune the trajectory analysis based on real-time data collected from weather balloons, ensuring the safety of the rocket and spacecraft as the window opens for another successful mission.

Source : NASA
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Curiosity, The Stunt Double

With a pair of bug-eyes swiveling on a stalk nearly 8 feet off the ground, the 6-wheeled, 1800-lb Mars rover Curiosity doesn't look much like a human being. Yet, right now, the mini-Cooper-sized rover is playing the role of stunt double for NASA astronauts.

"Curiosity is riding to Mars in the belly of a spacecraft, where an astronaut would be," explains Don Hassler of the Southwest Research Institute in Boulder, Colorado. "This means the rover experiences deep-space radiation storms in the same way that a real astronaut would."

Indeed, on Jan. 27th, 2012, Curiosity's spacecraft was hit by the most intense solar radiation storm since 2005. The event began when sunspot AR1402 produced an X2-class solar flare. (On the "Richter Scale of Solar Flares," X-flares are the most powerful kind.) The explosion accelerated a fusillade of protons and electrons to nearly light speed; these subatomic bullets were guided by the sun's magnetic field almost directly toward Curiosity.

When the particles hit the outer walls of the spacecraft, they shattered other atoms and molecules in their path, producing a secondary spray of radiation that Curiosity both absorbed and measured.

When the particles hit the outer walls of the spacecraft, they shattered other atoms and molecules in their path, producing a secondary spray of radiation that Curiosity both absorbed and measured.

"Curiosity was in no danger," says Hassler. "In fact, we intended all along for the rover to experience these storms en route to Mars."
Unlike previous Mars rovers, Curiosity is equipped with a Radiation Assessment Detector. The instrument, nicknamed "RAD," counts cosmic rays, neutrons, protons and other particles over a wide range of biologically-interesting energies. RAD's prime mission is to investigate the radiation environment on the surface of Mars, but researchers have turned it on early so that it can also probe the radiation environment on the way to Mars as well.

Curiosity's location inside the spacecraft is key to the experiment.

"We have a pretty good idea what the radiation environment is like outside," says Hassler, who is the principal investigator for RAD. "Inside the spacecraft, however, is still a mystery."

Even supercomputers have trouble calculating exactly what happens when high-energy cosmic rays and solar energetic particles hit the walls of a spacecraft. One particle hits another; fragments fly; the fragments themselves crash into other molecules.

"It's very complicated. Curiosity is giving us a chance to actually measure what happens."

Even when the sun is quiet, Curiosity is bombarded by a slow drizzle of cosmic rays—high-energy particles accelerated by distant black holes and supernova explosions. In the aftermath of the Jan. 27th X-flare, RAD detected a surge of particles several times more numerous than the usual cosmic ray counts. Hassler's team is still analyzing the data to understand what it is telling them about the response of the spacecraft to the storm.

More X-flares will help by adding to the data set. Hassler expects the sun to cooperate, because the solar cycle is trending upward toward a maximum expected in early 2013.

As of February 2012, "we still have 6 months to go before we reach Mars. That's plenty of time for more solar storms."

A stunt double's work is never done.
Source : NASA
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NASA's Spitzer Finds Solid Buckyballs in Space

Astronomers using data from NASA's Spitzer Space Telescope have, for the first time, discovered buckyballs in a solid form in space. Prior to this discovery, the microscopic carbon spheres had been found only in gas form in the cosmos.
Formally named buckminsterfullerene, buckyballs are named after their resemblance to the late architect Buckminster Fuller's geodesic domes. They are made up of 60 carbon atoms arranged into a hollow sphere, like a soccer ball. Their unusual structure makes them ideal candidates for electrical and chemical applications on Earth, including superconducting materials, medicines, water purification and armor.
In the latest discovery, scientists using Spitzer detected tiny specks of matter, or particles, consisting of stacked buckyballs. They found the particles around a pair of stars called "XX Ophiuchi," 6,500 light-years from Earth, and detected enough to fill the equivalent in volume to 10,000 Mount Everests.

"These buckyballs are stacked together to form a solid, like oranges in a crate," said Nye Evans of Keele University in England, lead author of a paper appearing in the Monthly Notices of the Royal Astronomical Society. "The particles we detected are minuscule, far smaller than the width of a hair, but each one would contain stacks of millions of buckyballs."
Buckyballs were detected definitively in space for the first time by Spitzer in 2010. Spitzer later identified the molecules in a host of different cosmic environments. It even found them in staggering quantities, the equivalent in mass to 15 Earth moons, in a nearby galaxy called the Small Magellanic Cloud.
In all of those cases, the molecules were in the form of gas. The recent discovery of buckyballs particles means that large quantities of these molecules must be present in some stellar environments in order to link up and form solid particles. The research team was able to identify the solid form of buckyballs in the Spitzer data because they emit light in a unique way that differs from the gaseous form.

"This exciting result suggests that buckyballs are even more widespread in space than the earlier Spitzer results showed," said Mike Werner, project scientist for Spitzer at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "They may be an important form of carbon, an essential building block for life, throughout the cosmos."
Buckyballs have been found on Earth in various forms. They form as a gas from burning candles and exist as solids in certain types of rock, such as the mineral shungite found in Russia, and fulgurite, a glassy rock from Colorado that forms when lightning strikes the ground. In a test tube, the solids take on the form of dark, brown "goo."
"The window Spitzer provides into the infrared universe has revealed beautiful structure on a cosmic scale," said Bill Danchi, Spitzer program scientist at NASA Headquarters in Washington. "In yet another surprise discovery from the mission, we're lucky enough to see elegant structure at one of the smallest scales, teaching us about the internal architecture of existence."

Source : NASA
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Hubble Reveals a New Class of Extrasolar Planet

An international team of astronomers led by Zachory Berta of the Harvard-Smithsonian Center for Astrophysics (CfA) made the observations of the planet GJ 1214b.

“GJ 1214b is like no planet we know of,” Berta said. “A huge fraction of its mass is made up of water.”

The ground-based MEarth Project, led by CfA’s David Charbonneau, discovered GJ 1214b in 2009. This super-Earth is about 2.7 times Earth’s diameter and weighs almost seven times as much. It orbits a red-dwarf star every 38 hours at a distance of 2 million kilometres, giving it an estimated temperature of 230 degrees Celsius.

In 2010, CfA scientist Jacob Bean and colleagues reported that they had measured the atmosphere of GJ 1214b, finding it likely that it was composed mainly of water. However, their observations could also be explained by the presence of a planet-enshrouding haze in GJ 1214b’s atmosphere.

Berta and his co-authors, who include Derek Homeier of ENS Lyon, France, used Hubble’s Wide Field Camera 3 (WFC3) to study GJ 1214b when it crossed in front of its host star. During such a transit, the star’s light is filtered through the planet’s atmosphere, giving clues to the mix of gases.

“We’re using Hubble to measure the infrared colour of sunset on this world,” Berta explained.
Hazes are more transparent to infrared light than to visible light, so the Hubble observations help to tell the difference between a steamy and a hazy atmosphere.
They found the spectrum of GJ 1214b to be featureless over a wide range of wavelengths, or colours. The atmospheric model most consistent with the Hubble data is a dense atmosphere of water vapour.
“The Hubble measurements really tip the balance in favour of a steamy atmosphere,” Berta said.
Since the planet’s mass and size are known, astronomers can calculate the density, of only about 2 grams per cubic centimetre. Water has a density of 1 gram per cubic centimetre, while Earth’s average density is 5.5 grams per cubic centimetre. This suggests that GJ 1214b has much more water than Earth does, and much less rock.

As a result, the internal structure of GJ 1214b would be extraordinarily different from that of our world.
“The high temperatures and high pressures would form exotic materials like ‘hot ice’ or ‘superfluid water’, substances that are completely alien to our everyday experience,” Berta said.
Theorists expect that GJ 1214b formed further out from its star, where water ice was plentiful, and migrated inward early in the system’s history. In the process, it would have passed through the star’s habitable zone, where surface temperatures would be similar to Earth’s. How long it lingered there is unknown.
GJ 1214b is located in the constellation of Ophiuchus (The Serpent Bearer), and just 40 light-years from Earth. Therefore, it’s a prime candidate for study by the NASA/ESA/CSA James Webb Space Telescope, planned for launch later this decade.
A paper reporting these results has been accepted for publication in the Astrophysical Journal and is available online.

Source : NASA
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NASA's Chandra Finds Fastest Wind From Stellar-Mass Black Hole

Astronomers using NASA's Chandra X-ray Observatory have clocked the fastest wind yet discovered blowing off a disk around a stellar-mass black hole. This result has important implications for understanding how this type of black hole behaves.

The record-breaking wind is moving about 20 million mph, or about 3 percent of the speed of light. This is nearly 10 times faster than had ever been seen from a stellar-mass black hole.

Stellar-mass black holes are born when extremely massive stars collapse. They typically weigh between five and 10 times the mass of the sun. The stellar-mass black hole powering this super wind is known as IGR J17091-3624, or IGR J17091 for short.

"This is like the cosmic equivalent of winds from a category five hurricane," said Ashley King from the University of Michigan, lead author of the study published in the Feb. 20 issue of The Astrophysical Journal Letters. "We weren't expecting to see such powerful winds from a black hole like this."

The wind speed in IGR J17091 matches some of the fastest winds generated by supermassive black holes, objects millions or billions of times more massive.

"It's a surprise this small black hole is able to muster the wind speeds we typically only see in the giant black holes," said co-author Jon M. Miller, also from the University of Michigan. "In other words, this black hole is performing well above its weight class."

Another unanticipated finding is that the wind, which comes from a disk of gas surrounding the black hole, may be carrying away more material than the black hole is capturing.

"Contrary to the popular perception of black holes pulling in all of the material that gets close, we estimate up to 95 percent of the matter in the disk around IGR J17091 is expelled by the wind," King said.

Unlike winds from hurricanes on Earth, the wind from IGR J17091 is blowing in many different directions. This pattern also distinguishes it from a jet, where material flows in highly focused beams perpendicular to the disk, often at nearly the speed of light.

Simultaneous observations made with the National Radio Astronomy Observatory's Expanded Very Large Array showed a radio jet from the black hole was not present when the ultra-fast wind was seen, although a radio jet is seen at other times. This agrees with observations of other stellar-mass black holes, providing further evidence the production of winds can stifle jets.

The high speed for the wind was estimated from a spectrum made by Chandra in 2011. Ions emit and absorb distinct features in spectra, which allow scientists to monitor them and their behavior. A Chandra spectrum of iron ions made two months earlier showed no evidence of the high-speed wind, meaning the wind likely turns on and off over time.

Astronomers believe that magnetic fields in the disks of black holes are responsible for producing both winds and jets. The geometry of the magnetic fields and rate at which material falls towards the black hole must influence whether jets or winds are produced.

IGR J17091 is a binary system in which a sun-like star orbits the black hole. It is found in the bulge of the Milky Way galaxy, about 28,000 light years away from Earth. 

Source : NASA 

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Preps Continue for Launching Engine Icing Research

NASA scientists are making progress in their preparations to mount a detailed research campaign aimed at solving a modern-day aviation mystery involving the unlikely combination of fire and ice inside a running jet engine.

The investigation deals with the seemingly strange notion that ice crystals associated with warm-weather storms can be ingested into the core of a jet engine, melt and then re-freeze, potentially causing the engine to lose power or shut down altogether. Safety officials have documented more than 150 incidents of this phenomenon since 1988. Most of the incidents have occurred in the tropics.

It doesn’t seem intuitive that ice can form in the core of a warm engine,” said Ron Colantonio, manager of the Atmospheric Environment Safety Technologies Project at NASA’s Glenn Research Center in Cleveland.

So in order to make sense of the mystery, NASA and its research partners are planning to gather information by flying a specially-outfitted business jet in high-altitude, warm-weather conditions suspected of having a large amount of ice crystals.

Technicians in California are currently modifying a Gulfstream G2 airplane to hold a suite of meteorological instruments, with hopes of having everything ready for initial trial runs of the full setup in Florida this August.

The research team then will take the lessons learned from their trial runs, make appropriate changes and prepare for the primary campaign, which is now targeted between January and March, 2013. These flights will take place over Darwin, Australia, an area known for having the type of storms that include high levels of ice crystals.

                                                                                    

Meanwhile, another set of investigators will be preparing the ground segment of the research, which involves simulating the engine icing conditions in an engine test facility at Glenn, as well as refining new computer codes to help predict where and when the engine icing conditions exist.

For now, pilots are being trained to recognize the potential existence of these ice crystals, which are about the same size as baking soda, and advised to avoid the weather conditions as best they can. Although a potential hazard, no accident has been attributed to the phenomenon in the 23 years since it was identified.


For now, pilots are being trained to recognize the potential existence of these ice crystals, which are about the same size as baking soda, and advised to avoid the weather conditions as best they can. Although a potential hazard, no accident has been attributed to the phenomenon in the 23 years since it was identified.

                                                                                                                                                                                    

                                                                                 

 In most of the known cases, pilots have managed to restore engine power and reach their destinations without further problems. According to the Federal Aviation Administration, there have been two forced landings.

For example, in 2005, both engines of a Beechcraft business jet failed at 38,000 feet above Jacksonville, Fla. The pilot safely glided the aircraft to an airport, dodging thunderstorms and ominous clouds on the way down.


It is expected that updated flight safety rules and engine testing standards will be adopted once all the research is compiled and analyzed during the next few years.

Source : NASA

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Planck All-Sky Images Show Cold Gas and Strange Haze

New images from the Planck mission show previously undiscovered islands of star formation and a mysterious haze of microwave emissions in our Milky Way galaxy. The views give scientists new treasures to mine and take them closer to understanding the secrets of our galaxy.

Planck is a European Space Agency mission with significant NASA participation.
"The images reveal two exciting aspects of the galaxy in which we live," said Planck scientist Krzysztof M. Gorski from NASA's Jet Propulsion Laboratory in Pasadena, Calif., and Warsaw University Observatory in Poland. "They show a haze around the center of the galaxy, and cold gas where we never saw it before."
The new images show the entire sky, dominated by the murky band of our Milky Way galaxy. One of them shows the unexplained haze of microwave light previously hinted at in measurements by NASA's Wilkinson Microwave Anisotropy Probe (WMAP).

"The haze comes from the region surrounding the center of our galaxy and looks like a form of light energy produced when electrons accelerate through magnetic fields," said Davide Pietrobon, another JPL Planck scientist.

"We're puzzled though, because this haze is brighter at shorter wavelengths than similar light emitted elsewhere in the galaxy," added Gorski.
Several explanations have been proposed for this unusual behaviour.

"Theories include higher numbers of supernovae, galactic winds and even the annihilation of dark-matter particles," said Greg Dobler, a Planck collaborator from the University of California in Santa Barbara, Calif. Dark matter makes up about a quarter of our universe, but scientists don't know exactly what it is.

The second all-sky image is the first map to show carbon monoxide over the whole sky. Cold clouds with forming stars are predominantly made of hydrogen molecules, difficult to detect because they do not readily emit radiation. Carbon monoxide forms under similar conditions, and though it is rarer, the gas emits more light. Astronomers can use carbon monoxide to identify the clouds of hydrogen where stars are born.
Surveys of carbon monoxide undertaken with radio telescopes on the ground are time-consuming, so they are limited to portions of the sky where clouds of molecules are already known or expected to exist. Planck scans the whole sky, allowing astronomers to detect the gas where they weren't expecting to find it.

Planck's primary goal is to observe the Cosmic Microwave Background, the relic radiation from the Big Bang, and to extract its encoded information about what our universe is made of, and the origin of its structure.
This relic radiation can only be reached once all sources of foreground emission, such as the galactic haze and the carbon monoxide signals, have been identified and removed.
"The lengthy and delicate task of foreground removal provides us with prime datasets that are shedding new light on hot topics in galactic and extragalactic astronomy alike," said Jan Tauber, Planck project scientist at the European Space Agency.
Planck's first findings on the Big Bang's relic radiation are expected to be released in 2013. The new results are being presented this week at an international astronomy conference in Bologna, Italy.

Source : NASA
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Spacecraft Computer Issue Resolved

Mars Science Laboratory Mission Status Report

Engineers have found the root cause of a computer reset that occurred two months ago on NASA's Mars Science Laboratory and have determined how to correct it.
The fix involves changing how certain unused data-holding locations, called registers, are configured in the memory management of the type of computer chip used on the spacecraft. Billions of runs on a test computer with the modified register configuration yielded no repeat of the reset behavior. The mission team made this software change on the spacecraft's computer last week and confirmed this week that the update is successful.

The reset occurred Nov. 29, 2011, three days after launch, during use of the craft's star scanner. The cause has been identified as a previously unknown design idiosyncrasy in the memory management unit of the Mars Science Laboratory computer processor. In rare sets of circumstances unique to how this mission uses the processor, cache access errors could occur, resulting in instructions not being executed properly. This is what happened on the spacecraft on Nov. 29.
"Good detective work on understanding why the reset occurred has yielded a way to prevent it from occurring again," said Mars Science Laboratory Deputy Project Manager Richard Cook of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "The successful resolution of this problem was the outcome of productive teamwork by engineers at the computer manufacturer and JPL."
The Mars-bound spacecraft performed a brief alignment activity using its star scanner and sun sensor on Jan. 26. During the alignment observations, the star scanner detected Mars.
"Our target is in view," said JPL's Steve Collins, attitude control subsystem engineer for Mars Science Laboratory's cruise from Earth to Mars.
The spacecraft began normal use of its star tracker and true celestial navigation this week after its software update.
The Mars Science Laboratory mission will use its car-size rover, Curiosity, to investigate whether the selected region on Mars inside Gale Crater has offered environmental conditions favorable for supporting microbial life and favorable for preserving clues about whether life existed. Curiosity will land on Mars on Aug. 6, 2012, Universal Time and Eastern Daylight Time (evening of Aug. 5, Pacific Daylight Time).
The spacecraft's cruise-stage solar array is producing 704 watts. The telecommunications rates are 1 kilobit per second for uplink and 800 bits per second for downlink. The spacecraft is spinning at 1.97 rotations per minute.
As of 9 a.m. PST (noon EST, or 1700 Universal Time) on Friday, Feb. 10, the spacecraft will have traveled 127 million miles (205 million kilometers) of its 352-million-mile (567-million-kilometer) flight to Mars. It will be moving at about 17,800 miles per hour (28,600 kilometers per hour) relative to Earth and at about 63,700 mph (102,500 kilometers per hour) relative to the sun.

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Source : NASA

Hubble Zooms in on a Magnified Galaxy

Thanks to the presence of a natural "zoom lens" in space, NASA's Hubble Space Telescope got a uniquely close-up look at the brightest "magnified" galaxy yet discovered.

This observation provides a unique opportunity to study the physical properties of a galaxy vigorously forming stars when the universe was only one-third its present age.
A so-called gravitational lens is produced when space is warped by a massive foreground object, whether it is the sun, a black hole or an entire cluster of galaxies. The light from more-distant background objects is distorted, brightened and magnified as it passes through this gravitationally disturbed region.

A team of astronomers led by Jane Rigby of NASA's Goddard Space Flight Center in Greenbelt, Md., aimed Hubble at one of the most striking examples of gravitational lensing, a nearly 90-degree arc of light in the galaxy cluster RCS2 032727-132623. Hubble's view of the distant background galaxy is significantly more detailed than could ever be achieved without the help of the gravitational lens.

The results have been accepted for publication in the Astrophysical Journal, in a paper led by Keren Sharon of the Kavli Institute for Cosmological Physics at the University of Chicago. Professor Michael Gladders and graduate student Eva Wuyts of the University of Chicago were also key team members.

The presence of the lens helps show how galaxies evolved from 10 billion years ago to today. While nearby galaxies are fully mature and are at the tail end of their star-formation histories, distant galaxies tell us about the universe's formative years. The light from those early events is just now arriving at Earth. Very distant galaxies are not only faint but also appear small on the sky. Astronomers would like to see how star formation progressed deep within these galaxies. Such details would be beyond the reach of Hubble's vision were it not for the magnification made possible by gravity in the intervening lens region.

In 2006 a team of astronomers using the Very Large Telescope in Chile measured the arc's distance and calculated that the galaxy appears more than three times brighter than previously discovered lensed galaxies. In 2011 astronomers used Hubble to image and analyze the lensed galaxy with the observatory's Wide Field Camera 3.

The distorted image of the galaxy is repeated several times in the foreground lensing cluster, as is typical of gravitational lenses. The challenge for astronomers was to reconstruct what the galaxy really looked like, were it not distorted by the cluster's funhouse-mirror effect.

Hubble's sharp vision allowed astronomers to remove the distortions and reconstruct the galaxy image as it would normally look. The reconstruction revealed regions of star formation glowing like bright Christmas tree bulbs. These are much brighter than any star-formation region in our Milky Way galaxy.

Through spectroscopy, the spreading out of the light into its constituent colors, the team plans to analyze these star-forming regions from the inside out to better understand why they are forming so many stars.

Source : NASA

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