Massive Black Hole Implicated in Stellar Destruction

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Composite image of a so-called ultraluminous X-ray source, or ULXNew results from NASA's Chandra X-ray Observatory and the Magellan telescopes suggest that a dense stellar remnant has been ripped apart by a black hole a thousand times as massive as the Sun. If confirmed, this discovery would be a cosmic double play: it would be strong evidence for an intermediate mass black hole, which has been a hotly debated topic, and would mark the first time such a black hole has been caught tearing a star apart.

This scenario is based on Chandra observations, which revealed an unusually luminous source of X-rays in a dense cluster of old stars, and optical observations that showed a peculiar mix of elements associated with the X-ray emission. Taken together, a case can be made that the X-ray emission is produced by debris from a disrupted white dwarf star that is heated as it falls towards a massive black hole. The optical emission comes from debris further out that is illuminated by these X-rays.

The intensity of the X-ray emission places the source in the "ultraluminous X-ray source" or ULX category, meaning that it is more luminous than any known stellar X-ray source, but less luminous than the bright X-ray sources (active galactic nuclei) associated with supermassive black holes in the nuclei of galaxies. The nature of ULXs is a mystery, but one suggestion is that some ULXs are black holes with masses between about a hundred and several thousand times that of the Sun, a range intermediate between stellar-mass black holes and supermassive black holes located in the nuclei of galaxies.

This ULX is in a globular cluster, a very old and crowded conglomeration of stars. Astronomers have suspected that globular clusters could contain intermediate-mass black holes, but conclusive evidence for this has been elusive.

"Astronomers have made cases for stars being torn apart by supermassive black holes in the centers of galaxies before, but this is the first good evidence for such an event in a globular cluster," said Jimmy Irwin of the University of Alabama who led the study.

Irwin and his colleagues obtained optical spectra of the object using the Magellan I and II telescopes in Las Campanas, Chile. These data reveal emission from gas rich in oxygen and nitrogen but no hydrogen, a rare set of signals from globular clusters. The physical conditions deduced from the spectra suggest that the gas is orbiting a black hole of at least 1,000 solar masses. The abundant amount of oxygen and absence of hydrogen indicate that the destroyed star was a white dwarf, the end phase of a solar-type star that has burned its hydrogen leaving a high concentration of oxygen. The nitrogen seen in the optical spectrum remains an enigma.

"We think these unusual signatures can be explained by a white dwarf that strayed too close to a black hole and was torn apart by the extreme tidal forces," said coauthor Joel Bregman of the University of Michigan.

Theoretical work suggests that the tidal disruption-induced X-ray emission could stay bright for more than a century, but it should fade with time. So far, the team has observed there has been a 35 percent in X-ray emission from 2000 to 2008.

The ULX in this study is located in NGC 1399, an elliptical galaxy about 65 million light years from Earth.

Irwin presented these results at the 215th meeting of the American Astronomical Society in Washington, DC. NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.

More information, including images and other multimedia, can be found at:

 http://chandra.harvard.edu

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Opearions of Heat Exchanger Unit

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Hi guys, we have just installed a heat exchanger unit on one of our ruthenium distillation processes to cool down the vapour coming out of a 100^oC reactor temperature. The cooiling water used is at 18^oC-23^oC. The unit (HE) that was used is HEC450 which can withstand temperature difference of 95^o

Wiring, Safety Work Earn Chemist Top Accolades

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Tracy Gibson of ASRC Aerospace Corp. works in the Space Life Sciences Lab at NASA's Kennedy Space CenterYou may not know who Tracy Gibson is, but one day you might ride on an airplane he has made safer.

Gibson is a senior principal investigator for ASRC Aerospace Corp.'s work at NASA's Kennedy Space Center. The invention he hopes will revolutionize spaceflight and air travel is self-healing wiring. If he and his team of researchers can perfect the right compound, odds are a lot of people, from astronauts and pilots to aircraft passengers, will have him to thank for preventing a potentially catastrophic short circuit.

Because the wiring repair field is so fresh, many approaches are being examined. Some designs embed tiny capsules inside wiring insulation. When the insulation rips open or tears, the capsules break and the material inside oozes out and then hardens to close the gap. But that method won't likely work for aerospace applications because spacecraft and airplanes require flexible wiring, Gibson said.

He is searching basically for a compound that pulls itself back together after a tear.

Gibson's research into that burgeoning field and his scientific work on other projects has been recognized with Kennedy's first Engineer/Scientist of the Year award for contractor employees. Gibson's other projects range from a chemical analyzer that can fit on a rover to refining hazardous materials detectors. NASA's Bob Youngquist earned the honor for the agency's researchers at Kennedy.

Scientists here note that research at Kennedy is expected to produce a tangible product that can be applied to a spacecraft, ground support equipment or another aspect of launch, processing or operations. For Gibson, the payoff of applying his work is one of the many rewards of his post.

"I feel pretty privileged with the work I get to do and at the end you get to see how it might impact the future of space and aerospace," he said. "It's exciting work, it keeps me on my toes. I'm not sure I could ask for anything more."

Gibson and his team spend considerable time in labs at Kennedy, whether at the Space Life Sciences Laboratory or inside the Operations and Checkout Building's facilities. Sometimes, the field work takes him far off-center.

For example, his team took a trip to Hawaii last year to evaluate a very small mechanism that could analyze moon dust looking for signs of chemicals which could be turned into water or used as rocket fuel for astronauts living on the moon.

Gibson praises the team approach employed at Kennedy, saying there aren't many trouble spots his group isn't willing to delve into.

"What I view our group as is problem solvers," Gibson said. "We've got very talented folks here at Kennedy. We can sit and brainstorm and overcome the problem."

At 39, Gibson has plenty more time for research and development. Even if he doesn't revolutionize wiring, he and his team are gaining expertise in a variety of areas that he thinks will pay off for the agency and public at some point.

"I just hope that by the time my career ends, I will have developed technologies that will have been utilized by NASA or by some industrial use that's made a difference," Gibson said. "I just would like to know that I've worked hard at what I've done and I've helped push technology forward."

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Moon Rock Gains Traveling Companion for Historic Return to Space

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A moon rock collected during the historic Apollo 11 mission more than 40 years ago will be heading back to space and a new home aboard the International Space Station, sharing quarters with a piece of Mt. Everest.

On May 20, 2009, former NASA astronaut Scott Parazynski carried the rock to the top of Mt. Everest where he collected a rock from the world's highest mountain to accompany the lunar sample for its return to space.

During an event Jan. 6 at Space Center Houston, Parazynski will present both rocks to NASA astronaut and STS-130 mission Commander George Zamka. Zamka will deliver the rocks to the space station during space shuttle Endeavour's mission next month.

Collected from the Sea of Tranquility on the lunar surface, the moon rock and its Mt. Everest companion will be displayed inside the station's Tranquility module, which the STS-130 crew will deliver to the station.

During the presentation, Parazynski will share the story of his journey to the top of the world and what inspired him to carry along the lunar sample, followed by an audience question and answer session. The event is scheduled from 11 a.m. to noon CST in the Blast Off Theater in the Mission Status Center at Space Center Houston. NASA Television will air a recording of the event at 3:30 p.m.

Parazynski and Zamka will be available for interviews from noon to 12:30 p.m. Reporters interested in attending should contact Victor Scott at 281-483-4942 or via e-mail at:

victor.j.scott@nasa.gov

Updates, photos and videos during the presentation will be posted on NASA's Johnson Space Center Twitter feed and can be followed using the hashtag #moon_everest. From 12:30 to 1 p.m., Parazynski will answer questions live via Twitter. To follow Johnson on Twitter, visit:

http://www.twitter.com/NASA_Johnson

For information about NASA and agency programs, visit:

http://www.nasa.gov

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Temperature Rise Test

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I tested temperature rise of 16 kva single phase copper wound(wound core) transformer whose temperature rise was greater than 35 deg.cent. it was about 41 deg cent.plz suggest me what are the reasons by which transformer fails in temperature rise test?

NASA’s Kepler Space Telescope Discovers its First Five Exoplanets

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This artists concept shows a cloudy Jupiter-like planet that orbits very close to its fiery hot star.

NASA's Kepler space telescope, designed to find Earth-size planets in the habitable zone of sun-like stars, has discovered its first five new exoplanets, or planets beyond our solar system.

Kepler's high sensitivity to both small and large planets enabled the discovery of the exoplanets, named Kepler 4b, 5b, 6b, 7b and 8b. The discoveries were announced Monday, Jan. 4, by the members of the Kepler science team during a news briefing at the American Astronomical Society meeting in Washington.

"These observations contribute to our understanding of how planetary systems form and evolve from the gas and dust disks that give rise to both the stars and their planets," said William Borucki of NASA's Ames Research Center in Moffett Field, Calif. Borucki is the mission's science principal investigator. "The discoveries also show that our science instrument is working well. Indications are that Kepler will meet all its science goals."

Known as "hot Jupiters" because of their high masses and extreme temperatures, the new exoplanets range in size from similar to Neptune to larger than Jupiter. They have orbits ranging from 3.3 to 4.9 days. Estimated temperatures of the planets range from 2,200 to 3,000 degrees Fahrenheit, hotter than molten lava and much too hot for life as we know it. All five of the exoplanets orbit stars hotter and larger than Earth's sun.

"It's gratifying to see the first Kepler discoveries rolling off the assembly line," said Jon Morse, director of the Astrophysics Division at NASA Headquarters in Washington. "We expected Jupiter-size planets in short orbits to be the first planets Kepler could detect. It's only a matter of time before more Kepler observations lead to smaller planets with longer period orbits, coming closer and closer to the discovery of the first Earth analog."

Launched on March 6, 2009, from Cape Canaveral Air Force Station in Florida, the Kepler mission continuously and simultaneously observes more than 150,000 stars. Kepler's science instrument, or photometer, already has measured hundreds of possible planet signatures that are being analyzed.

While many of these signatures are likely to be something other than a planet, such as small stars orbiting larger stars, ground-based observatories have confirmed the existence of the five exoplanets. The discoveries are based on approximately six weeks' worth of data collected since science operations began on May 12, 2009.

Kepler looks for the signatures of planets by measuring dips in the brightness of stars. When planets cross in front of, or transit, their stars as seen from Earth, they periodically block the starlight. The size of the planet can be derived from the size of the dip. The temperature can be estimated from the characteristics of the star it orbits and the planet's orbital period.

Planet Size

Kepler will continue science operations until at least November 2012. It will search for planets as small as Earth, including those that orbit stars in a warm habitable zone where liquid water could exist on the surface of the planet. Since transits of planets in the habitable zone of solar-like stars occur about once a year and require three transits for verification, it is expected to take at least three years to locate and verify an Earth-size planet.

According to Borucki, Kepler's continuous and long-duration search should greatly improve scientists' ability to determine the distributions of planet size and orbital period in the future. "Today's discoveries are a significant contribution to that goal," Borucki said. "The Kepler observations will tell us whether there are many stars with planets that could harbor life, or whether we might be alone in our galaxy."

Kepler is NASA's 10th Discovery mission. Ames is responsible for the ground system development, mission operations and science data analysis. NASA's Jet Propulsion Laboratory in Pasadena, Calif., managed the Kepler mission development. Ball Aerospace & Technologies Corp. of Boulder, Colo., was responsible for developing the Kepler flight system. Ball and the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder are supporting mission operations.

Ground observations necessary to confirm the discoveries were conducted with ground-based telescopes the Keck I in Hawaii; Hobby-Ebberly and Harlan J. Smith 2.7m in Texas; Hale and Shane in California; WIYN, MMT and Tillinghast in Arizona; and Nordic Optical in the Canary Islands, Spain.

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NASA Astronaut John Grunsfeld, Instrumental to Hubble Telescope Repair, Will Help Oversee its Science Operations

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Astronaut John Grunsfeld, attired in his Extravehicular Mobility Unit (EMU) spacesuit, is pictured in the Earth-orbiting Space Shuttle Atlantis' airlock as he prepares for the STS-125 mission's fifth and final session of extravehicular activity
NASA astronaut John Grunsfeld, who participated in three spaceflights to service the Hubble Space Telescope, is leaving the agency to become the deputy director of the Space Telescope Science Institute in Baltimore. The institute is the science operations center for Hubble and the James Webb Space Telescope, which is planned for launch in 2014.

"During the past 18 years, John has been a true asset to the agency," said NASA Administrator Charles Bolden, a former astronaut who few on the STS-31 mission that deployed the Hubble. "Some have called him the chief Hubble repairman, but I call him a friend and wish him the best in his new endeavor."

In addition to Grunsfeld's flights to Hubble (STS-103 in Dec. 1999, STS-109 in March 2002, and STS-125 in May 2009), he also served on two other shuttle missions. He performed eight critical spacewalks and logged more than 835 hours in space.

During 2003 and 2004, he was NASA's Chief Scientist at the agency's headquarters in Washington. He helped develop the Vision for Space Exploration, which set NASA on the path for future exploration endeavors.

In accepting the institute position, Grunsfeld said, "This is an incredibly exciting opportunity for me to work at a focal point of top astronomers at the leading edge of scientific inquiry. The team at the Space Telescope Science Institute has a demonstrated record of meeting the high performance challenges of operating the Hubble Space Telescope and preparing for the James Webb Space Telescope. I look forward to working with this excellent team as we continue to explore the mysteries of the universe."

Related Site:

› John Grunsfeld's Official Biography
› Hubble Space Telescope Mission Section

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I Actually Need the PowerPost to Be Real [Concept]

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Lately I've been sharing my desk. Lots of fun, but you quickly end up with a cable mess and running out of plugs. That's why I want someone to convert the RedDot Award-winner PowerPost into a real product.

It's a simple concept: An alternative table leg that is in itself a huge power strip. My only worry is that, knowing myself, it would look looking like a deranged hydra shortly after its installation. [Red Dot Award]



Concrete Slab Questions–Revisited

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A few weeks ago I posted a question about the load bearing capacity of a slab floor on a bldg. I'm considering using as a warehouse. Thanks to prompting of this forum, I actually found the blueprints for the building (1920!)

The rebar configuration is called Spiral Mushroom Reiforcement--bas

Centrifugal Gas Compressor

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does any one know a manufacturing company for Centrifugal gas compreesor, two satges. First stage with flow rate of 100mmSCFD & the second stage is with flow rate of 150mmSCFD. I contacted Dresser Rand, Rolls Royce, GE-Nuovo Pignone , Solar Turbine, and Elliot. All of them have declined except S

Acid proof hard floor

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I am working for a lead acid battery industry. In my factory floor due to electrolyte (diluted sulfuric acid) spillage and 2500 kg loaded hand pallet-truck movement floor eroding is inevitable. I have already tried floor epoxy, tiles and asphalt but failed due to loaded pallet-truck and feet of the

3 Basic Steps to Avoid Joining a Botnet

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Banging the drum for security awareness never gets old. As much as CSOs try to get folks to bone up on safe practices (both online and in the office), there are always going to be some who need reminding.

Online, the biggest battle these days is against botnets: networks of infected computers w

determination

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what is determination on wall thickness of pipe vs rating?

any standard refer to this.

e.g: wall thk (< Sch.40) can only stand up to 150# rating.

electrostatic type air cleaner needed.

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Is there any way to cheaply make an electrostatic air cleaner, other than placing 2 television screens a few inches apart and blowing air through them? My wife is going nuts in our house. We have decent air filters in the central air unit, which is not running right now anyway, due to my use of a bi