Our Galactic Twin

What would our Milky Way galaxy look like if we could travel outside it and snap a picture? It might look a lot like a new image by NASA’s Spitzer Space Telescope of a spiral galaxy called NGC 7331 – a virtual twin of our Milky Way.

The picture, which can be viewed at http://photojournal.jpl.nasa.gov/catalog/PIA06322 , shows our twin as never before. Its swirling arms spin outward from a central bulge of light, which is outlined by a ring of actively forming stars.

“Being inside our galaxy makes it difficult to see what’s going on in the center,” said Dr. J.D. Smith, a member of the team that observed NGC 7331, and an astronomer at the University of Arizona, Tucson. “By looking at a very similar galaxy, we gain a bird’s eye-view of what the entire Milky Way might look like.”

Such an outside perspective will teach astronomers how our own galaxy, as well as others like it, might have formed and evolved.

The latest observations are the first in a large-scale effort to observe 75 nearby galaxies with Spitzer’s highly sensitive infrared eyes. Called Spitzer Infrared Nearby Galaxies Survey, the program will combine Spitzer data with that from other ground- and space-based telescopes operating at wavelengths ranging from ultraviolet to radio to create a comprehensive map of the selected galaxies.

The program’s first target, NGC 7331, was chosen in part for its striking similarities to the Milky Way. While these so-called twin galaxies do not share the same parents, they have many features in common, including number of stars, mass, spiral arm pattern and star-formation rate of a few stars per year. Whether the Milky Way has an inner star-forming ring like that of NGC 7331 is not known. NGC 7331 is located about 50 million light-years away in the constellation Pegasus.

The new Spitzer image demonstrates the power of the telescope’s infrared eyes to dissect galaxies into their various parts. Taken by the telescope’s infrared array camera, the false-colored picture readily distinguishes NGC 7331’s arms (brownish red), central bulge (blue) and star-forming ring (yellow). The composition of materials making up these regions was also revealed by the Spitzer observations: the central bulge consists primarily of older stars; the ring possesses a large amount of gas and dusty organic molecules called polycyclic aromatic hydrocarbons, which typically glow when illuminated by newborn stars; and the arms contain these same dust grains to a lesser degree. Polycyclic aromatic hydrocarbons are also found on Earth, on burnt toast and in car exhaust among other places.

Data from Spitzer’s infrared spectrograph instrument were also used to show that the center of NGC 7331 harbors either an unusually high concentration of massive stars, or a moderately active black hole about the same size as the one lurking at the core of our galaxy.

These findings will appear in two papers in the September issue of a special supplement to the Astrophysical Journal. Dr. Michael W. Regan of the Space Telescope Institute, Baltimore, Md., is lead author of a paper detailing observations from the infrared array camera, and Smith is lead author of a paper on the infrared spectrograph results. The Spitzer Infrared Nearby Galaxies Survey project is conducted by a team of about 25 scientists from 12 institutions, and is led by principal investigator Dr. Robert C. Kennicutt of the University of Arizona, Tucson.

Launched August 25, 2003, the Spitzer Space Telescope is the fourth of NASA’s Great Observatories, a program that also includes the Hubble Space Telescope, Chandra X-ray Observatory and Compton Gamma Ray Observatory.

JPL manages the Spitzer Space Telescope mission for NASA’s Office of Space Science, Washington, D.C. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. JPL is a division of Caltech. Spitzer’s infrared spectrograph was built by Cornell University, Ithaca, N.Y., and Ball Aerospace Corporation, Boulder, Colo. The instrument’s development was led by Dr. Jim Houck of Cornell. Spitzer’s infrared array camera was built by NASA Goddard Space Flight Center, Greenbelt, Md. The camera’s development was led by Dr. Giovanni Fazio of Smithsonian Astrophysical Observatory, Cambridge, Mass.

Additional information about the Spitzer Space Telescope is available at http://www.spitzer.caltech.edu.

Original Source: NASA/JPL News Release

Sea Launch Sends Telstar 18 Into Orbit

Sea Launch Company deployed Loral?s Telstar 18 communications satellite into orbit tonight from its ocean-based platform on the Equator. Early data indicate all systems aboard the spacecraft are in excellent condition.

The Sea Launch Zenit-3SL rocket lifted off at 8:59 pm PDT (3:59 GMT , June 29), as scheduled, from the Odyssey Launch Platform, positioned at 154 degrees West Longitude. On its way to a final orbital position at 138 degrees East Longitude, the spacecraft was separated into a reduced apogee orbit. A ground station in Perth, Australia, acquired the spacecraft?s first signal, shortly after spacecraft separation.

After the completion of the mission, Jim Maser, president and general manager of Sea Launch, said, ?We are still assessing the data and we are optimistic the spacecraft will achieve its specified lifespan on orbit. We are supporting our Loral customer in this assessment. We will issue additional information as it becomes available.?

Built by Space Systems/Loral and operated by Loral Skynet ? both subsidiaries of Loral Space & Communications ? the high-powered 1300-model spacecraft carries 54 active transponders, 16 Ku-band transponders and 38 C-band transponders. Once operational in the next few weeks, the Ku-band will reach China, India, Taiwan and Hong Kong, while the C-band capacity will cover Asia, Australia, New Zealand, the Pacific islands and Hawaii. The satellite will host cable programming, direct-to-home broadcasting, Internet, VSAT and IP-based two-way services within Asia while providing an inter-connect to the United States.

Sea Launch Company, LLC, headquartered in Long Beach, Calif., and marketed through Boeing Launch Services (www.boeing.com/launch), is the world?s most reliable commercial heavy-lift launch services provider. This multinational partnership offers the most direct and cost-effective route to geostationary orbit. With the advantage of a launch site on the Equator, the reliable Zenit-3SL rocket can lift a heavier spacecraft mass or provide longer life on orbit, offering best value plus schedule assurance. For additional information and images of this mission, please visit the Sea Launch website at: www.sea-launch.com

Original Source: Boeing News Release

Air Leak Culprit Nearly Found

International Space Station (ISS) engineers are closing in on determining what caused a problem with Astronaut Mike Fincke’s Russian spacesuit. The malfunction stopped the Expedition 9 crew’s spacewalk just as it was getting started.

The primary oxygen bottle on Fincke’s Orlan suit began losing pressure faster than expected. Fincke was not in danger, but the crew was directed to return to the airlock, close the hatch and end the spacewalk after about 14 minutes.

The earliest the spacewalk could be rescheduled is Tuesday, June 29 based on Russian ground communications coverage.

During evaluations today, Russian specialists had the crew focus on an injector switch that increases the flow of oxygen into the spacesuit. The crew was asked to manipulate the switch on-and-off several times. Also discussed was the status of an indicator light on the suit for the injector system.

The Russian flight control team assured Expedition 9 Commander Gennady Padalka and Fincke, they believe the crew executed the spacewalk procedures well and didn’t do anything that would have caused the decrease in pressure. The crew was also told to expect to use the same suits when the spacewalk is rescheduled.

Investigations into the cause of the decrease in oxygen tank pressure will continue throughout the weekend. The ISS Mission Management Team will discuss the progress of analysis and plans Tuesday morning. The goal of the spacewalk is to replace a faulty circuit breaker on the exterior of the ISS to restore power to a gyroscope that helps control the Station’s orientation in orbit.

Yesterday, Fincke and Padalka opened the Pirs docking compartment hatch at 5:56 p.m. EDT. Immediately after Fincke floated out of the airlock, flight controllers in Moscow saw readings that indicated Fincke’s suit was losing oxygen pressure.

The spacewalkers returned to the airlock and closed the hatch. After conducting preliminary troubleshooting activities, Padalka and Fincke were asked to remove the Orlan spacesuits and assist with troubleshooting of Fincke’s suit. The duration of the spacewalk was 14 minutes, 22 seconds.

Fincke told Mission Control in Houston, he was pleased flight controllers in Moscow had discovered the oxygen tank problem so quickly and thanked both control teams for their efforts.

The ISS has four Control Moment Gyroscopes (CMGs) that are designed to control which way the Station is pointed as it orbits the Earth. CMG 1 failed about two years ago and will be replaced during the next Space Shuttle mission. CMG 2 was taken off line April 21 when a circuit breaker failed. Power to CMG 2 should be restored after the spacewalk. Meanwhile, the two other CMGs are adequately controlling the Station’s orientation.

Original Source: NASA News Release

This Star Just Shut Down

An international team of astronomers, studying the left-over remnants of stars like our own Sun, have found a remarkable object where the nuclear reactor that once powered it has only just shut down. This star, the hottest known white dwarf, H1504+65, seems to have been stripped of its entire outer regions during its death throes leaving behind the core that formed its power plant.

Scientists from the United Kingdom, Germany and the USA focused two of NASA’s space telescopes, the Chandra X-ray observatory and the Far Ultraviolet Spectroscopic Explorer (FUSE), onto H1504+65 to probe its composition and measure its temperature. The data revealed that the stellar surface is extremely hot, 200,000 degrees, and is virtually free of hydrogen and helium, something never before observed in any star. Instead, the surface is composed mainly of carbon and oxygen, the ‘ashes’ of the fusion of helium in a nuclear reactor. An important question we must answer is why has this unique star lost the hydrogen and helium, which usually hide thestellar interior from our view?

Professor Martin Barstow (University of Leicester) said. ‘Studying the nature of the ashes of dead stars give us important clues as to how stars like the Sun live their lives and eventually die. The nuclear waste of carbon and oxygen produced in the process are essential elements for life and are eventually recycled into interstellar space to form new stars, planets and, possibly, living beings.’

Professor Klaus Werner (University of TUbingen) said. ‘We realized that this star has, on astronomical time scales, only very recently shut down nuclear fusion (about a hundred years ago). We clearly see the bare, now extinct reactor that once powered a bright giant star.’

Dr Jeffrey Kruk (Johns Hopkins University) said: ‘Astronomers have long predicted that many stars would have carbon-oxygen cores near the end of their lives, but I never expected we would actually be able to see one. This is a wonderful opportunity to improve our understanding of the life-cycle of stars.’

The Chandra X-ray data also reveal the signatures of neon, an expected by-product of helium fusion. However, a big surprise was the presence of magnesium in similar quantities. This result may provide a key to the unique composition of H1504+65 and validate theoretical predictions that, if massive enough, some stars can extend their lives by tapping yet another energy source: the fusion of carbon into magnesium. However, as magnesium can also be produced by helium fusion, proof of the theory is not yet ironclad. The final link in the puzzle would be the detection of sodium, which will require data from yet another observatory: the Hubble Space Telescope. The team has already been awarded time on the Hubble Space Telescope to search for sodium in H1504+65 next year, and will, hopefully, discover the final answer as to the origin of this unique star.

Original Source: RAS News Release

Cassini’s Best View of Titan Yet

The Cassini spacecraft has beamed back a new, more detailed image of smog-enshrouded Titan.

This view represents an improvement in resolution of nearly a factor of three over the previous Cassini image release about Titan. The observed brightness variations are real on scales of a hundred kilometers or less.

The image was obtained in the near-infrared (centered at 938 nanometers) through a polarizing filter. The combination was designed to reduce the obscuration by atmospheric haze. The haze is more transparant at 938 nm than it is at shorter wavelengths and light of 938 nm wavelength is not absorbed by methane gas in Titan’s atmosphere. Light at this wavelength consequently samples the surface, and the polarizer blocks out light scattered mainly by the haze. This is similar to the way a polarizer, put on the front of a lens of a hand-held camera, makes distant objects more clear on the Earth.

The superimposed coordinate system grid in the accompanying image at right illustrates the geographical regions of the moon that are illuminated and visible, as well as the orientation of Titan ? north is up and rotated 25 degrees to the left. The yellow curve marks the position of the boundary between day and night on Titan.

This image shows about one quarter of Titan’s surface, from 0 to 70 degrees West longitude, and just barely overlaps part of the surface shown in the previous Titan image release. Most of the visible surface in this image has not yet been shown in any Cassini image release.

The image was obtained with the narrow angle camera on June 14, 2004, at a phase, or Sun-Titan-spacecraft, angle of 61 degrees and at a distance of 10.4 million kilometers (6.5 million miles) from Titan. The image scale is 62 kilometers (39 miles) per pixel. The image was magnified by a factor of two using a linear interpolation scheme. No further processing to remove the effects of the overlying atmosphere has been performed.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Office of Space Science, Washington, D.C. The imaging team is based at the Space Science Institute, Boulder, Colorado.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.

Book Review: President’s Commission on Implementation of U.S. Space Exploration Policy

On January 17, 2004, President Bush announced his new vision for human spaceflight. The space shuttle would fly again, to complete the International Space Station. And then the next stage in human space exploration would begin, with humans landing on the Moon by 2015-2020; missions to Mars will follow. He announced a new commission would be formed, led by Edward “Pete” Aldridge to figure out the best way to implement this vision.

The commissioners conducted five public forums and fact finding missions. They interviewed 94 witnesses, including NASA employees, astronauts, academics, media, students, labour unions, space advocates, and many of the agency’s biggest critics. Three months after they began, the commissioners delivered their 64-page report to the President and the public.

This report lays out what I think is a realistic strategy of how to change NASA so that it’s better equipped to accomplish this vision. But I think the commissioners went a step further and got to the heart of what’s wrong with NASA, and offered solutions to get the agency back on track.

The commissioners suggest that “the space vision must be managed as a national priority”, and offer ideas: national advisors, representatives at federal agencies, commissions and councils. This could be layers of extra bureaucracy, or effective oversight. I’m not sure which it would be.

It goes on to make a series of recommendations on how to make the private industry assume a pivotal role in space exploration, by providing services to NASA, especially supplying low-Earth orbit. The commission suggests that NASA should become a customer, purchasing launch services and other products from a healthy private space industry. NASA’s role should be largely limited to science, and the risky research and development where there is “irrefutable demonstration that only government can perform the proposed activity.” I’d like to see how you measure an “irrefutable demonstration”, but that’s good, strong language.

The report goes on to suggest how risky technologies should be identified, directed into mature technologies, and then transitioned into the private sector. This is key. If business is unwilling to take a risk on nuclear propulsion, then NASA – an innovative and adventurous NASA – can swoop in, figure out if it’s possible, build a prototype, and then hand it off to private industry. This could be done directly by NASA, or through competitions like the X Prize ($1 billion for the first company to put a human on the Moon, for example). It’s one of the most exhilarating visions for NASA I can imagine, and I’m sure the people working there would be inspired too.

“The space industry will become a national treasure”, suggests the report. It encourages NASA to dig deep throughout the nation to find the best ideas, people and technologies and get them working to fulfill the exploration vision. I like the sound of that; it’s a 180-degree departure from the agency’s current reputation for close-mindedness. If you’re on the outside right now, you have to fight tooth-and-nail to get your great ideas considered by NASA. This created the bad blood between NASA and private industry today. The commissioners set a great example preparing the report, and let anyone provide ideas through the public forums, and via their website – 6,000 written comments were recieved. Many of these freely offered ideas ended up being quoted word-for-word in the report.

The commissioners suggest that NASA should embrace the international space community to develop future endeavors in space. That’s fine, but a similar vision created the International Space Station. Perhaps a better direction would be to allow NASA to work with suppliers outside of the US. Competing against Russian rocket builders might just light a fire under Lockheed Martin and Boeing.

The report reminds us that a large part of NASA is its role in scientific discovery, and encourages the agency to connect with the scientific community to hear their priorities. The current state is a severe disconnect. Although NASA has enabled some terrific science, it’s funneled billions of dollars into research that has more to do with politics than science. If NASA can figure out how to rebalance this, scientists would be much happier.

Finally, the commission recommends that NASA do a better job of connecting to the public; to encourage future generations of scientists, aerospace engineers and software programmers to direct their careers towards space exploration. I’m in the media, and I can tell you that NASA could go a long way to improving its relations with us… and you, the public. It feels secretive and controlling, dispensing information carefully and selectively. Why aren’t astronauts making the talk show circuit? Where are the reality shows? I want new episodes of Cosmos, maybe hosted by Dr. Brian Greene and Dr. Michio Kaku. Just look at the success of the television show CSI, it’s entertaining and scientific.

Before I started reading the report, I was worried it would either be too aggressive or just plain boring. Instead, the Aldridge report was realistic; perhaps the best compliment I could heap on it. It was very entertaining to read, and I was constantly nodding my head in agreement.

It’s realistic because it recognizes that NASA already has many assets, in equipment, programs, and personnel. These can evolve, improving what works and discarding what doesn’t. Radical space advocates want to see the agency scoured. Disband the centres and fire everyone. That makes me cringe to think what kind of assets and goodwill would get flushed down the toilet. Not to mention, it would be political suicide.

This report suggests, no… demands, that NASA and private enterprise sit down at the table and work things out. Get to the bottom of why the agency has resisted its influence in the past, and see the wheels of free enterprise spinning again. Get the burden off the shoulders of the taxpayer and into grateful hands of business. When people ask, “what’s the point of space exploration, why should we spend $15 billion a year on this when we should be feeding the poor”, it demonstrates how NASA has failed to create a self sustaining spacefaring industry.

My main concern with the Aldridge commission’s report is that it doesn’t do enough to define the “critical success factors”. That’s management speak for the things you can point to which indicate you’re on the right track. The report encourages NASA to become sustainable, affordable, and credible, but doesn’t provide the details about what that agency would look like. The trick with critical success factors is they aren’t goals, they’re principles. They guide your organization into a virtuous spiral of improvement. A responsible leader provides followers with the vision, and then backs it up with these principles to help everyone guide their efforts – it prevents an organization from going off the rails in the future.

In recent years NASA has seemed to be in the business of maintaining its existence. Fill an organization with people regularly under attack from budget cuts, public mistakes, taxpayer displeasure, and a non-existent job market, and it shouldn’t come as a surprise that people are mainly looking to protect their jobs. That the thrilling vision and enthusiasm for space exploration has been watered down by politics and bureaucracy.

The easiest time to change someone’s mind in this situation – someone would otherwise maintain the status quo – is when something disastrous happens to confront their world view. The Columbia disaster was just this event. It briefly drove a stake deep into the heart of the bureaucracy and I know it caused every single person in NASA to wonder what went wrong.

And be open for change.

NASA employees and managers have an open mind right now. Congress and the Senate understand that bad decisions by government contributed to the situation. This affected President Bush, and he announced a new direction; an exciting vision to return to the Moon and then head off to Mars.

Although I’m hard pressed to think of something more exciting for space exploration than humans setting foot on Mars, I’m more excited by the possibility that NASA will reinvent itself from an organization that defends itself and restricts free enterprise, to one that embraces entrepreneurs and ensures that mankind returns to space… for good.

NASA needed a plan which would inject free enterprise deep into its bloodstream, while maintaining its value to science, and developing the risky technologies that business won’t touch. In my opinion, this is what they got from Aldridge and the rest of the commissioners. Good job.

Now, let’s see President Bush embrace the plan. Let’s see NASA implement it in a way that respects its employees and takes advantage of their creativity, experience, and infrastructure. Let’s judge their progress by how well they stick to their principles.

Return to space, and never turn back. Failure is not an option.

Read the report for yourself.

NASA Begins its Transformation

In the latest of what will be ongoing briefings, Administrator Sean O’Keefe today announced a transformation of NASA’s organization structure designed to streamline the agency and position it to better implement the Vision for Space Exploration.

In a report released last week, the President’s Commission on Implementation of U.S. Space Exploration Policy found, “NASA needs to transform itself into a leaner, more focused agency by developing an organizational structure that recognizes the need for a more integrated approach to science requirements, management, and implementation of systems development and exploration missions.”

“Our task is to align Headquarters to eliminate the ‘stove pipes,’ promote synergy across the agency, and support the long-term exploration vision in a way that is sustainable and affordable,” said Administrator O’Keefe. “We need to take these critical steps to streamline the organization and create a structure that affixes clear authority and accountability.”

This transformation fundamentally restructures NASA’s Strategic Enterprises into Mission Directorates to better align with the Vision. It also restructures Headquarters support functions and clarifies organizational roles and responsibilities. The Mission Directorate organizational structure includes:

* Aeronautics Research: Research and develop aeronautical technologies for safe, reliable and efficient aviation systems

* Science: Carry out the scientific exploration of the Earth, Moon, Mars and beyond; chart the best route of discovery; and reap the benefits of Earth and space exploration for society. A combined organization is best able to establish an understanding of the Earth, other planets and their evolution, bring the lessons of our study of Earth to the exploration of the Solar System, and to assure the discoveries made here will enhance our work there

* Exploration Systems: Develops capabilities and supporting research and technology that enable sustained and affordable human and robotic exploration; includes the biological and physical research necessary to ensure the health and safety of crew during long duration space flight

* Space Operations: Direct space flight operations, space launches and space communications, as well as the operation of integrated systems in low-Earth orbit and beyond

Two agency-wide priorities will continue with direct responsibility for all related activities across NASA.

* Safety and Mission Assurance Officer: Reports directly to the Administrator and reflects NASA’s commitment to provide a clear and direct line to agency senior leadership for issues regarding safety

* Chief Education Officer: Directs the agency’s important work to improve scientific and technological literacy and inspire a new generation of explorers

NASA functional offices will be restructured as Mission Support Offices. Headquarters and field center offices will be aligned to improve communications and responsibility.

The major Mission Support Offices are:

* Chief Financial Officer (CFO): Conducts all financial matters, including procurement and small and disadvantaged business activities. All field center financial officers report directly to the Headquarters CFO to better address critical financial issues

* Associate Administrator for Institutions and Management: Responsible for providing operational and management support for Headquarters; directs a full range of activities relating to personnel and institutional management across the agency

* Chief Information Officer: Responsible for the development of an integrated focus on information resource management strategies, policies and practices

* Chief Engineer: Ensures the development efforts and missions operations are being planned and conducted on a sound engineering basis; assures independent technical authority within the agency’s engineering, operations and safety organizations

* Chief of Strategic Communications: Directs NASA’s communication efforts in Public Affairs, Legislative Affairs and External Relations; responsible for internal communications management

* General Counsel: Responsible for the legal aspects of all NASA’s activities; manages the agency’s intellectual property and ethics programs

To improve the decision-making process, NASA will create:

* Strategic Planning Council: Chaired by the NASA Administrator, the Council develops multi-year strategic plans, strategic roadmaps, and a multi-year detailed plan that forms the basis for policies and budgets

* Director of Advanced Planning: Responsible for the preparation of options, studies and assessments for the Strategic Planning Council

* Chief Operating Officer Council: Chaired by the Deputy Administrator, implements direction provided by the Strategic Planning Council and develops standard administrative practices to build on the President’s Management Agenda

The Associate Deputy Administrator for Systems Integration is responsible for strategic and systems integration across Mission Directorates and mission support functions

The agency will also redefine its relationships with the NASA Field Centers by developing clear and straightforward lines of responsibility and accountability. Specific Mission Associate Administrators will be assigned as Headquarters Center Executives. They will have oversight of field center performance in implementing agency policies and programs. The Associate Administrator for Institutions and Management will address field center infrastructure concerns.

The changes outlined today become effective August 1, 2004. They represent the next step in implementing the recommendations of the President’s Commission on Implementation of U.S. Space Exploration Policy and reflect NASA’s ongoing efforts to apply the findings and recommendations of the Columbia Accident Investigation Board across the agency.

Over the next several weeks, the Administrator will engage teams in each NASA location to provide front line guidance on implementing their early stages of the transformation plan. The discussions will be the precursor for a renewed commitment to mission success and excellence in an employee-centric organization.

“This transformation will be an evolutionary process, exploring new ways to move forward and implement change. We’ll also be engaging other government agencies, industry, academia and the international community to assist us in developing the tools and processes we need to successfully advance the Vision for Space Exploration,” added Administrator O’Keefe. “Doing so will enable us to take the next bold steps into space and rekindle the innovation and entrepreneurial skills that is our legacy to humankind.”

Additional presentation information and a new NASA organization chart is available on the Internet at:

http://www.nasa.gov/formedia

Original Source: NASA News Release

Wallpaper: Phoebe

During its historic close encounter with Phoebe, the Cassini spacecraft captured a series of high resolution images of the small moon, six of which have been mosaicked together to create this detailed view.

Phoebe shows an unusual variation in brightness over its surface due to the existence on some crater slopes and floors of bright material ? thought to contain ice ? on what is otherwise one of the darkest known bodies in the solar system. Bright streaks on the rim of the large crater in the North (up in this image) may have been revealed by the collapse of overlying darker material from the crater wall. The large crater below right-of-center shows evidence of layered deposits of alternating bright and dark material. A possible mechanism for this apparent layering was discussed in an earlier image release (PIA 06067).

Hints of Phoebe?s irregular topography can be seen peeking out from the shadows near the lower left and upper left parts of the image. These are real features ? possibly crater rims or mountain peaks ? that are just being hit by the first light of sunrise on Phoebe.

Phoebe?s surface shows many large- and small-scale craters. The emerging view of Phoebe is that it might have been part of an ancestral population of icy, comet-like bodies, some of which now reside in the Kuiper Belt beyond Neptune.

The images in this mosaic were taken in visible light with the narrow-angle camera at distances ranging from 15,974 kilometers (9,926 miles) to 12,422 kilometers (7,719 miles). The image scale is 74 meters (243 feet) per pixel. Contrast in the image has been enhanced slightly to improve visibility.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Office of Space Science, Washington, D.C. The imaging team is based at the Space Science Institute, Boulder, Colorado.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.

Original Source: CICLOPS News Release

New Instrument Finds its First Supernova

The Nearby Supernova Factory, an international collaboration of astronomers and astrophysicists, has announced that SNIFS, the Supernova Integral Field Spectrograph, achieved “first light” during the early morning hours of Tuesday, June 8, when the new instrument acquired its first astronomical target, a Type Ia supernova designated SN 2004ca. Type Ia supernovae are the kind used by astronomers to measure the expansion of the universe.

Analysis of the initial data, plus a separate observation of the newly discovered supernova SN 2004cr on Sunday, June 20th, confirm that SNIFS ? while still in its commissioning phase ? is meeting its design goals as a remarkable new tool for observing supernovae.

SNIFS, which was recently mounted on the University of Hawaii’s 2.2-meter telescope atop Mauna Kea on the island of Hawaii, is an innovative instrument designed to track down the idiosyncrasies and precise distances of Type Ia supernovae by simultaneously obtaining over 200 spectra of each target, its home galaxy, and the nearby night sky.

SNIFS is a crucial element in the international Nearby Supernova Factory (SNfactory), initiated at the Department of Energy’s Lawrence Berkeley National Laboratory. The SNfactory’s goal is to find and study over 300 nearby Type Ia supernovae in order to reduce uncertainties about these foremost astronomical “standard candles,” whose measurement led to the discovery that the expansion rate of the universe is increasing.

“Better knowledge of these extraordinarily bright and remarkably uniform objects will make them even better tools for measuring the cosmos,” says astronomer Greg Aldering of Berkeley Lab’s Physics Division, who leads the SNfactory collaboration. “Type Ia supernovae are the key to understanding the mysterious dark energy that’s causing the universe to expand ever faster.”

The body of the SNIFS instrument was built by the SNfactory’s French collaborators, members of the Laboratoire de Physique Nucl?aire et de Haute Energies (LPNHE) in Paris, the Centre de Recherche Astronomique de Lyon (CRAL), and the Institut de Physique Nucl?aire de Lyon (INPL), supported by the Institut National de Physique Nucl?aire et de Physique des Particules (CNRS/IN2P3) and the Institut National des Sciences de l’Univers (CNRS/INSU). Berkeley Lab, with help from Yale University, developed the cameras used to detect the light from SNIFS, while the University of Chicago developed instruments to monitor the performance of SNIFS.

The SNIFS instrument produces a spectrum at each position within a six- by six-arc-second region around the target supernova, including its home galaxy and surrounding sky, by using an “integral field unit” consisting of an array of individual lenslets. Light is extracted from the telescope’s field of view by a small prism and directed to either blue-sensitive or red-sensitive, eight-megapixel, astronomical CCD cameras. Together these cameras collect all the optical light from each supernova.

A separate photometry camera, running in parallel with the spectrograph under identical observing conditions, allows spectra to be corrected for variables like thin cloud cover. A guide camera keeps the spectrograph precisely aligned on target by measuring the position of a guide star within the telescope’s wider field of view once each second, adjusting the aim if necessary.

Flown to Hilo in March and assembled in working order at sea level, SNIFS was taken apart, carried to the 4,245-meter (nearly 14,000-foot) summit of Mauna Kea, and reassembled on the University of Hawaii’s 2.2-meter telescope on April 6.

“At sea level we made sure everything was in order and also rehearsed the assembly,” says Aldering. “When you get to 14,000 feet things get tricky. Everybody carries a ‘dumb list’ so they don’t start off to do something and then forget what it was.”

Two months of engineering to align and calibrate the instrument on the telescope preceded SNIFS observation of its first new Type Ia supernova, SN 2004ca, on June 8th, in the constellation Cygnus, the swan. This was followed by the observation of SN 2004cr in the constellation Cepheus, the king, on June 20th. Shortly routine observations of SNfactory-discovered supernovae will begin.

“Now that SNIFS is in regular operation,” Aldering says, “our daily lives have changed dramatically.” After years of planning and long-distance meetings, including monthly videoconferences, “the activity level has escalated ? every day we have to react instantly as our new supernova data come pouring in.”

A full schedule ahead
The SNfactory strategy has two “pipelines,” the first being a supernova search using automated wide-field sky surveys. Data are provided by the QUEST-II 160-megapixel camera, built by Yale University and Indiana University and operated at Palomar Observatory by the QUEST-II group, as well as by the Jet Propulsion Laboratory’s Near Earth Asteroid Tracking team and the California Institute of Technology. The data are transmitted by the High-Performance Research and Education Network to the National Energy Research Scientific Computing Center (NERSC) at Berkeley Lab for identification of likely supernova candidates.

The ideal candidate is a recently exploded Type Ia supernova that is near enough for accurate measurement of its spectrum and light curve (its rising and falling brightness) but far enough away to be “in the smooth Hubble flow” ? meaning that its redshift is mostly due to the expansion of the universe alone, unaffected by the motion of its home galaxy through space.

The SNfactory’s search phase has been operating for over a year, although not at full capacity. “The search will now be going full steam,” Aldering says. “We’ll be getting a few candidates each night of the year ? more than the entire current worldwide rate of discovery.”

SNIFS is mounted on the University of Hawaii’s 2.2-meter telescope atop Mauna Kea on the island of Hawaii.

The second SNfactory pipeline passes the search candidates on to SNIFS, where the type and redshift of each supernova are determined and the most promising are selected and scheduled for more detailed study. The SNfactory uses the University of Hawaii’s telescope three times a week for half a night ? the half beginning at midnight, as a courtesy to local observers ? with SNIFS available to other projects at other times.

Eventually SNIFS will operate fully automatically. Remote control of the telescope and spectrograph was first done from Hilo, Hawaii and is now being done from Berkeley Lab and France.

SNIFS can determine a given Type Ia’s specific physical characteristics including, for example, whether or not it is unusually energetic or how much its light may have been dimmed by dust in its home galaxy. Such unparalleled spectrographic and photometric detail makes it possible to take advantage of a unique characteristic of Type Ia supernovae: that “they can be calibrated individually, not simply statistically,” Aldering says. “We’ll be able to measure the luminosity with confidence. Knowing the luminosity, we can tell you the distance with precision.”

By collecting large numbers of Type Ia supernovae in the Hubble flow, SNfactory scientists will be able to pin down the low-redshift end of the luminosity-redshift diagram upon which measures of the universe’s expansion rate are based. This, plus detailed understanding of the physical factors that cause small variations in Type Ia spectra and light curves, will improve the accuracy of the high-redshift measurements crucial to choosing among the many competing theoretical models of dark energy.

Members of the Nearby Supernova Factory team include Greg Aldering, Peter Nugent, Saul Perlmutter, Lifan Wang, Brian C. Lee, Rollin Thomas, Richard Scalzo, Michael Wood-Vasey, Stewart Loken, and James Siegrist from Berkeley Lab; Jean-Pierre Lemonnier, Arlette Pecontal, Emmanuel Pecontal, Christophe Bonnaud, Lionel Capoani, Dominique Dubet, Francois Heunault, and Blandine Lantz from CRAL; Gerard Smadja, Emmanuel Gangler, Yannick Copin, Sebastien Bongard, and Alain Castera from INPL; Reynald Pain, Pierre Antilogus, Pierre Astier, Etienne Barrelet, Gabriele Garavini, Sebastien Gilles, Luz-Angela Guevara, Didier Imbault, Claire Juramy, and Daniel Vincent from LPNHE; and Rick Kessler and Ben Dilday from the University of Chicago. Recently the astrophysics group at Yale University, under the leadership of Charles Baltay, has joined the Nearby Supernova Factory.

The Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California. Visit our website at http://www.lbl.gov.

Original Source: Berkeley Lab News Release

As Requested, Bigger Photos

Thanks for all your feedback, I really appreciate it. I can’t believe how positive everyone was. The common thread was: “you’ve got a good thing going… don’t mess it up”. I get the message. 🙂 One thing people did want to see; however, was a way to enlarge pictures even more (will your insatiable hunger for images ever be fulfilled?). It was easy to do, so I’ve made the change with today’s issue. When you look at the full story, the big picture is clickable, and takes you to an even larger version of the image, so you can look at more detail, or turn it into a wallpaper (right-click and then select “Set as Wallpaper). Then just click back in your browser to get back to the story. Any further expansion of images would probably destroy the Universe, so we’ll just keep it as is.

If anything else springs to mind, please let me know.

Thanks!

Fraser Cain
Publisher
Universe Today