Posted on by Fraser Cain

New Evidence that Stars Form Like Dominos

Image credit: Hubble

An international team of astronomers have gathered new evidence to support the “domino theory” of star formation; that star formation occurs in sequence in galaxies driven by the movements of gas and stars at the core. A new instrument attached to the 8m Gemini South Telescope, called CIRPASS, allowed the astronomers to measure the composition of a whole range of stars at the centre of galaxy M83. A detailed analysis of the data is now underway.

An international team of astronomers have used a unique instrument on the 8m Gemini South Telescope to determine the ages of stars across the central region of the barred spiral galaxy, M83. Preliminary results provide the first hints of a domino model of star formation where star formation occurs in a time sequence, driven by the movements of gas and stars in the central bar.

The new instrument, called CIRPASS, simultaneously produces 500 spectra, taken from across the whole region of interest, which act as a series of ‘fingerprints’. Encoded in these ‘fingerprints’ is not only all the information the team required to determine when individual groups of stars formed, but also information on their movements and chemical properties. Dr. Johan Knapen, project co-investigator, ‘The unique combination of a state-of-the-art instrument like CIRPASS with one of the most powerful telescopes available is now providing us with truly sensational observations.’

M83 is a grand design spiral galaxy undergoing an intense burst of star formation in its central bar region. Large scale images, of the visible light from the galaxy, taken with ground based telescopes, show a pronounced bar across the middle of the galaxy) seen as the diagonal white structure in figure 1 . Astronomers believe that it is the influence of this bar which leads a concentration of gas in the central regions of the galaxy from which stars are born. ‘The central region of M83 is enshrouded in dust, but by using CIRPASS, which operates in the infra-red not the visible, we are able to see through this dust and investigate the hidden physical processes at work in the galaxy,’ said Dr Ian Parry, leader of the CIRPASS instrumentation team.

Two competing theories strive to explain the burst of star formation in the centre of the galaxy, M83. One theory suggests that stars form randomly across the whole nuclear region. A second model, favoured by the observational team, proposes that star-formation is triggered by the bar structure. In this model, the rotation of gas and stars in the bar causes stars to be formed sequentially, in a domino manner.

Using a technique first demonstrated by Dr. Stuart Ryder and colleagues, the team searched for a hydrogen emission feature, the Paschen-beta line, within the galaxy’s ‘fingerprints’. The measurement of this feature indicates the presence of hot young stars. By comparing the strengths of the Paschen-beta emission with the amount of absorption from carbon-monoxide (arising in the cool atmospheres of old giant stars) the team are able determine the age of the stars in each region of the galaxy. ‘A detailed analysis of the data is underway but initial results hint at a complex sequence of star formation,’ said Dr Robert Sharp, instrument support scientist with CIRPASS.

Preliminary analysis of other emission features (due to Paschen-beta and ionized iron) revealed a potentially intriguing result. ‘Ionized iron enables us to trace past supernova explosions. The observations indicate that energy from exploding stars (supernovae) may be being passed into regions of undisturbed gas causing further massive star formation.’ said Dr. Stuart Ryder, principle investigator.

While some members of the instrument team are presenting their work at the Royal Society Science Exhibition in London, CIRPASS is back on the Gemini South Telescope in Chile, performing the next set of observations.

Original Source: Cambridge News Release

Posted on by Fraser Cain

James Kennedy New Director for Kennedy Space Center

Image credit: NASA

James M. Kennedy was selected by NASA today as administrator of the agency’s Kennedy Space Center (KSC) in Florida. Prior to this assignment, Kennedy was the deputy director of NASA’s George C. Marshall Space Flight Center in Huntsville Alabama, and served as a project manager for the X-34 and DC-XA projects. He first joined NASA in 1968 and has received numerous awards during his tenure with the space agency.

William F. Readdy, Associate Administrator for Space Flight at NASA Headquarters in Washington, today named James W. Kennedy as the new Director of the agency’s Kennedy Space Center (KSC) in Florida. Kennedy has served as KSC’s Deputy Director since November 2002. He will succeed General Roy Bridges, who was appointed to lead NASA’s Langley Research Center, Hampton, Va., June 13.

“Along with his impeccable credentials, Jim brings stability to KSC at a time when we need it,” Readdy said making the announcement. “As we prepare to implement the findings of the Columbia Accident Investigation Board, Jim’s knowledge of the Space Shuttle and his leadership abilities are essential in making our ‘Return to Flight’ effort a success,” he said.

Prior to his assignment to KSC in 2002, Kennedy was deputy director of NASA’s George C. Marshall Space Flight Center in Huntsville, Ala.

Kennedy also served as project manager for major initiatives, such as the X-34 and the DC-XA, and he led the One NASA effort to help make the agency more effective and efficient by encouraging teamwork across all field centers. In early 1996, he was the manager for Marshall’s Space Shuttle Projects Resident Office at KSC. Kennedy returned to Marshall when he received a Senior Executive Service appointment in September 1996 and was named manager of the Solid Rocket Booster Project.

In 1998, he was selected as the Deputy Director of Science and Engineering, where he was responsible for establishing and maintaining a nationally recognized research and development capability in space research and technology. One year later, he became the Director of Engineering.

“Jim is the right person we need at the helm of the Kennedy Space Center, as we prepare to return to safe flight,” added NASA Administrator Sean O’Keefe. “He’s a distinguished engineer and a devoted public servant. I know his colleagues at KSC will give Jim their full support, and I am confident, under his guidance, the center will meet and exceed all the objectives facing us in the coming months,” O’Keefe said.

Kennedy first joined NASA in 1968 in the Aerospace Engineering Cooperative Education program at KSC. He earned a bachelor’s degree in mechanical engineering from Auburn University, Ala., in 1972. After being called to active duty in the U.S. Air Force, he earned his master’s degree in business administration from Georgia Southern University, Statesboro, in 1977.

Kennedy has received numerous awards during his NASA career, including Marshall’s Leadership Award, NASA’s Silver Snoopy Award, a Distinguished Service Medal and a Meritorious Rank Award. He also has received a Group Achievement Award and several Special Service and Performance Awards. In 2003, Kennedy received the National Space Club’s Astronautics Engineer of the Year Award.

Original Source: NASA News Release

Posted on by Fraser Cain

Columbia Investigators Analyze NASA Culture

Investigators into the Columbia disaster believe they understand the events that led to the destruction of the shuttle, that falling foam created a crack in a critical heat shield. Now they’re looking into the culture and management in NASA to find out how to prevent problems from happening in the future. The accident investigation board said that fully half of their report will include will deal with management problems at NASA that could affect flight safety. The board hopes their recommendations will create a sense of urgency to help the agency create a safer replacement for the aging space shuttle.

Posted on by Fraser Cain

Astronauts Announced For Canadian Arrow

A team of Canadian private rocket builders announced their astronaut selection today, as part of their preparations to launch the Canadian Arrow – a ship based on the original V2 design used in World War 2. The six astronauts include three pilots, an aerospace engineer, a Ukrainian astronaut (who was a backup for a 1997 space shuttle mission), and a 28-year old who has the potential to be the youngest astronaut ever. The Canadian Arrow is considered one of the front-runners to win the X-Prize, which gives $10 million to the first private group to place a three-person team in space.

Posted on by Fraser Cain

Watch the Discovery Channel Tonight

Just to let you know, the Discovery Channel is planning to air two documentaries about the space shuttle Columbia disaster. The first is called “Coming Home: The Science of Re-entry”, and the second is “Columbia’s Final Mission: 16 Days” – they’ll be broadcasting them one after the other, so set aside two hours. Check your local listings, but I know they’re playing on both the US and Canadian stations.

Fraser Cain
Publisher
Universe Today

Posted on by Fraser Cain

Summer Will Bring Mars’ Closest Approach

Image credit: Ron Wayman

Earth and Mars are rapidly converging, and are expected to reach their closest point on August 27, 2003. Already amateur astronomers with modest telescopes are reporting they can see features on the surface of Mars with greater clarity, including the planet’s polar ice caps. On August 27, the two planets will only be 56 million km apart; the closest they’ve been for 60,000 years. The planet is currently visible in the morning sky, but over the course of the summer it will move to the point that it’s easy to spot in the evening sky – it’ll be hard to miss since it’ll be nearly the brightest object in the sky.

Count slowly: one one-thousand, two one-thousand, three one-thousand…. You just got about 30 km closer to the planet Mars.

Earth and Mars are rapidly converging. On August 27, 2003–the date of closest approach–the two worlds will be 56 million km apart. That’s a long way by Earth standards, but only a short distance on the scale of the solar system. NASA, the European Space Agency and Japan are all sending spacecraft to Mars this year. It’s a good time to go.

Between now and August, Mars will brighten until it “blazes forth against the dark background of space with a splendor that outshines Sirius and rivals the giant Jupiter himself.” Astronomer Percival Lowell, who famously mapped the canals of Mars, wrote those words to describe the planet during a similar close encounter in the 19th century.

Already Mars is eye-catching. You can see it this month in the morning sky–bright, steady and remarkably red. Only Venus near the sun is brighter.

Amateur astronomers looking through backyard telescopes have reported in recent days great views of Mars’s south polar cap. Made of frozen water and carbon dioxide (“dry ice”), it reflects sunlight well. “I can see the polar ice vividly using my 8-inch telescope,” says Ron Wayman of Tampa, Florida. He’s also spotted “some faint darker-shaded areas on the surface.”

Such markings will become clearer in the weeks ahead. On June 1st Mars was 12.5 arcseconds across and it glowed like a -1st magnitude star. On August 27th it will be twice as wide (25 arcseconds) and six times brighter (magnitude -2.9).

Much has been made of the fact that the August 27th encounter with Mars is the closest in some 60,000 years. Neanderthals were the last to observe Mars so favorably placed. This is true. It’s also a bit of hype. Mars and Earth have been almost this close many times in recent history.

Some examples: Aug. 23, 1924; Aug. 18, 1845; Aug. 13, 1766. In each case Mars and Earth were approximately 56 million km apart.

Astronomers call these close encounters “perihelic oppositions.” Perihelic means Mars is near perihelion–its closest approach to the sun. (The orbit of Mars, like that of all planets, is an ellipse, so the distance between the sun and Mars varies.) Opposition means that the sun, Earth and Mars are in a straight line with Earth in the middle. Mars and the sun are on opposite sides of the sky. When Mars is at opposition and at perihelion–at the same time–it is very close to Earth.

August 27th is indeed the best perihelic opposition since the days of the Neanderthals, but it scarcely differs from other more recent ones. That’s fine because all perihelic oppositions of Mars are spectacular.

Mars is a morning planet now. You have to wake up early to see it. Soon, though, it will be more conveniently placed. By mid-July Mars will rise in the east around 11 p.m. local time. In late August it will appear as soon as the sun sets. It won’t be long before everyone can see Mars at a civilized hour.

We’ll be telling more stories about Mars in the weeks ahead. This one, though, is finished. Did you make it to the end? Congratulations! You’re now 2000 km closer to Mars.

Original Source: NASA Science Story

Posted on by Fraser Cain

New Mission to Mercury Approved

A key Japanese government committee has approved a joint Japanese/European mission to the planet Mercury. BepiColombo, named after the late Italian astronomer who worked on the previous mission to Mercury, is expected to launch in 2010 and will contain an orbiter and a lander which will penetrate the surface of the planet. The European Space Agency had committed to the project three years ago, but the Japanese government has yet to supply its share of the funds. This will be the first mission to Mercury since Mariner 10, which went in the 1970s.

Posted on by Fraser Cain

Images Recovered from Columbia Wreckage

Image credit: NASA

NASA has released video and photographs taken by the crew of the space shuttle Columbia while it was still in space. The film was recovered from the wreckage of the shuttle; of the 337 videotapes and 137 rolls of film, only 28 tapes and 21 film rolls were usable. Selected scenes will be broadcast on NASA TV. The Columbia Accident Investigation Board, which is researching the cause of the disaster, gave NASA permission to release the material because it isn’t relevant to the probe.

NASA today released recovered photographs and video taken by the crew of the Space Shuttle Columbia during its scientific research mission in January. The imagery was found during search efforts since the loss of Columbia Feb. 1.

The Columbia Accident Investigation Board recently determined the material was not relevant to their investigation. The imagery documents the STS-107 mission from the crew’s perspective. The imagery includes almost 10 hours of recovered video and 92 photographs. It includes in-cabin, Earth observation and experiment-related imagery. The Shuttle carried 337 videotapes, but only 28 were found with some recoverable footage. The mission carried 137 rolls of film, but only 21 were found containing recoverable photographs.

The imagery is among the more than 84,000 pieces of debris recovered. The debris weighs 84,900 pounds, about 38 percent of the dry weight of Columbia. More than 30,000 people assisted in the search conducted through the combined efforts of NASA, FEMA, EPA, the U.S. and Texas Forest Services. The Columbia Recovery Office at the Johnson Space Center (JSC) was established to continue accepting calls about debris, since the formal search was completed in April. The toll free number to report debris is: 1/866/446-6603.

Selected scenes and photographs will be broadcast on NASA Television today at 12:15 p.m. EDT. News media may obtain the video and photos in their entirety by calling the JSC Media Resource Center at: 281/483-4231. NASA Television is broadcast on AMC-2, transponder 9C, C-Band, located at 85 degrees West longitude. The frequency is 3880.0 MHz. Polarization is vertical and audio is monaural at 6.8 MHz. Information about NASA and the Columbia accident investigation is on the Internet at: http://www.nasa.gov

Original Source: NASA News Release

Posted on by Fraser Cain

New View of Mars

Image credit: NASA/MSSS

The Mars Global Surveyor spacecraft takes a complete picture of Mars every day to track weather and surface frost across the planet. Surveyor has been tracking the planet this way since 1999, for almost two complete Martian years. This recently released image was taken on May 12, 2003 and shows the northern hemisphere in early autumn and the southern hemisphere in spring. The planet’s four large volcanoes are also visible on the left-hand side.

The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) experiment consists of 3 different cameras: a narrow angle imager that provides the black-and-white high resolution views (up to 1.4 meters per pixel) of Mars, and 2 wide angle cameras, observing in red and blue wavelengths, from which color views of the entire planet are assembled each day. The wide angle cameras provide a daily record of changes in martian weather and surface frost as the seasons progress. MGS MOC has obtained a record of martian weather spanning a little over 2 martian years since it began systematic observations in March 1999.

The view of Mars shown here was assembled from MOC daily global images obtained on May 12, 2003. At that time, the northern hemisphere was in early autumn, and the southern hemisphere in early spring. At the left/center of this view are the four large Tharsis volcanoes: Olympus Mons, Ascraeus Mons, Pavonis Mons, and Arsia Mons. Stretching across the center of the globe is the ~5,000 kilometers (~3,000 miles) long Valles Marineris trough system. The seasonal south polar carbon dioxide frost cap is visible at the bottom of this view. A dust storm sweeps across the plains of northern Acidalia at the upper right. North is up, east is right, sunlight illuminates the planet from the left.

Original Source: MSSS News Release

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Four Astronauts Enter Hall of Fame

Four space shuttle veterans were inducted into the Astronaut Hall of Fame at Florida’s Kennedy Space Center Visitor Complex on Saturday. The newest entrants were Daniel Brandenstein, Robert Gibson, Story Musgrave and Sally Ride (the first American woman in space). The event drew hundreds of people – many were tourists – and actor Lance Henriksen (“The Right Stuff” and “Aliens”) presided over the event. They join 48 astronauts already enshrined at the hall.