Cfa in the News ~ Week Ending 1 February 2009

Cfa in the News ~ Week Ending 1 February 2009

Wolbach Library: CfA in the News ~ Week ending 1 February 2009 1. Extrasolar planet 'rediscovered' in 10-year-old Hubble data, Ivan Semeniuk, New Scientist, v 201, n 2693, p 9, Saturday, January 31, 2009 2. Wall Divides East And West Sides Of Cosmic Metropolis, Staff Writers, UPI Space Daily, Tuesday, January 27, 2009 3. Night sky watching -- Students benefit from view inside planetarium, Barbara Bradley, [email protected], Memphis Commercial Appeal (TN), Final ed, p B1, Tuesday, January 27, 2009 4. Watching the night skies, Geoffrey Saunders, Townsville Bulletin (Australia), 1 - ed, p 32, Tuesday, January 27, 2009 5. Planet Hunter Nets Prize For Young Astronomers, Staff Writers, UPI Space Daily, Monday, January 26, 2009 6. American Astronomical Society Announces 2009 Prizes, Staff Writers, UPI Space Daily, Monday, January 26, 2009 7. Students help NASA in search for killer asteroids., Nathaniel West Mattoon Journal-Gazette & (Charleston) Times-Courier, Daily Herald (Arlington Heights, IL), p 15, Sunday, January 25, 2009 Record - 1 DIALOG(R) Extrasolar planet 'rediscovered' in 10-year-old Hubble data, Ivan Semeniuk, New Scientist, v 201, n 2693, p 9, Saturday, January 31, 2009 Text: THE first direct image of three extrasolar planets orbiting their host star was hailed as a milestone when it was unveiled late last year. Now it turns out that the Hubble Space Telescope had captured an image of one of them 10 years ago, but astronomers failed to spot it. This raises hope that more planets lie buried in Hubble's vast archive. In 1998, Hubble studied the star HR 8799 in the infrared, as part of a search for planets around young and relatively nearby stars. The search came up empty. Last year, Christian Marois of the Herzberg Institute of Astrophysics in Victoria, British Columbia, Canada, and colleagues looked at the same star using the Gemini North telescope in Hawaii. They discovered three planets, each about 10 times as massive as Jupiter. They succeeded where the Hubble team failed mainly because of new strategies developed to carefully subtract the star's glare, leaving only the faint infrared glow from its planets. Marois and David Lafreniere, of the University of Toronto in Ontario, Canada, decided to apply their new mathematical tools to the decade-old Hubble image. This involved digitally combining Hubble's views of 23 similar stars that do not have planets to create a reference image nearly identical to that of HR 8799. When they subtracted the reference image from HR 8799's, the outermost of its three planets popped into view. "I felt the same excitement I experienced when we discovered it the first time," says Lafreniere. This opens the door for the discovery of exoplanets simply by reprocessing old Hubble images, says Bruce Macintosh of Lawrence Livermore National Laboratory in California. He suggests that images of at least 200 stars that had been the target of Hubble's exoplanet searches should be re-analysed using the new method. Aspects of the HR 8799 solar system promise more riches. Daniel Fabrycky and Ruth Murray-Clay of the Harvard-Smithsonian Center for Astrophysics in Boston studied the dynamics of the three-planet system and found that the mutual gravitational pull of the massive planets should be enough to make the solar system unstable. They conclude that the planets have survived until now because they have slotted themselves into so-called resonance orbits: each time the outermost planet orbits the star once, they argue, the next one in must orbit twice and the innermost planet four times (www.arxiv.org/abs/0812.0011v1). As the planets trace their elliptical orbits, the 1:2:4 timings would mean that the three planets never gather closely enough as a group to gravitationally upset the system. If such resonances are common, it suggests there could be many more massive planets out there in extrasolar systems that would otherwise have been too unstable to persist. Copyright (c) 2009 Reed Business Information - UK. All Rights Reserved. Record - 2 DIALOG(R) Wall Divides East And West Sides Of Cosmic Metropolis, Staff Writers, UPI Space Daily, Tuesday, January 27, 2009 Text: A new study unveils NGC 604, the largest region of star formation in the nearby galaxy M33, in its first deep, high-resolution view in X- rays. This composite image from Chandra X-ray Observatory data (colored blue), combined with optical light data from the Hubble Space Telescope (red and green), shows a divided neighborhood where some 200 hot, young, massive stars reside. Throughout the cosmic metropolis, giant bubbles in the cool dust and warm gas are filled with diffuse, multi-million degree gas that emits X-rays. Scientists think these bubbles are generated and heated to X- ray temperatures when powerful stellar winds from the young massive stars collide and push aside the surrounding gas and dust. So, the vacated areas are immediately repopulated with the hotter material seen by Chandra. However, there is a difference between the two sides of this bifurcated stellar city. (See annotated image for the location of the "wall".) On the western (right) side, the amount of hot gas found in the bubbles corresponds to about 4300 times the mass of the sun. This value and the brightness of the gas in X-rays imply that the western part of NGC 604 is entirely powered by winds from the 200 hot massive stars. This result is interesting because previous modeling of other bubbles usually predicted them to be fainter than observed, so that additional heating from supernova remnants is required. The implication is that in this area of NGC 604, none or very few of the massive stars must have exploded as supernovas. The situation is different on the eastern (left) side of NGC 604. On this side, the X-ray gas contains 1750 times the mass of the sun and winds from young stars cannot explain the brightness of the X-ray emission. The bubbles on this side appear to be much older and were likely created and powered by young stars and supernovas in the past. A similar separation between east and west is seen in the optical results. This implies that a massive wall of gas shields the relatively quiet region in the east from the active star formation in the west. This study was led by Ralph Tuellmann of the Harvard Smithsonian Center for Astrophysics and was part of a very deep, 16-day long observation of M33 called the Chandra ACIS Survey of M33, or ChASeM33. Copyright (c) 2009 Space Daily, Distributed by United Press International Record - 3 DIALOG(R) Night sky watching -- Students benefit from view inside planetarium, Barbara Bradley [email protected], Memphis Commercial Appeal (TN), Final ed, p B1, Tuesday, January 27, 2009 Text: An inflatable planetarium can be pretty handy, except for the crawling in part. Dozens of adults and kids recently got on all fours to crawl through the gullet-like entrance to Starlab and into its dome-shaped belly. Christ Methodist Day School's portable planetarium, believed to be the only one of its kind in Memphis, was shown to families outside the school for the first time earlier this month. With about 25 kids and adults huddled inside, Starlab, which stands around 10 feet high and 15 feet wide, projected pinpoint star images on its ceiling using fiber optic technology. "It was kind of scary," said Evan George, 6, of Southeast Memphis, who saw it with his brother Caleb, 7. "You could see the moon and the sun and the Milky Way in front of it." Caleb, who talks of being a scientist when he grows up, ticked off the planets he saw, including one you might have missed in school: "Venus and Mercury and Mars and Earth and Eunice." Kids "love it anytime it's up," said Steve Jackson, headmaster at the day school. "I think they like cramming in there a bit more than the lesson. But the lesson is there." Starlab uses interchangeable projection cylinders to show constellations, celestial coordinates and the position of the moon and planets for any given time. The cylinders can also project the heavens as seen by cultures throughout the world, including Egyptian and Native American, and a map of the world. The mobile lab can be used not only for astronomy classes but for teaching mythology, multicultural studies and earth sciences. The $20,000 planetarium was purchased through The Spirit Fund, the school's annual giving program. Inside the dome, science teacher Mary Cheairs used a red arrow, created with a flashlight, to point to a maze of constellations etched across the dome. Occasionally she passed the pointer to the kids, who seemed to find Cassiopeia and the big and little bears faster than many adults. Starlab was created by Dr. Philip Sadler, director of the Science Education Department at the Harvard Smithsonian Center for Astrophysics. CMDS Christ Methodist Day School purchased one about three years ago. The lab is set up about 15 days a year at the day school and next fall it may go on tour. - Barbara Bradley: 529-2370 Copyright (c) 2009 The Commercial Appeal, Memphis, TN Record - 4 DIALOG(R) Watching the night skies, Geoffrey Saunders, Townsville Bulletin (Australia), 1 - ed, p 32, Tuesday, January 27, 2009 Text: ON October 4, 1957 the Soviet Union created history by launching Sputnik 1, the world's first artificial satellite Alan Stephenson, now aged 81, was an original member and one of many who made up the Townsville Moonwatch Group He said everybody expected the Americans to launch the first satellite; as it happened, the Russians stole the march on it much to everybody's consternation "Within a day or so there was a piece in the Townsville Daily Bulletin that Sputnik 1 would be visible from Townsville that evening," Mr Stephenson said.

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