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Na Kilo Hoku IFA Home Page | Search | Other Editions No. 48 - 2013 From the Director Highlights Gas-Giant Exoplanets The Institute for Astronomy is not immune to the budgetary Cling to Their Parent challenges of the University of Hawai‘i as a whole. In recent years, Stars the state legislature has cut the appropriations for UH. The university had to pass on these cuts to the colleges, departments, and research Study Finds Most institutes. For this fiscal year, which began July 1, IfA has to cope Centaurs Are with a budget reduction of $320,000. This reduction, together with “Cometary” union salary increases and other costs, impacts IfA’s budget by over $500,000. That’s the bad news. Upcoming Events Günther Hasinger The good news is that NASA has finally awarded funds to support Tuesday, October 29, Frontiers the completion of the second Pan-STARRS telescope, which of Astronomy Community All Articles together with the generous private donation we received at the end Event, Nicholas McConnell, IfA of last year will allow PS2 to start operations soon. We very much Beatrice Watson Parrent hope that NASA will also provide funds to operate the Pan-STARRS Postdoctoral Fellow, “Monsters Gas-Giant PS1 and PS2 telescopes in the coming years. The highly successful in the Dark: Supermassive Exoplanets Cling to PS1 first science mission, which began in May 2010 and will end in Black Holes and Their Their Parent Stars February 2014, has been supported by the international PS1 Science Destructive Habits,” 7:30 p.m., Study Finds Most Consortium, NASA, and the National Science Foundation. PS1 and UH Mānoa Art Building Centaurs Are PS2 will start the second Pan-STARRS mission in March 2014. Auditorium (room 132). Free “Cometary” Together PS1 and PS2 will be by far the most powerful wide-field Admission (Campus Parking Two IfA Students imaging system in existence and will continue the search for near- $6). Win UH Research Earth asteroids that may pose a threat to our planet. Prizes More Events>> Protecting Earth In the meantime, our own 2.2-meter (88-inch) telescope, one of the from Asteroid oldest telescopes on Mauna Kea, has become our child of sorrow, Impacts with many of the old subsystems slowly dying and needing to be Comet ISON replaced or repaired. We have had to defer maintenance and Update refurbishment of this telescope for many years. Now we hope to New Faculty: obtain some funding from the state and the university for the most Christoph Baranec urgent upgrades. It is our hope that the 2.2-meter will play a central New Faculty: role in our strategy for the future, as a test bed for new detector Jessica Lu development and adaptive optics technology, and also as a reliable Aloha Pat Henry workhorse for scientists and students. We have recently received Upcoming Events good news in this regard: The National Science Foundation will fund Nā Kilo Hōkū Staff a test bed for an advanced, wide-field ground layer AO system for the 2.2-meter telescope. We are also planning several new initiatives for the coming year, and we are hoping to raise funds for them. These include new astronomy and astrophysics undergraduate majors at UH Mānoa that, when combined with the existing UH Hilo program, will make UH one of the leading producers of astronomers in the United States; a replacement for the Hōkū Kea Observatory, a 36-inch telescope on Mauna Kea, that will be used by the undergraduate majors; a partnership status for UH in the Thirty Meter Telescope to be built on Mauna Kea; a small robotic telescope on Haleakalā for K–12 education and outreach; and increased outreach to schools and the public. Your donations to the IfA Advancement Fund of the UH Foundation can make these plans a reality. If you would like to hear more about http://www2.ifa.hawaii.edu/newsletters/index.cfm?n=53[10/1/13 9:35:00 AM] Na Kilo Hoku these opportunities, please contact our outreach coordinator, Dr. Roy Gal at [email protected]. This newsletter is available in pdf format. Use “shrink to fit” or “shrink to printable area” setting for printer. Follow us Comet ISON Viewing IfA will sponsor viewing opportunities on O‘ahu just before sunrise in late November at a location on the windward side. For exact times and places, check the IfA website, or our Facebook page or Twitter feed (UHIfA). To get on our special events mailing list, send an email to [email protected]. For events on Hawai‘i island, see the website of the Mauna Kea Astronomy Outreach Committee. http://www2.ifa.hawaii.edu/newsletters/index.cfm?n=53[10/1/13 9:35:00 AM] No. 48 - 2013: Gas-Giant Exoplanets Cling to Their Parent Stars IFA Home Page | Search | Other Editions No. 48 - 2013 All Articles Front Page Gas-Giant Exoplanets Cling to Their Parent Stars Gas-Giant Exoplanets Cling to Their Parent Stars Study Finds Most Centaurs Are “Cometary” Two IfA Students Win UH Research Prizes Protecting Earth from Asteroid Impacts Comet ISON Update New Faculty: Christoph Baranec New Faculty: Jessica Lu Aloha Pat Henry Upcoming Events Nā Kilo Hōkū Staff Artist’s rendering of an exoplanet system with a gas-giant planet orbiting close to a star that is more massive than our Sun. Artwork by Lynette Cook courtesy Gemini Observatory/AURA. In 2008, astronomers using the Gemini North telescope and W. M. Keck Observatory on Mauna Kea took the first-ever direct images of a family of planets around the star HR 8799. They found gas-giant planets at large orbital separations (about 25–70 times the Earth–Sun distance). This discovery, made after examining only a few stars, suggested such large-separation gas giants could be common. However, more recent Gemini results, from a much more extensive imaging search, show that gas-giant planets at such distances are in fact uncommon. Results from Gemini Observatory’s recently completed Planet-Finding Campaign—the deepest, most extensive direct-imaging survey to date—show that the vast outlying orbital space around many types of stars is largely devoid of gas-giant planets. “It seems that gas-giant exoplanets are like clinging offspring,” says IfA astronomer Michael Liu, the leader of the campaign. “Most tend to shun orbital zones far from their parents. In our search, we could have found gas giants beyond orbital distances corresponding to Uranus and Neptune in our own solar system, but we didn’t find any.” The campaign was conducted at the Gemini South telescope in Chile, with funding from the National Science Foundation and NASA. The results will help scientists better understand how gas-giant planets form, as the orbital distances of planets are a key signature that astronomers use to test exoplanet formation theories. IfA postdoctoral researcher Eric Nielsen, the first author on the paper about the campaign’s search for planets around stars more massive than the Sun, adds that the findings have implications beyond the specific stars imaged by the team. “The two largest planets in our solar system, Jupiter and Saturn, are huddled close to our Sun, within 10 times the distance between the Earth and Sun. We found that this lack of gas-giant planets in more distant orbits is typical for nearby stars over a wide range of masses.” The campaign revealed similar tendencies around other classes of stars. Liu summed it up this way: “We’ve known for nearly 20 years that gas-giant planets exist around other stars, at least orbiting close- in. Thanks to leaps in direct imaging methods, we can now learn how far away planets can typically http://www2.ifa.hawaii.edu/newsletters/article.cfm?a=657&n=53[10/1/13 9:35:34 AM] No. 48 - 2013: Gas-Giant Exoplanets Cling to Their Parent Stars reside. The answer is that they usually avoid significant areas of real estate around their host stars. The early findings, like HR 8799, probably skewed our perceptions.” A second paper by the team explores systems where dust disks around young stars show holes, which astronomers have long suspected are cleared by the gravitational force of orbiting planets. “It appears that instead of massive planets, smaller planets that we can’t detect directly could be responsible,” said Zahed Wahhaj (formerly a postdoctoral researcher at IfA and now with the European Southern Observatory), the lead author on the survey’s paper on dusty disk stars. Finally, the team’s third new paper looks at the very youngest stars close to Earth. “A younger system should have brighter, easier to detect planets,” according to the lead author Beth Biller, a former IfA postdoctoral researcher who is now at the Royal Observatory Edinburgh. “Around other stars, NASA’s Kepler telescope has shown that planets larger than the Earth and within the orbit of Mercury are plentiful,” Biller explained. “The NICI Campaign demonstrates that gas-giant planets beyond the distance of the orbit of Neptune are rare.” The observations for the campaign were obtained with the Gemini instrument known as NICI, the Near- Infrared Coronagraphic Imager, the first instrument for an 8–10 meter-class telescope designed specifically for finding faint companions around bright stars. Doug Toomey of Mauna Kea Infrared and the IfA’s Christ Ftaclas and Mark Chun built NICI with funding from NASA. A new instrument, the soon-to-be-delivered Gemini Planet Imager, will likely reveal whether giant planets in orbits similar to the gas-giant planets of our own solar system are common. http://www2.ifa.hawaii.edu/newsletters/article.cfm?a=657&n=53[10/1/13 9:35:34 AM] No.