ASTR OR ON F O E M T No. 37 • 2010 Y U T I T S A Newsletter from the N I Institute for Astronomy U n ‘ i i i ve a Na¯ Kilo Ho¯ku¯ w University of Hawai‘i rsit f Ha THE ONES WHO LOOK TO THE STARS y o Hasinger New IfA Director Günther Hasinger, whose work has been instrumental in the operation of X-ray satellites and the development of future observatories, has been appointed director of the Institute for Astronomy, effective January 2, 2011. Hasinger is currently the scientific director at the Max Planck Institute for Plasma Physics (IPP) in Garching, near Munich, Germany. His work there focused on the synergies between astrophysics and plasma physics—introducing modern X-ray diagnostics into fusion physics, with the aim of reproducing the Sun’s source of energy in a fusion power plant. Hasinger is a world leader in the field of X-ray astronomy and in the study of black holes. Together with his colleagues, he has resolved the cosmic X-ray background radiation into discrete objects, which were then identified mainly as active black holes in distant galaxies. These studies showed that the cosmological evolution of active galactic nuclei (the centers of galaxies that emit much more radiation than can be produced by stars alone) is closely associated with the star-forming history of SLACS strong lens object galaxies in the Universe and that black holes are likely motors for the SDSSJ1430 development of galaxies. Hasinger received his physics diploma from Ludwig Maximilian University (LMU) in Munich, and a PhD in astronomy from LMU for research done at the Max Planck Institute for Extraterrestrial Physics (MPE). He served as director of the Astrophysical See Hasinger, pg 3 EPOXI: Deep Impact, Part 2 What’s Inside by Louise Good Remember the Deep Impact mission? In July 2005, the Solar Eclipse 2010 pg 2 Deep Impact spacecraft left an impactor in the path of Comet Tempel 1 so that the two would collide, Masursky Award pg 3 enabling scientists to see the inside of a comet. The HI STAR pg 4 impactor was, of course, destroyed, but the main part of the spacecraft continued to function well, and Faculty Profile pg 5 NASA, not wishing to waste a perfectly good Are We Alone? pg 6 spacecraft, gave it a new mission. 2011 IfA Calendar They named this mission EPOXI because it actually Upcoming Events pg 7 was two missions stuck together: EPOCh, the Extrasolar Planet Observation and Characterization pg 8 From the Director investigation, which observed stars with known transiting giant planets from January to August 2008, The EPOXI spacecraft took this image of Comet Hartley 2 as it and DIXI, the Deep Impact eXtended Investigation of flew by the comet around 3:59 a.m. HST on November 4 at a comets. The goals of DIXI are to understand how distance of about 435 miles (700 km). Jets can be seen streaming features of a cometary nucleus (the solid part of the out of the nucleus. Photo courtesy NASA. comet) relate to those of the coma (the envelope of gas In the early morning hours of November 4 HST, the and dust around the nucleus), to study the diversity of spacecraft made its closest approach (435 miles/700 cometary nuclei and the heterogeneity within a km) to Comet Hartley 2. It is the smallest comet ever The University of Hawai‘i cometary nucleus, and to learn more about the origin is an Equal Opportunity/ seen close-up, a mere 0.37 miles (0.6 km) in average of the solar system by studying the structure, Affirmative Action Institution. radius, but the nucleus itself is highly elongated, that composition, and formation of cometary nuclei. is, it is long and narrow. Please see EPOXI, pg 7 tons of equipment from Papeete. The liquid nitrogen barely made it to Tatakoto because of a firefighter’s strike in Papeete the week the empty dewars (thermos-like containers) arrived from Honolulu. The dewars were to be filled in time to catch a boat to Tatakoto, but missed the boat by a few hours. Through tactful negotiations, Air Liquide and DHL Danzas (which transported the dewars to Papeete) convinced Air Tahiti to fly the filled dewars to Hao in time to catch up with the boat going to Tatakoto. Eclipse observations provide unique opportunities for exploring the ionized gas, or corona, that forms the extended atmosphere of the Sun. The temperature of this gas exceeds a million degrees, so it is not possible to replicate coronal processes in laboratories. Curiously, the heavier elements, such as iron, nickel, and sulfur, which only constitute a minute fraction of the bulk protons and electrons forming this gas, offer important clues about its behavior and properties, particularly the escaping component known as the solar wind. Fortunately, these ions emit light at well-known wavelengths. By selecting filters centered on these wavelengths, we can explore the behavior of these ions. We imaged the corona in seven spectral lines—five iron lines characteristic of plasma temperatures ranging from half a million to over 2 million degrees Kelvin (3.6 million degrees F), a cool 10,000-degree hydrogen line, and a The 2010 solar eclipse 2010 Solar Eclipse Expedition 3-million-degree nickel line. Spectral measurements were expedition observed five by Shadia Habbal also made with three different spectrographs, and Lin set iron lines (Fe IX, Fe X, Fe up his very ambitious polarization experiment to measure Mounting a solar eclipse expedition requires advance XI, Fe XIII, Fe XIV), one the magnetic field direction and strength in a region of the planning, patience, and optimism. The best options for the hydrogen line (H-alpha), and corona. July 11 eclipse were a few atolls in French Polynesia. We a nickel line (Ni XV). It was The clouds looked rather ominous at 6 a.m. on the needed a usable airstrip and accommodation for 20 people. the first time that the corona morning of the eclipse. Fortunately, the Sun rose above We also needed 100 liters of liquid nitrogen for Haosheng was imaged in Fe IX and Ni them before totality began at 8:47 a.m. Despite the rolling Lin’s polarization experiment. XV. © 2010 Miloslav clouds during the four minutes of totality, imaging Druckmüller, Martin The largest atoll that seemed to fulfill our requirements simultaneously in the spectral lines and their neighboring Dietzel, Shadia Habbal, was Hao. Bed and breakfast manager François Dantzer continuum enabled us to remove the effects of the clouds. Vojtech Rusin assured me that he could find accommodations for us When the images were subtracted from each other, they there. A week later, he contacted me to say that Tatakoto, exposed the pure emission from hydrogen, iron, and nickel. an atoll 745 miles (1,200 km) from Tahiti’s capital, Preliminary results show that there is a very distinct Papeete, would offer a longer eclipse, and it had a landing separation between the solar features seen in the cooler Our group consisted of a strip. He also said that our group could use the local school emission lines and those seen in the hotter ones. Some 12-member IfA team as our staging and observing site, and as sleeping quarters. I solar features were seen in iron lines but not in white light. (including several European contacted the school’s headmaster, Heifara Lanteires, and The explanation is rather simple and neat: Initially, all the collaborators) and an got the ball rolling. ions are linked together, but if there is not enough energy eight-member team from Getting to Tatakoto was a challenge. We had to charter for all of them to escape the solar gravitational field, the Italy. Standing, from left to a plane from Air Tahiti to transport us and our nearly two heavier ions lag behind. right: P. Calcidese, L. Casetti, C. Benna, S. Fineschi, G. Capobianco, V. Rusin, H. Lin, J. Saken, A. Daw, M. Druckmüller, A. Ding. Seated: M. Arndt, F. Trevisan, M. Romoli, G. Massone, G. Nitta, J. Johnson, S. Habbal, M. Dietzel, H. Morgan. 2 Spectroscopy & Science Visible spectrum The spectrum of each chemical element is unique, like the fingerprint of a person. Each color spectral band of an element represents a particular wavelength of light. Spectral bands occur when an electron moves between two energy levels in an Hydrogen atom and emits energy as a photon (a particle of light). Measuring the strength and width of spectral lines allows the composition and physical properties of a substance to be determined. Neon Spectral lines are designated according to the level of ionization by adding a Roman numeral to the symbol of the chemical element. Neutral atoms are denoted by I, singly ionized atoms (those Iron missing one electron) with II, and so on. For example, Fe IX represents an iron atom that is The visible spectrum of light and emission line spectra of hydrogen, neon, and iron. Note that missing eight electrons. the heavier an element is, the more spectral bands it has. Tokunaga Wins Masursky Award The Division for Planetary Sciences of the American Through his research, Tokunaga has made contributions Astronomical Society conferred the 2010 Harold Masursky to planetary science in the areas of the composition of Award on IfA astronomer Alan Tokunaga for his planetary atmospheres, asteroids, and comets. His research outstanding service to planetary science and exploration on has also delved into the composition of the interstellar October 6 at its annual meeting in Pasadena, California. medium and the formation of stars. Tokunaga has served as director of the NASA Infrared He has advanced infrared astronomy by standardizing Telescope Facility on Mauna Kea since 2000, the longest the filters used by various telescopes at infrared term in the history of that observatory.