25.4.12

UF participates in nation’s largest science and technology festival


2010 Edition UF's participants, in front of their booth 
 
The University of Florida’s departments of astronomy, mechanical and aerospace engineering, and the Institute of Food & Agricultural Sciences will participate in the USA Science & Engineering Festival in Washington, D.C., Saturday and Sunday.

The theme of the UF booth is “Gators in Space,” where displays and interactive activities will be used to explain how astronomy and engineering allow a better understanding of the universe and life on Earth.

At the UF booth, Expo visitors will have the opportunity to build their own working telescopes, experience the physical principles needed to control a spacecraft, and handle samples of simulated Lunar and Martian regolith (planetary “soil”) and the palm-sized plant system launched to the International Space Station.

Static and dynamic displays will show how the university is using cutting-edge science and technology to provide solutions to challenges that the world is facing. The booth will have displays of the hardware used for the exploration of space: SwampSat, the first 4-inch-cubed satellite designed and built at UF; a scale model of the Gran Telescopio Canarias, the world’s largest telescope, used by UF astronomers for their research; an orbital plant growth facility and a clinostat (ground-based hardware used to disrupt the effect of gravity sensing in biology). Students and researchers will be available to demonstrate and discuss each of these items.

The USA Science & Engineering Festival is the country’s only national science festival. Its aim is to increase the public’s awareness of the importance of science and to encourage youths to pursue careers in science and engineering. The fair is a month-long celebration, culminating in a two-day exposition including 100 live performances and 3,000 different hands-on activities by more than 500 of the nation’s leading science and engineering organizations. It is free and open to the public.

“The previous Expo held in October of 2010 was a celebration of science; we had many visitors attending the UF booth, including a number of UF alumni. They were very impressed with the kinds of science and engineering projects that were coming out of their alma mater,” said Ata Sarajedini, professor of astronomy who is the overall coordinator of the UF group.

“We have created an official twitter @GatorsinSpace so people can follow all of our activities,” said Dante Buckley, a participating UF engineering doctoral student who is also a member of professor Norman Fitz-Coy’s SwampSat team.

Eric Schultz, an IFAS doctoral student in the space biology program of Robert Ferl and Anna-Lisa Paul, is excited about the opportunity to show visitors advances in biological research in space, “This is a great opportunity to promote interest in the biological sciences and to educate the public about the benefits of astrobiology and extraterrestrial research in general,” Schultz said.

The following video was aired by the local news, before last expo's edition.



The participation of UF at this festival has been made possible by the UF provost’s office, department of astronomy, Florida Space Grant Consortium, the College of Liberal Arts and Sciences, the College of Engineering, the College of Agricultural and Life Sciences and Institute of Food and Agricultural Sciences and the Office of Admissions.

12.4.12

UF-led team use new observatory to characterize low-mass planets orbiting a nearby star


Published in University of Florida News on Thursday, April 9, 2012.

The narrow dust ring around Fomalhaut. Yellow at top is the ALMA image, and the blue at bottom is Hubble Space Telescope image. The star is at the location of the bright emission at the center of the ring.

CREDIT: A.C. Boley (University of Florida, Sagan Fellow), M.J. Payne, E.B. Ford, M. Shabran (UF), S. Corder (North American ALMA Science Center, NRAO), and W. Dent (ALMA, Chile), NRAO/AUI/NSF; NASA, ESA, P. Kalas, J. Graham, E. Chiang, E. Kite (UC, Berkeley), M. Clampin (NASA Goddard Space Flight Center), M. Fitzgerald (Lawrence Livermore National Laboratory), and K. Stapelfeldt and J. Krist (NASA Jet Propulsion Laboratory).


University of Florida astronomers have found compelling evidence for two low-mass planets orbiting the nearby star Fomalhaut, just 25 light years from Earth.

Twice as massive as the sun and 20 times brighter, Fomalhaut is surrounded by a ring of dust and debris, making it a favorite system for astronomers to study and a natural laboratory for testing planet formation theories.

In 2008, images of Fomalhaut taken by the Hubble Space Telescope led to the discovery of “Fomalhaut b,” the first extrasolar planet to be directly detected in visible light. At the time, astronomers believed it to be a giant planet, akin to Jupiter or Saturn, but later infrared images failed to detect the planet, meaning that it had to be smaller than Saturn.

UF astronomers, along with scientists from the new Atacama Large Millimeter Array in Chile, known as ALMA, and the National Radio Astronomy Observatory, used ALMA’s superior resolution and sensitivity to study the system in unprecedented detail. Their results indicate that there are not one, but two planets, with masses between that of Mars and a few times larger than Earth, working together to shape the ring of dust.

The new study reveals that the ring is sharply truncated in the inner and outer edges and is only about 16 astronomical units, or AU, wide, or about 16 times the distance between the Earth and the sun. That may seem large, but the center of the ring is about 140 AU, making the ring relatively very narrow. It also finds that the ring is vertically thin, about one-seventh as tall as it is wide. Those properties give important clues to explain the planetary system of Fomalhaut.

The results are described in a paper to appear this month in the Astrophysical Journal Letters.

“Combining ALMA observations of the ring’s shape with computer models, we can place very tight limits on the mass and orbit of any planet near the ring.” said Aaron Boley, a Sagan Postdoctoral Fellow at UF and leader of the study. “The masses of the planets must be small so they do not destroy the ring, but their masses cannot be too low or they would not shape the ring.”

Although Fomalhaut is a much hotter star than the sun, the planets are so far from their host star that they are among the coldest planets known around a normal star. They are thought to be low-mass bodies, but astronomers do not have enough data to tell whether they have a significant amount of hydrogen gas or are mostly rock and ice.

“ALMA observations show that Fomalhaut’s ring is even more narrow and thinner than previously known,” said Matthew Payne, an astronomer at the University of Florida who contributed to the study. “Fomalhaut b alone only explains the ring's sharp inner edge. Our analysis suggests that two planets, one interior and one exterior, are shepherding the ring, analogous to how Uranus’ moons Cordelia and Ophelia confine Uranus’ brightest ring.”

Credit: ALMA (ESO/NAOJ/NRAO). Visible light image: the NASA/ESA Hubble Space Telescope A. Fujii/Digitized Sky Survey 2. Acknowledgment: Davide De Martin (ESA/Hubble). Music: John Dyson (from the album Moonwind).

The Atacama Large Millimeter/submillimeter Array, located in the Atacama desert of northern Chile at an altitude of 16,400 feet is the largest astronomical project in existence. Still under construction, ALMA began scientific operations in September.

“ALMA may still be under construction, but it has already proved to be the world’s most powerful telescope for observing the universe at millimeter and submillimeter wavelengths of light.” said Stuartt Corder, an astronomer at the National Radio Astronomy Observatory and co-author of the study.

“Once ALMA is completed, we will be able to study systems like Fomalhaut with even greater detail, and see through the veil of dust that hides the early stages of planet formation,” said co-author Bill Dent, an astronomer at ALMA.

This research was supported by the NASA Sagan Fellowship Program, the National Radio Astronomy Student Observing Support Program and the University of Florida's College of Liberal Arts and Sciences. The Joint ALMA Observatory is a partnership of the European Organization for Astronomical Research in the Southern Hemisphere, the National Astronomical Observatory of Japan (on behalf of the National Institutes of Natural Sciences and Academia Sinica), and the NRAO (managed by Associated Universities, Inc. on behalf of the NSF and the National Research Council of Canada) in cooperation with the Republic of Chile.