The Gran Telescopio Canarias, or GTC, under construction in Spain’s Canary Islands for the past seven years, will hold its “first light” opening ceremony Friday. UF, which contributed $5 million to the project and owns a 5 percent share, is the only U.S. institution with a stake in the massive telescope.

“This is one of the largest international projects that the university is involved in, and first light is certainly a big step for a small department,” said Stan Dermott, astronomy department chairman and one of four UF astronomy faculty members who will attend Friday’s ceremony.

The roughly $175 million GTC is not yet complete. Only 12 of the 36 mirrors that together will compose its 34.1-foot primary mirror have been installed, Dermott said. The rest are expected to be mounted this year, with the telescope’s grand opening — to be presided over by King Juan Carlos I of Spain — set for next summer. Only after that date will scientific-quality observations begin.

All that said, enough of the mirror is assembled to allow telescope operators to make initial test runs, he said. So at 10 p.m. Greenwich Mean Time Friday (6 p.m. EDT), Prince Felipe, heir to the Spanish throne, will train the telescope on Polaris, the North Star, for a ceremonial observation to be attended by about 300 people.

Besides Dermott, the UF contingent will be astronomers Charlie Telesco, Rafael Guzman and Anthony Gonzalez, as well as Tom Walsh, UF director of sponsored research. “This will be the first demonstration that the telescope can produce a focused image of a star,” Dermott said.

The Spanish government is the main owner of the GTC, with UF and two institutes in Mexico as partners. As a result of its participation, UF astronomers will be allotted 20 nights of telescope time annually for observations. A UF-designed and built infrared imager and spectrometer, meanwhile, will be one of the first instruments mounted on the telescope when it opens for scientific observation next year.

“We are not just passive partners in this project,” Dermott said. “We are the world’s leader in developing astronomical instruments, and our instrument, CanariCam, will be one of the first instruments used on the GTC.”

Dermott said UF’s participation in the GTC effectively makes it one of a handful of institutions with guaranteed access to the world’s most powerful telescopes. That will open the door to a wide range of research not only at the GTC but elsewhere as well.

”Already we are forming scientific teams that will involve other telescopes to take part in surveys of the distant universe,” he said. “For example, Rafael Guzman is leading a team that will investigate the origin of galaxies. In a sense, we have joined the club of big observers now.”

Funded in part by the Spanish government with a $6.5 million grant, Guzman’s team of 40 astronomers from the U.S., Spain, France and England is conducting a survey called GOYA, or Galaxy Origins and Young Assembly. Other UF astronomers are also participating or heading GTC-related projects.

But University of Florida physicists have proposed a way to do just that, a step they say considerably improves the chance of detecting one of the universe’s most elusive particles, a candidate for the common but mysterious dark matter.

In a paper that appears online today in the journal Physical Review Letters, physicists at the University of Florida and Lawrence Livermore National Laboratory propose a redesign of the experiment currently being attempted in various forms by several groups of physicists worldwide. Although theoretical at the moment, they say their design could make such experiments a billion times more sensitive in their goal of detecting axions.

Axions are elemental particles whose confirmation would shed light on several different conundrums in particle physics. These could include pinning down the nature of dark matter, the mysterious substance said to make up 30 percent of the universe but so far observed only indirectly by its effects.

“A half dozen groups want to do this experiment, and some of them probably will try this approach,” said Pierre Sikivie, a faculty member in UF’s physics department and an author of the paper. “It works in principle, but in reality it will take some effort to set this up right so that it can produce a result.”

The unimproved experiment seeks to detect axions by shining a laser down the bore of a powerful superconducting magnet. A wall in the middle stops the laser cold, with the theoretical axions continuing through the wall and into the other side of the magnet. There, the magnet reconverts them into photons, or particles of light.

The detection of this light “reappearing” on the other side of the wall is what gives the experiment its iconic name.

Researchers in the U.S. and Europe are in various stages of conducting the experiment. The activity has been stimulated by a recent Italian experiment that claims to have discovered axion-like particles. The hope is to confirm the Legnaro National Laboratories’ results or take them a step further.

Sikivie, UF physics professor David Tanner and Karl van Bibber, a physicist at the Lawrence Livermore National Laboratory, propose a redesign of the “shining light through walls” experiment to make it, in their words, “vastly more sensitive.”

In a nutshell, they suggest placing pairs of highly reflective mirrors called Fabry-Perots cavities on both sides of the wall. The cavity on the laser light side of the wall would cause the light to bounce back and forth repeatedly, as though in an echo chamber. This action would produce many more of the hypothesized axions than a single beam of light, making them easier to detect on the other side of the wall.

“What happens is, because the light goes back and forth many times as it goes through the magnet, it produces more axions,” Sikivie said.

The Fabry-Perot cavity on the other side of the wall would perform a similar function, producing even more photons from the added axions.

Sikivie said researchers are doing separate experiments to detect axions produced by the sun, which would seem to be an easier approach because the sun is a much more powerful source than any laser. But the modified experiment would at least in theory have a higher sensitivity than these solar-based experiments.

“With these two cavities on both sides, it actually gets better, by a factor of 10 maybe, than the solar axion experiments,” he said.

A University of Florida astronomer is among more than three dozen astronomers who found the new large planets, announced today at the Transiting Extrasolar Planets Workshop at the Max Planck Institute for Astronomy in Heidelberg, Germany.

Stephen Kane, a UF postdoctoral associate, said he and his colleagues pinpointed the planets by detecting the slight dimming of starlight that occurs when the planets pass in front of their stars. Of about 200 planets discovered so far, the new planets are only the 13th and 14th to be found using this technique, called the transit method. But that’s likely to change quickly as the United Kingdom-based effort to discover planets with the transit method gathers steam, Kane said.

“We can expect these two planets to be the first in a wave of a whole lot of these new types of planets,” he said.

Known as “Hot Jupiters” because of their Jupiter-like size and temperature, the new planets are so close to their stars that they complete their orbit in a mere two and two-and-one-half days, respectively. That compares to 88 days for Mercury, the planet with the fastest orbit nearest the sun in our solar system. The very close orbit also means that the new planets are hotter than Mercury, which has a surface temperature of 752 degrees Fahrenheit. The planets are estimated to have a temperature of at least 3,272 degrees.

There is also evidence that the solar radiation from the stars is so intense that it is whipping away their atmospheres. “Hot Jupiters are assumed to have a significantly reduced lifetime due to their proximity to the star,” Kane said.

Most planets outside our solar system have been found using the radial velocity method, which measures the gravitational wobble in the star induced by the orbiting planet. The transit method would seem at first to be impractical because it requires a lucky break: The orbital plane of the planets under observation must be aligned toward Earth so astronomers can see the starlight dim as the planets pass.

The astronomers who discovered the two new planets dealt with this complication through, in Kane’s words, “brute force.” The astronomers surveyed millions of stars using twin telescopes snapping photos of the southern and northern skies from La Palma in Spain’s Canary Islands and Sutherland, South Africa. Each telescope is equipped with eight wide-angle cameras, each of which has a field of view of eight degrees, which comprises a relatively large chunk of the sky. By comparison, the full moon comprises about half a degree.

The work was done through UK’s leading planet detection program, a consortium of eight universities called SuperWASP, or Wide Angle Search for Planets.

Kane’s role in the research was to help pick out from the vast numbers of photographed stars the most likely candidates for further investigation. The job was a difficult one because planets passing in front of stars only slightly diminish the starlight, dimming it by only about 1 percent for just a few hours. Kane also led the research on the prototype for SuperWASP, and has worked on both SuperWASP telescopes, among other efforts.

“We have computer programs which are able to search all of these light curves from the stars and see if there’s something in them which looks like the star has become fainter for a short period, but it’s a complicated task,” Kane said.

After SuperWASP identified the tiny dips in starlight caused when the planets passed in front of their stars, a French-built instrument detected a slight wobble in each star’s motion as the planets passed around them, confirming the existence of the planets.

The planets are located in the constellations Andromeda and Delphinius, respectively. The Andromeda planet is more than 1,000 light years away, while the Delphinius planet is 500 light years away.

Both of the new planets are far too hot to support life. But Kane said their discovery adds to growing knowledge about how planets form, which should help astronomers understand and zero in on Earth-like planets.

“Once we understand planet formation, we’ll understand a lot more about how terrestrial planets form as well,” he said.

Source
Stephen Kane, skane@astro.ufl.edu, at conference in Germany:
(011) 49-6221-9130, Room 422

“It’s the most direct evidence that we have for dark matter,” said Anthony Gonzalez, an assistant professor of astronomy at the University of Florida and a member of the team of astronomers who made the discovery. “You can actually see the separation between where the bulk of the matter is and the normal everyday matter.”

These results are being published in an upcoming issue of The Astrophysical Journal Letters. The discovery was made with NASA’s Chandra X-ray Observatory and other telescopes.

Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it is stronger on intergalactic scales than predicted by Newton and Einstein, removing the need for dark matter. However, such theories cannot explain the observed effects of this collision.

“A universe that’s dominated by dark stuff seems preposterous, so we wanted to test whether there were any basic flaws in our thinking,” said Doug Clowe of the University of Arizona at Tucson, leader of the study. “These results prove that dark matter exists.”

Gonzalez echoed Clowe, characterizing the results as raising a “significant challenge” to dark matter alternative theories.

In galaxy clusters, the “normal” matter, like the atoms that make up the stars, planets and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. The galaxies and hot gas are bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and currently can be detected only through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart.

The team used about a week of Chandra time to observe the galaxy cluster 1E0657-556, which is also known as the “bullet cluster” because of a spectacular bullet-shaped cloud of extremely hot gas. The X-ray image shows that the bullet shape is due to a wind produced by the high-speed collision of a smaller cluster with a larger one.

Meanwhile, the Hubble Space Telescope, European Southern Observatory’s Very Large Telescope and Magellan optical telescopes were used to determine the location of the mass in the clusters. This was done using a technique known as gravitational lensing, where gravity from the clusters distorts light from background galaxies as predicted by Einstein’s theory of general relativity.

Gonzalez assisted in the analysis of the Hubble Space Telescope images and otherwise contributed to the optical data analysis.

The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact because it does not interact directly with itself or the gas except through gravity. This produced the separation of the dark and normal matter seen in the data. If hot gas were the most massive component in the clusters, as proposed by alternative gravity theories, such a separation would not be seen. Instead, dark matter is required.

“This is the type of result that future theories will have to take into account,” said Sean Carroll, a cosmologist who was not involved with the study. “As we move forward to understand the true nature of dark matter, this new result will be impossible to ignore.”

This result also gives scientists more confidence that the Newtonian gravity familiar on Earth and in the solar system also works on the huge scales of galaxy clusters.

“We’ve closed this loophole about gravity, and we’ve come closer than ever to seeing this invisible matter,” said Clowe.

NASA’s Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency’s Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center, Cambridge, Mass.

Additional information and images can be found at: http://chandra.harvard.edu and http://chandra.nasa.gov.

Other scientists involved in the research include Marusa Bradac of the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC); Dennis Zaritsky of the University of Arizona’s Steward Observatory; Maxim Markevitch, Scott Randall, Christine Jones and William Forman of the Harvard-Smithsonian Center for Astrophysics, Tim Schrabback of the University of Bonn, and Phil Marshall of KIPAC. Support for this work was provided by the National Science Foundation and NASA. This project was also partially supported by the Department of Energy through the Stanford Linear Accelerator Center.

GAINESVILLE, Fla. — Astronomers from Spain, Mexico and the United States will gather in Miami next week to plan for the first observations of the world’s largest telescope – a $160 million behemoth under development for the past six years on Spain’s Canary Islands.

As many as 150 astronomers from the partner institutions in the Gran Telescopio Canarias or GTC – the University of Florida, two universities in Mexico and several Spanish institutions — will meet in Coral Gables starting Tuesday to plan the telescope’s first observations, expected late next year.

The highlight of the weeklong “First Light Science with the GTC” conference will be a reception, to be attended by UF President Bernie Machen, U.S. and Mexican officials and astronomers, Thursday evening at the Biltmore Hotel in Coral Gables.

Members of the media are invited to the event, which will feature speeches and presentations by Machen and other dignitaries, as well as leading astronomers. There will also be a detailed scale model of the GTC on display, as well as a live video tour of the telescope on the Canary Islands off Africa’s west coast.

A 5 p.m. lecture on the history of astronomy in Spain and the Americas will precede the cocktail reception, which begins at 6 p.m. Presentations and the guided video tour will follow from 7 to 8 p.m. The Biltmore is at 1200 Anastasia Ave., Coral Gables.

When the GTC is completed, the telescope will have a 10.4 meter, or 34.1 foot, primary mirror, the largest mirror of any optical telescope in the world. That will give it unprecedented power to peer into the heavens — the equivalent of the ability to see the edge of a dime from two miles away, said UF astronomy professor Charlie Telesco. That means the telescope will be able to spot both extremely faint objects, such as dim planets orbiting bright stars, and very distant ones, such as galaxies millions of light years away.

Because of the time it takes for light to travel, the most distant objects are also the oldest, and the GTC will be able to peer back to when the 13-billion-year old universe was just 7 percent of its current age, or 900 million years old, Telesco said. That will significantly enhance astronomer’s understanding of the origins of galaxies, stars and planets, he said.

“When we add all the pieces together, we can weave a fabric that can begin to describe the universe,” he said.

The Universidad Nacional Autónoma de México and the Instituto Nacional de Astrofísica, Óptica y Electrónica in Mexico, as well as the Instituto de Astrofisca de Canarias in Spain, are among the GTC’s other partners. The international element is important because it represents a unique opportunity for Florida to build a top telescope program, said Stan Dermott, professor and chairman of the UF astronomy department.

“A single university like UF does not have the financial resources to build a giant telescope or the complex instruments that go with it on its own,” Dermott said. “We can only participate in world-class astronomy and space science through collaboration.”

Dermott noted that the GTC endeavor represents a renewal of ties between countries with traditions in astronomy. Spain was a leading center of astronomy in the era leading up Columbus. Indeed, Spanish astronomers warned Columbus that his estimate of the distance to India was far too low, a warning that proved correct when he stumbled on America en route, said Steve Eikenberry, a UF astronomer. Meanwhile, indigenous people in pre-Columbian Mexico were finely attuned to astronomical calendars and events, he said.

“The Maya in particular in Mexico had very advanced astronomical science,” Eikenberry said. “They built their cities around astronomical orientations and had accurate calendars.”

He and UF astronomy Professor Rafael Guzman will cover that and other elements of the history of Hispanic astronomy leading up to the GTC in their lecture Thursday prior to the reception. “There are significant historical roots for the GTC project,” Eikenberry said. “Today, Hispanic astronomy is seeing a tremendous upsurge and the University of Florida is very much at the epicenter of a lot of that activity.”

Besides the participants, sponsors of the conference include the National Science Foundation, the Greater Miami Convention & Visitors Bureau, the Canary Islands Foundation and Schott, the manufacturer of the glass used in the mirror.

En Español:
Astronomos se reunen en Miami en torno al telescopio mas grande del mundo

The team of astronomers from the University of Florida, NASA’s Jet Propulsion Laboratory and the Lawrence Livermore National Laboratory has found nearly 300 new galaxy clusters and groups, including nearly 100 at distances of eight to 10 billion light years. The new sample, a six-fold increase in the number of known clusters and groups at such extreme distances, will allow astronomers to study very young galaxies two-thirds of the way back to when the universe is believed to have originated in the Big Bang.

The team will present its findings today in Calgary, Canada, at the American Astronomical Society’s biannual meeting.

Anthony Gonzalez, an assistant professor of astronomy at UF and one of the team of astronomers who made the discovery, likened the view of the clusters to a glimpse at the Los Angeles basin when it was still home only to a collection of dusty, small towns. By knowing what the clusters looked like eight to 10 billion years ago, the astronomers will have a better idea of where and when the first stars and galaxies formed and how they grew and changed over the universe’s full 13.7 billion- year lifespan.

“It would be like taking a snapshot of cities as they were near the beginning,” he said. “You’re watching everything fall together, so you can see some of the pieces, some of the little towns, before they become part of a giant city.”

Galaxy clusters are among the universe’s most dense places, similar to cities on Earth, and a single galaxy cluster can contain hundreds of large galaxies similar to our Milky Way.

The most massive, oldest galaxies tend to be found in galaxy clusters. This makes clusters the best place to look to determine when the first stars formed and how these galaxies grew with time. While individual galaxy clusters have previously been found at similar distances, this is the first time that such a large number of galaxy clusters has been detected so far away.

Gonzalez said the astronomers’ key step in finding the large number of clusters was to merge infrared data from NASA’s Spitzer Space telescope with existing deep optical imaging obtained by National Optical Astronomy Observatory Deep Wide-Field Survey team at Kitt Peak National Observatory in Arizona.

The team used the Spitzer telescope to make infrared mosaics, a process that was thousands of times faster than with the biggest ground-based telescopes because of the Spitzer telescope’s unique capabilities. The combined Kitt Peak and Spitzer data provided information on the distances to the galaxies, enabling the astronomers to weed out small, nearby galaxies whose light was cluttering the view between the observers and the most distant clusters. Gonzalez’s main role was to analyze the maps of massive galaxies and detect the hidden galaxy clusters.

“We’re basically getting rid of all the junk to isolate the most distant, massive galaxies,” Gonzalez said.

The research will allow astronomers to embark on several new studies, said Mark Brodwin, an astronomer at the Jet Propulsion Laboratory and a co-investigator on the team.

“Clusters of galaxies are the repositories of the most massive galaxies in the universe,” he said. “As such, our survey serves as an ideal laboratory in which to study the process of massive galaxy formation over the last two-thirds of the lifetime of the universe.”

The next step is to study the newly discovered galaxies in detail, Brodwin said. Astronomers want to learn more about their size, shape, mass and the rate at which they form new stars and merge together to form larger galaxies. “These key measurements will improve our fundamental understanding of the galaxy formation process,” he said.

NASA’s Jet Propulsion Laboratory, based in Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. JPL is a division of Caltech.

Researchers, including a University of Florida astronomer, found the planet, which has a mass about five times that of Earth, orbiting a small star near the center of the galaxy in the constellation Sagittarius.

Located about three times as far away from its star as the distance from Earth to the sun, it is probably too cold to support life. But its presence suggests there are many other small planets orbiting the star. That makes it likely that at least some are located in the so-called habitable zone, the region around stars where temperatures are moderate enough for liquid water to appear on their surfaces.

“The good thing about this is it shows that planets this size might be quite common in habitable zones,” said Stephen Kane, a postdoctoral associate in UF’s astronomy department.

Kane co-authored a paper about the discovery set to appear Jan. 26 in the journal Nature.

Since the first planet was discovered outside our solar system in 1992, astronomers have found the vast majority of the 160-plus planets so far with a technique called radial velocity. The technique detects planets that are too faint to be seen with visual telescopes by observing the wobble in the stars induced by the orbiting planet.

Bigger planets have more gravitational pull, inducing bigger, more detectable wobbles. Also, the closer planets lie to the star, the more wobble they cause. As a result, radial velocity tends to turn up the largest, closest, hottest and consequently the most gaseous planets – planets, in other words, that are not good candidates for supporting life.

Astronomers discovered the new, small planet by tapping a completely different stellar phenomenon: galactic microlensing. Most easily observed with small, older stars known as M dwarfs, microlensing occurs when light from a distant star encounters the gravitational field of a closer star as the closer star passes in front or just to the side it. The gravitational field literally bends and magnifies the light.

The effect is a bit like the beam from a searchlight encountering a giant magnifying glass. But, for planet-finders, the key item of interest is that if the parent star is orbited by a planet, the planet’s gravitational field also acts as its own little lens — magnifying some of the distant star’s light in a brief but distinctive flicker.

“There’s a very subtle effect, a spike, and that’s what we’re looking for,” Kane said.

It’s rare for one star to pass so near another star that it causes microlensing to occur. The timing is also brief, with most microlensing events lasting 30 days or less. As a result, astronomers hunting such events focus their searches on the center of the galaxy, where stars are most densely distributed. This area is best viewed from the Southern Hemisphere, so astronomers coordinate observations using multiple telescopes in such places as Australia, Chile, South Africa and the Canary Islands.

“We have a real-time alert system,” Kane said. “We’ve got people in Australia observing, and if they see something strange happen but their source is starting to set, they call up South Africa and say, ‘Something’s happening here. Point your telescopes at this.’”

In the latest finding, some 73 astronomers affiliated with three independent groups coordinated observations of a microlensing event first identified on July 11, 2005. Nearly a month later, on Aug. 9, the astronomers observed “a short duration deviation from a single-lens light curve … due to a low-mass planet orbiting the lens star,” the Nature paper says.

The planet is at the outer edge of the zone where it can be seen. With a surface temperature below 350 degrees below zero, it is probably rocky and icy. Even if conditions appeared more favorable for life, its location would make it tough to learn more: The planet is located 7,000 parsecs, or nearly 23,000 light years, from Earth.

That said, M dwarfs are the most common type of stars in the galaxy. The fact that microlensing uncovered such a small planet around one M dwarf suggests that there are likely many others, possibly with better conditions, Kane said.

“This has huge implications for finding life,” he said.

The feat suggests that astronomers have found a way to dramatically accelerate the pace of the hunt for planets outside our solar system.

“In the last two decades, astronomers have searched about 3,000 stars for new planets,” said Jian Ge, a professor of astronomy at the University of Florida. “Our success with this new instrument shows that we will soon be able to search stars much more quickly and cheaply – perhaps as many as a couple of hundred thousand stars in the next two decades.”

Ge and colleagues at the University of Florida, Tennessee State University, the Institute of Astrophysics in Spain’s Canary Islands, Pennsylvania State University and the University of Texas presented their findings today at the American Astronomical Society’s annual meeting in Washington, D.C.

Their work is important in part because of what the astronomers found – a planet, at least half as massive as Jupiter, orbiting a star just 600 million years old. That’s very young compared, for example, with the sun’s 5 billion years.

“This is one of the youngest stars ever identified with a planetary companion,” Ge said. Perhaps more significant, the instrument used to find the planet points the way to a much more accessible method for finding others — including those capable of supporting life.

Planets outside our solar system are typically swamped by the light of their stars, making it difficult to observe them visually. In the 1990s, astronomers began using a measurement technique called Doppler radial velocity to detect planets by observing the wobble in a star that is gravitationally induced by an orbiting planet.

This technique, which has uncovered the vast majority of the 160-plus extrasolar planets found so far, works by hunting through the spectrum of starlight for the subtle Doppler shifts that occur as the star and planet move toward and away from their common center of mass. The instrument at the heart of this technique is usually a spectrograph, but this instrument is problematic.

“A major problem with spectrographs is that they collect only a small percentage of photons from the target light source, which means that they are only useful to search for distant planets when mounted on relatively large telescopes,” Ge said.

The astronomers’ new instrument, the Exoplanet Tracker, or ET, eliminates this problem by swapping the spectrograph with an interferometer, a device that can take more precise radial velocity measurements. Tests show the interferometer can capture as much as 20 percent of available photons, making the instrument far more powerful, which opens its use for distant planet hunting to smaller telescopes.

At a development cost of about $200,000, the interferometer-equipped ET is also far cheaper than comparable spectrographs, which cost more than $1 million. And at about 4 feet long, 2 feet wide and weighing about 150 pounds, it is lighter and smaller. The instrument is based on a concept first proposed in 1997 by Lawrence Livermore National Lab physicist David Erskine.

The astronomers used the Exoplanet Tracker on the special 0.9-meter Coudé feed system within the National Science Foundation’s 2.1-meter telescope at Kitt Peak National Observatory near Tucson, Ariz.

Like radial velocity instruments equipped with spectrographs, the ET instrument in its present form can search only one object at a time. But Ge’s team has demonstrated that it can hunt for planets around multiple stars simultaneously – a key element of its heightened utility. The team is working on a version capable of surveying as many as 100 stars simultaneously.

The Exoplanet Tracker will be used next spring for a trial planet survey on the Sloan Digital Sky Survey 2.5 meter wide-field telescope at the Apache Point Observatory in New Mexico. The new instrument is funded with an $875,000 grant from the W.M. Keck Foundation. A much more ambitious, long-term survey is in the planning stages.

The Kitt Peak Coudé feed telescope that Ge and colleagues used to discover the new planet has a 0.9-meter mirror on a tall tower, a mirror that directs incoming starlight into an observing room in the base of the 2.1-meter telescope. The standard spectrograph in the facility fills the room — while ET occupies a small corner.

The new planet is the most distant ever found using the Doppler technique with a telescope mirror less than 1 meter in size. There are hundreds of such telescopes worldwide, compared with just a handful of the larger 2- and 3-meter telescopes more commonly used in planet finding – telescopes that tend to be in extremely high demand and difficult to access.

“These smaller telescopes are relatively cheap and relatively available,” Ge said, “so you can often get access to many dozens of nights on them if you have a promising proposal.”

Kitt Peak National Observatory is part of the National Optical Astronomy Observatory, Tucson, Ariz., which is operated by the Association of Universities for Research in Astronomy Inc., under a cooperative agreement with the National Science Foundation.

“This is the first time that a planet has been discovered using a publicly funded telescope at the U.S. national observatory,” said Buell Jannuzi, acting director of Kitt Peak National Observatory. “We are very excited that the broader community of astronomers around the world will be able to propose to use the single-object Exoplanet Tracker instrument at Kitt Peak to carry out their own research programs, starting in the fall of 2006.”

That said, discovering new planets is never easy.

In the latest find, astronomers went to great lengths to ensure they were actually “seeing” a planet. That’s because the star, which has about 80 percent of the mass of our sun, retains much of its youthful rotation speed, which makes it capable of generating strong magnetic fields and associated dark star spots. These are similar to the magnetically generated sunspots on our own sun, and they can mimic the presence of a planet in orbit around the star.

To check against this possibility, Greg Henry, an astronomer at Tennessee State, observed the star with an automated telescope in Arizona, and found the star to be changing its brightness as it rotates.

“My observations reveal a rotation period of about 12 days for the star,” Henry said. “Thus, if the planetary orbital period is indeed less than five days, the dark spots rotating around on the surface of the star every 12 days cannot be causing the false appearance of a planet.”

Located in the direction of the constellation Virgo, the newly discovered planet completes its orbit in less than five days, meaning it orbits very close to its parent star and is very hot. That means it’s too close to the star to lie within the “habitable zone” where life is possible.

Relying on observations from the Gemini South telescope in Chile, the University of Florida-led team has concluded that differences in brightness in the dust disc surrounding a star known as Beta Pictoris stem from an extra bright clump on one side of the disc. This clump, the astronomers say, is composed of dust particles that are consistently smaller than particles elsewhere in the disc – likely evidence of a collision of two massive asteroids or tiny developing planets known as planetismals that may have occurred as recently as in the past few decades.

An article about the discovery is set to appear Jan. 13 in the journal Nature.

“What we’re proposing is that a planetesimal – either a very small planet or a very large asteroid — has collided with another similar object and has been catastrophically destroyed,” said Charlie Telesco, a UF astronomy professor and the paper’s lead author. “It’s a cloud now, but what we’re proposing is that this cloud represents the debris of a major collision.”

The findings are of interest because they suggest a new explanation for a phenomenon — asymmetries or lopsided appearances in star dust discs — that has long puzzled astronomers, Telesco said. The results also continue to help refine the evolving science of planet-finding, an endeavor that has turned up more than 100 planets outside our solar system since the first was discovered in 1995.

Stars are thought to form when gravity causes a rotating cloud of gas to contract. Before the actual star is formed, the gas collapses into a rotating disk of gas and dust particles ranging in size from tiny grains to household-sized dust to rocks and boulders. Astronomers had long predicted that some of this material may coagulate into planets as it rotates around the core, but Beta Pictoris, first detected by the Infrared Astronomy Satellite in 1983, was the first such “circumstellar” star to be imaged.

Beta Pictoris is about 63 light years from Earth in the southern constellation known as Pictor, or Painter’s Easel. It barely clears the horizon on the southern edges of the Northern Hemisphere, where it is seen most easily from Hawaii.

Like other planet-forming stars, Beta Pictoris, which is between 10 million and 20 million years old, is extremely young by stellar standards, with mature stars living billions of years. Also like some other young stars, it has an attribute that has long proved puzzling to astronomers: One side, or “wing,” of the star’s 200-billion-mile diameter dust disc is both brighter and longer than the other.

Some astronomers theorized that this anomaly was caused by the presence of a large planet orbiting the star. But the UF-led team came to a different conclusion after observing Beta Pictoris during six nights in December 2003 and last January using the Gemini telescope. The telescope had been specially equipped with a UF-designed and -built observational camera called the Thermal Region Camera and Spectograph, or T-ReCS, according to Telesco.

T-ReCS allows astronomers to detect faint sources of thermal or infrared radiation by isolating them from the far more powerful and more obvious radiation generated by the Earth’s atmosphere, the telescope and the star itself.

“We’re able to see sources that are at least a million times fainter than the background,” Telesco said. “It’s like trying to detect a match when you’re actually holding the match up to the sun.”

What Telesco characterized as “the most complete and the best resolution imaging at multiple wavelengths” of the star revealed that the wing’s brightness stemmed from a “knot” of emissions, or clump. Further examination showed this clump contained a higher concentration of smaller, finer dust particles than elsewhere, suggesting a violent and recent collision of asteroids or tiny planets.

“Many of us remember pounding chalk dust out of erasers at school,” said Scott Fisher, an astronomer at Gemini South and a co-author of the Nature paper. “After you sneeze a few times, you open a window and the fine dust blows away. In Beta Pictoris, the radiation from the star should blow away the fine particles from the collision quite rapidly. The fact that we still see them in our observations means that the collision probably happened in the past 100 years or so.”

An alternative explanation of the clump may be the “collisional grinding” of two planets located closely together in orbit, Telesco said. “Over time, the planets bang into each other, and when they do they actually produce debris,” he said.

The findings suggest a possible explanation for other observed lopsided discs, Telesco said. They also may help astronomers weed out planets from other possible sources of brightness.

“One of the problems for astronomers is if there are clumps in the disc associated with planetismals, it’s hard to tell the difference between those clumps and a planet,” he said. “So we’re hoping to use these results to understand how we can distinguish these structures from planets until the time comes when we have sensitivity to see the planet itself.”

Besides Telesco, the other UF authors of the paper are Stan Dermott, professor and chairman of the astronomy department; Thomas Kehoe, an assistant scientist; Steven Novotny, a recent UF graduate; Naibl Mariñas, a graduate student; James Radomski, a postdoctoral research associate; and Christopher Packham, an assistant scientist.

A team of scientists led by a University of Florida astronomer analyzed a sample of galaxies located 100 million light years away and discovered the number of violent encounters between large galaxies is one-tenth the number that earlier studies had suggested.

Although theoretical models had predicted fewer collisions were involved in the evolution of the universe, these are the first observational measurements confirming those assumptions, said UF astronomer Alister Graham, who will present the results Tuesday at the American Astronomical Society meeting in Denver. The research was funded by NASA through a grant from the Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy.

“The new result is in perfect agreement with popular models of hierarchical structure formation in our universe,” said Graham, a faculty scientist at the University of Florida and the Australian National University in Canberra. “Galactically speaking, things appear a little safer out there.”

For years, astronomers have known the collision and merger of galaxies resulted in the formation of larger galaxies. The biggest of these new-formed galaxies appear largely devoid of stars at their cores, a phenomenon believed to result from the damage caused by “supermassive” black holes from the smaller galaxies as they merge at the center of the new galaxy. These huge black holes, a billion times heavier than the sun, act like a giant gravitational slingshot, ejecting stars away from the galaxy cores. These black holes also have been known to devour stars that venture too near.

Together with Peter Erwin, of the Spanish Instituto de Astrofiscia de Canarias in the Canary Islands, and Ignacio Trujillo, of the Max Planck Institute for Astronomy in Germany, Graham used this deficit of core stars as a gauge to determine the number of collisions that created the large galaxies.

Prior measurements in similarly sized elliptical galaxies suggested they had been formed by eight to 10 major collisions not involving the formation of new stars, but Graham’s team arrived at a much different conclusion.

Using images from Hubble’s Wide Field Planetary Camera 2, the researchers were able to examine galaxies whose cores had not been depleted of stars. The technique allowed the astronomers to observe what the central stellar distributions looked like before any major collisions had occurred, enabling them to better reconstruct the loss of stars from the galaxies which had partially depleted cores.

In addition, by considering the overall galaxy structure, they were able to more accurately measure the mass and size of the galaxies’ centrally depleted regions, which typically ranged from 300 to 900 light years across. The result: The mass of the deficit of stars at the galaxies’ centers, on average, equaled rather than exceeded the mass of the black hole. “If there had been 10 mergers, we would have found a stellar deficit 10 times the mass of the central black hole,” Graham said.

“It’s important to realize that many galaxies have large central black holes but no depleted cores. It is therefore not the case that every black hole is formed by simply gobbling up its surrounding stars. Instead, we are observing the demolished cores of galaxies after the union of two massive cosmic wrecking balls,” he said.

Although small satellite galaxies have been captured by our galaxy, the Milky Way, it has not experienced a recent major merger, Graham said. If it had, the plane of its disk, visible as a faint wide ribbon in the night sky, would have been scattered and dispersed across the heavens. Such a fate is expected in about 3 billion years when the Milky Way collides with a neighboring spiral galaxy, Andromeda, he said.

Graham said he plans to expand his research by applying his method of analysis to more galaxies, and also will use Hubble’s Advanced Camera for Surveys, which will provide a wider field of view and enhanced sensitivity.

“This work nicely quantifies the amount of ‘damage’ that supermassive black holes do to galaxy cores during galaxy mergers,” said astrophysicist David Merritt, a professor at the Rochester Institute of Technology. “Previous work in this area had been hampered by a lack of knowledge of the initial (pre-merger) state. The new results are nicely consistent with the merger paradigm for galaxy formation, and with the observed masses of SMBHs (supermassive black holes) in galaxies. This work should motivate further simulations of galaxy mergers in order to pin down the precise effects of SMBHs on galaxy luminosity profiles.”

But don’t expect to find the star — which is at least 5 million times brighter than the sun — in the night sky. Dust particles between Earth and the star block out all of its visible light. Whereas the sun is located only 8.3 light minutes from Earth, the bright star is 45,000 light years away, on the other side of the galaxy. It is detectable only with instruments that measure infrared light, which has longer wavelengths that can better penetrate the dust.

In a National Science Foundation-funded study scheduled to be presented today at the American Astronomical Society national conference in Atlanta, the team says the star is at least as bright as the Pistol Star, the current record holder, so named for the pistol-shaped nebula surrounding it. Whereas the Pistol Star is between 5 million and 6 million times as bright as the sun, however, the new contender, LBV 1806-20, could be as much as 40 million times the sun’s brightness.

“We think we’ve found what may be the most massive and most luminous star ever discovered,” said Steve Eikenberry, a UF professor of astronomy and the lead author of a paper on the discovery that was recently submitted to the Astrophysical Journal.

Eikenberry will discuss his findings in a news conference to be held by the society at 12:30 p.m. today at the Courtland Room in the Hyatt Regency Atlanta, where the conference is being held.

One longstanding problem with gauging the brightness of stars at great distances is that what seems at first to be one amazingly bright star turns out on closer examination to be a cluster of nearby stars. Don Figer, an astronomer at the Baltimore-based Space Telescope Science Institute who led the team that discovered the Pistol Star in 1997, said the high-quality data collected by the UF-led team reduced but did not eliminate this possibility.

“The high-resolution data prove that the object is not simply a cluster of lower mass stars, although it is possible that it is a collection of a few stars in a tight orbit around each other,” Figer said. “More study will be needed to determine the distance and singularity of the object in order to establish whether the object is truly the most massive star known.”

Astronomers have known about LBV 1806-20 since the 1990s. At that time, it was identified as a “luminous blue variable star” - a relatively rare, massive and short-lived star. Such stars get their names from their propensity to display light and color variability in the infrared spectrum.

Luminous blue variable stars are extremely large, with LBV 1806-20 probably at least 150 times larger than the sun, Eikenberry said. The stars are also extremely young by stellar time. LBV 1806-20 is estimated at less than 2 million years old. The sun in our solar system, by contrast, is 5 billion years old. Typical stars, such as the sun, live 10 billion years.

LBVs have “short and troubled lives,” as Eikenberry put it, because “the more mass you have, the more nuclear fuel you have, the faster you burn it up. They start blowing themselves to bits.”

Eikenberry’s team made several key advances that led to the estimate of the star’s oversized mass and brightness, he said.

One, they sharpened infrared images obtained from the Palomar 200-inch telescope at the California Institute of Technology’s Palomar Observatory using a camera equipped with “speckle imaging,” a relatively new technology for improving resolution of objects at great distances.

“The shimmering that you see coming off a hot blacktop road in the summer - the upper atmosphere kind of does that with star light,” Eikenberry said. “Speckle imaging kind of freezes that motion out, and you get much better images.”

Composed of 17 astronomers and graduate students, the team also came up with an accurate estimate for the distance from the Earth to the bright star. Team members further determined its temperature and how much of the star’s infrared light gets absorbed by dust particles as the light makes its way toward Earth. The scientists relied on data collected by the Blanco 4-meter telescope at the National Optical Astronomy Observatory’s Cerro Tololo Inter-American Observatory in Chile.

Each of these variables contributed to the estimate of the star’s remarkable candlepower. “You correct for dust absorption, then you correct for temperature of the star, you correct for distance of the star - all of those things feed into luminosity,” Eikenberry said.

One of the mysteries about LBV 1806-20 is how it got so big. Current theories of star formation suggest they should be limited to about 120 solar masses, or 120 times as large as the sun, because the heat and pressure from such big stars’ cores force matter away from their surfaces. Eikenberry said one possibility is that the big star was formed in a process called shock-induced star formation, which occurs when a supernova blows up and slams the gaseous material in a molecular cloud together into a massive star.

The star’s size is not its only distinguishing characteristic. It is located in a small cluster of highly unusual or extremely rare stars, including a so-called “soft gamma ray repeater,” a freakishly magnetic neutron star that is one of only four identified in the entire galaxy of 100 billion stars. With a magnetic field hundreds of trillions of times more powerful than Earth’s magnetic field, this type of star gets its name from its periodic bursts of gamma rays. The cluster also apparently includes an infant or newly formed star.

“We’ve got this zoo of freak stars, all crammed together, really nearby, and they’re all part of the same cluster of stars,” Eikenberry said. “It’s really kind of weird.”

Also buried within the cluster is an extremely young infant star, Eikenberry said. The presence of the infant star, the luminous blue variable and the soft gamma ray repeater are vivid examples of an important emerging fact about stellar evolution: All stars in a single cluster don’t form at the same time, he said. “We’re seeing what I think is going to become a textbook example of the fact that stars aren’t all born in an instant, even in a small cluster,” he said.

Figer, the Pistol Star discoverer, said the research makes an important contribution to astronomers’ understanding of the star formation process.

“The findings are significant because such massive stars are very rare and define the upper limits of the star formation process,” he said. “The team has made a remarkable contribution to our understanding of the most extreme stars.”

The team carrying out this work also included UF’s Jessica LaVine; Keith Matthews, with the California Institute of Technology; Stephane Corbel, with the Universite de Paris; John-David Smith, with the University of Arizona; John Wilson, with the University of Virginia; Donald Barry, Michael Colonno and James Houck, all with Cornell University; and undergraduate research students Shannon Patel, Malia Jackson, and Dounan Hu of Cornell University; and Megan Garske of Northwestern Nazarene University.

Using images from the Hubble Space Telescope, astronomers at the University of Florida have concluded that two of the most common types of galaxies in the universe are in reality different versions of the same thing. In spite of their similar-sounding names, astronomers had for decades considered “dwarf elliptical” and “giant elliptical” galaxies to be unique. The findings, which appear in this month’s edition of The Astronomical Journal, fundamentally alter astronomers’ understanding of these important components of the universe, making it easier to understand how galaxies form in the first place.

“This helps to simplify the universe because we replace two distinct galaxy types with one,” said Alister Graham, a UF astronomer and lead author of the paper. “But the implications go beyond mere astronomical taxonomy. Astronomers had thought the formation mechanisms for these objects must be different, but instead there is a unifying construction process.”

Galaxies, the building blocks of the visible universe, are enormous systems of stars bound together by gravity and scattered throughout space. There are several different types, or shapes. For example, the Milky Way galaxy, in which the Earth resides, is a “spiral” galaxy, so named because its disk-like shape has an embedded spiral arm pattern. Other galaxies are known as “irregular” galaxies because they do not have distinct shapes. But together, dwarf and giant elliptical galaxies are the most common.

For the past two decades, astronomers have considered giant elliptical galaxies, which contain hundreds of billions of stars, and dwarf elliptical galaxies, which typically contain less than one billion stars, as completely separate systems. In many ways it was a natural distinction: Not only do giant elliptical galaxies contain more stars, but the stars also are more closely packed toward the centers of such galaxies. In other words, the overall distribution of stars appeared to be fundamentally different.

Graham, a postdoctoral research associate, and Rafael Guzmán, a UF associate professor of astronomy, decided to take a second look at the accepted wisdom. The pair analyzed images of dwarf elliptical galaxies taken by the Hubble Space Telescope and combined their results with previously collected data on over 200 galaxies. The resulting sample revealed that the structural properties of the galaxies varied continuously between the allegedly different dwarf and giant galaxy classes - in other words, these two types were just relatively extreme versions of the same object.

Sidney van den Bergh, former director and researcher emeritus at the Dominion Astrophysical Observatory at the National Research Council of Canada in Victoria, said Graham and Guzmán’s result puts to rest a “very puzzling” question.

“In astronomy, like in physical anthropology, there is a deep connection between the classification of species and their evolutionary connections,” van den Bergh said. “The bottom line is that the new work of Graham and Guzmán has made life a little bit simpler for those of us who want to understand how galaxies are formed and have evolved.”

Graham and three colleagues expand on his and Guzmán’s conclusions with a separate article that appears in the same issue of The Astronomical Journal.

In recent years, Graham said, a number of studies had revealed that the innermost centers of giant elliptical galaxies - the inner 1 percent - had been scoured out or emptied of stars. Astronomers suspect that massive black holes are responsible, gravitationally hurling away any stars that ventured too near and devouring the stars that came in really close. This scouring phenomenon had tended to dim the centers of giant elliptical galaxies, which ran counter to the trend that bigger galaxies tend to have brighter centers. The dimming phenomenon was also one reason astronomers had concluded dwarf and giant galaxies must be different types.

Building on recent revelations showing a strong connection between the mass of the central black holes and the properties of their host galaxies, Graham and his colleagues introduced a new mathematical model that simultaneously describes the distribution of stars in the inner and outer parts of the galaxy.

“It was only after allowing for the modification of the cores by the black holes that we were able to fully unify the dwarf and giant galaxy population,” Graham said.

Peter Erwin and Andres Asensio Ramos of the Instituto de Astrofísica de Canarias in Spain, and Ignacio Trujillo of the Max-Planck Institut für Astronomie in Germany, worked with Graham to support his conclusions. Both research projects were funded in part by NASA and the American Astronomical Society.

The disks, composed of giant clouds of gas and dust that surround infant stars, are around 1,000 light years away, about four times farther away than most disks seen previously. They also are by far the biggest yet observed - which suggests that planets, known to coalesce in such disks as they rotate, may exist at much greater distances from stars than any yet discovered. This observation could lead astronomers to expand the areas in which they search for new planets, a search that has so far been confined to stars’ immediate vicinities.

“You might be able to look much farther out than people have been looking and find planets,” said Richard Elston, a UF professor of astronomy who conducted the survey with his colleague and wife, UF astronomy Professor Elizabeth Lada.

Elston and Lada will present their findings during a news conference Monday at the American Astronomical Society meeting in Nashville, Tenn.

In a separate news conference, Lada will discuss her research showing that planets may come together and form in the disks in far less time than currently believed. Her findings suggest planets may form in the first 3 million years of a star’s life, much earlier than the 10-12 million years thought previously. Although 3 million years may seem like a long time, it is actually brief for stars, which can live tens of billions of years. “If you think of our Sun as a middle-age star and that middle-age people are about 36, it would seem planet formation occurs within 1 week of stellar birth,” Lada said.

As a cloud of molecular gas collapses under the pull of gravity to form a star, it rotates and the dust, gas and debris gradually gel in the shape of a two-dimensional disk. The material in these disks both feeds into the forming star and steadily coagulates into bigger and bigger chunks, which eventually form planets. The remnants of this process are visible in our own solar system, where all the planets line up, more or less, along the same two-dimensional plane.

Elston and Lada found seven such disks as part of a major survey for newborn celestial objects in “giant molecular clouds” in the constellations Orion and Perseus. These clouds, which contain the raw material for stars and planets, are the largest features of our galaxy, stretching hundreds of light years across. The clouds in this study are located approximately 1,000 light years away.

The astronomers worked at the National Science Foundation’s 2-meter, or 88-inch, telescope at the Kitt Peak National Observatory in Arizona, using a UF-developed near-infrared spectrometer and imager. The Florida Multi-object Imaging Grism Spectrometer, or FLAMINGOS, can image tens of thousands of stars in a cloud in the near-infrared each night - many more than could have been examined without the instrument. Such observations must be made in the near-infrared because visible light from young stars is nearly completely absorbed by dust in the molecular clouds, rendering the forming stars invisible to the human eye.

Computers can encode the infrared light in optical wavelengths, creating visible images. Most of these “snapshots” revealed only mature stars, and the resulting images appear similar to the sky on a clear night. However, the survey also revealed in several positions, in Elston’s words, “wild places” - startling clusters of infant stars in varied stages of formation. These stars appear in the image as colorful balls of light, with each of the seven disks resembling a dark swath surrounding each star.

Due to the blinding glare created by forming stars, such disks are not normally detectable from Earth. However, when the disk lies between Earth and a star, it masks some of the light from the star. When rendered as visible images, such nearly “edge on” disks resemble a pair of butterfly wings with a dark lane down the middle and are often called “silhouette disks.”

Astronomers used to think that stars formed in relative isolation. But over the past two decades, research by Lada and others has shown that stars usually form in clusters - celestial birthing grounds. Lada and her colleagues have shown that the majority of stars in such clusters are formed with circumstellar disks. So while it wasn’t unusual to find the disks, the surprise was that they ranged in size from 10 to 100 times larger than any of the handful of similar disks yet seen and imaged - with each disk stretching thousands of astronomical units in diameter.

One astronomical unit, the distance from the sun to Earth, measures 93 million miles. The diameter of our solar system is approximately 60 astronomical units. The fact that these disks extend many times farther than that suggests that planets, too, could extend well beyond the relatively close proximity observed in our solar system and elsewhere. That would be good news for astronomers, because the further planets are from stars, the easier they are to detect, Elston said.

In the other UF research to be presented Monday, Lada will discuss her statistical analysis of the mass contained in hundreds of young stars in clusters. She found that stars and disks in her analysis contained only enough mass to form planets for approximately 3 million years, considerably less than the 10 million or more years previously believed.

After spending nearly five years building it, a team of University of Florida scientists this month installed the world’s most advanced mid-infrared camera on the Gemini Telescope in Chile, one of the largest telescopes in the world.

Meanwhile, the Gemini Observatory, the international consortium that oversees two telescopes in Chile and Hawaii, has announced it will provide UF researchers $3.1 million to design and build a bigger, more-powerful version of a UF-developed infrared spectrometer that has been in use for nearly three years. The new tool will significantly increase the number of distant stars or galaxies that astronomers can investigate each night, leading to new information on the origins of galaxies, planets and other celestial bodies.

“Without these instruments, these telescopes are basically light collectors - they collect the light and bring it to focus,” said Richard Elston, a UF professor of astronomy and a leader of UF’s growing astronomical instrumentation program. “You have to build these instruments to do the scientific analysis, and that’s what we’re doing here.”

Astronomers interested in how galaxies or celestial bodies form typically can’t rely on visible light, because the objects they study are too far away, don’t emit much visible light, or are concealed by clouds of gas or particles.

As a result, astronomers often look for answers in lower frequency infrared light, which is emitted by all objects that generate heat. Using telescopes and instruments modified to receive this infrared light, astronomers can “see” many galaxies or celestial bodies that are otherwise invisible, because infrared light penetrates dust clouds and travels huge distances. By analyzing the different spectra of this light, astronomers can draw conclusions about these objects’ sizes, distances from the Earth, chemical compositions, temperatures and so on.

The new UF-built instruments are designed to enhance such infrared observations. They will be used first at Gemini South, which is on Chile’s Cerro Pachon mountain and is the twin of Gemini North on Hawaii’s Mauna Kea. These telescopes, which have mirrors that are about 27-foot in diameter, are among the largest in the world.

Charlie Telesco, a UF professor of astronomy, led the development of the instrument - called the Thermal Region Camera and Spectrograph, or T-ReCS - just installed on Gemini South. He said T-ReCS is expected to prove particularly useful for investigating celestial objects that have temperatures less than 200 degrees Fahrenheit, very cool by celestial standards. These include, for example, the giant, swirling discs of dust that surround stars as they form and are thought to coagulate into planets. “By imaging the dust in discs around distant stars, we can understand how planets form,” Telesco said.

Telesco added that T-ReCS also will help astronomers investigate more distant, much more faint stars. Many of these stars, and other distant objects, are so far away their light takes millions or even billions of years to reach Earth. As a result, astronomers can, in effect, use them as time travel machines to learn not only about their origins but also the genesis of the universe.

Elston conceived and developed the Florida Multi-object Imaging Grism Spectrometer - FLAMINGOS for short - designed for telescopes smaller than the Gemini’s, such as the 13-foot mirror telescope at the Cerro Tololo Inter-American Observatory near Gemini’s Cerro Pachon.

At the heart of the spectrometer is a thin metal plate with tiny holes precisely calibrated to line up with the distant galaxies or stars astronomers are studying. The plate blocks out all light except what comes from these targets. As a result, astronomers can observe and gather data from many galaxies, stars or other celestial objects at once, whereas without the instrument they could focus only on one object at a time. Instead of looking at 10 objects a night, FLAMINGOS enables astronomers to examine hundreds. That’s important because astronomers need a big sample size. “If you want to know what the sun looked like when it formed, you can’t go find the sun in its earliest form - you have to look at a whole bunch of objects and find the ones that you think are like the sun,” Elston said.

The spectrometer already has led to important new discoveries. Although astronomers continue to crunch the data, findings from the past year include six stars at critical stages in the process of forming planets, doubling the number that had been found previously.

The results have been so encouraging that the Gemini Observatory asked Elston and his colleague on the project, UF astronomy Professor Steve Eikenberry, to double the size of the spectrometer so it can be used effectively on the Gemini telescope. Expected to weigh 2 tons and measure 8 feet long, the new spectrometer, FLAMINGOS 2, will allow astronomers using Gemini to gather data from as many as five times the number of objects as FLAMINGOS - or 30 times more objects than possible using any other spectrometer in the world.

The impact of both the new mid-infrared camera and the new spectrometer will extend beyond discrete discoveries. The Gemini and other major telescopes are extremely expensive to operate. Elston said. By allowing astronomers to gather more data from each night of observation, the instruments open the door to more ambitious investigations, he said. “Now, you can go out and do things that would have been impossible before,” Elston said.

The absence of a signature doughnut-shaped ring of dusty material surrounding the massive black hole in the popularly studied M87 galaxy is making scientists rethink some of their theories, said James Radomski, a graduate student in UF’s astronomy department and member of the groundbreaking team.

Scientists anticipated that the dusty ring, which fundamentally affects our view of the nuclear cauldron in such active galaxies, would be easy to observe with new instruments on the largest telescopes. To their surprise, they found nothing in their latest observations.

The results of the study appear in this week’s issue of The Astrophysical Journal. Other team members include lead researcher Eric S. Perlman, a physicist at the University of Maryland-Baltimore County; UF astronomy professors Chris Packham and Robert Pina; and R. Scott Fisher, a scientist with the Gemini Observatory and a recent UF doctoral graduate.

“It’s more of a puzzle on what we didn’t find as opposed to what we actually found,” Radomski said. “Not seeing something we expected to see is making us rethink the entire accepted theory of how these active galaxies work and what’s powering their emissions.”

The doughnut-shaped ring, called a torus, is either missing or extremely faint, Radomski said. The observations show that all the emission the team observed can be explained as part of a huge jet coming out of the region surrounding the black hole at the heart of the galaxy, he said.

The torus should have been easy to detect because the midinfrared images of the galaxy’s center are the deepest and sharpest ever captured at these wavelengths, Packham said. The combination of the giant 8.1-meter Gemini North Telescope, one of the world’s largest telescopes, on Hawaii’s Mauna Kea, and UF’s midinfrared image/spectrometer permit such groundbreaking observations to be made, he said.

The M87 galaxy is something of a “prototype galaxy” for astronomers to test their theories because, despite being 50 million light years from Earth, it is one of the closest galaxies of its type, Packham said. When the Hubble telescope was launched, M87 was one of the first objects in the universe it looked at, he said.

Named by the amateur astronomer Charles Messier because it was the 87th object he catalogued in the sky, M87 is what’s known as an active galactic nucleus. This kind of galaxy has an incredibly high-energy beam of particles jetting from the center of a large black hole called a “super-massive black hole,” he said.

The area at the center contains the mass of about 3 billion stars compressed into a region about the size of our solar system, Packham said.

“Can you imagine putting out more energy in an area that is about the size of a solar system than from the billions of stars that make up the whole galaxy put together?” he said. “Only a small percentage of galaxies are like this.”

Astronomers believed the torus of dusty material surrounding the black hole was responsible for shaping the way we observe the powerful nuclear emission, Packham said. The torus absorbs high-energy radiation coming from the region around the black hole and helps create a huge jet, all fueled by gas and dust, he said.

“The torus has been such a key part in the accepted model of these active galactic nucleus galaxies,” Radomski said. “We may have to revise our understanding of this class of galaxies.”

The next step for researchers will be to study other galaxies to see if the lack of a visible torus is a general trend or peculiar to this particular galaxy, he said.

Fisher predicts that in the next five years astronomers are likely to make many more discoveries like that of the torus of M87 as a result of advances in modern technology.

“The new instruments and telescopes are revolutionizing the way we think about astronomy,” he said. “These observations of M87 were really made possible because we’re at this cusp of the next generation of instruments.”