How Stars are Born  

Elizabeth Lada's discovery   
paves way for new research on star and planet formation.  

Closing the Gap  

An article by    
UF astronomer Bo Gustafson  

The Future of the Universe   

Richard Elston's new design will allow astronomers to work 100 times faster.   

Note from the Chair  

Stan Dermott,   
Astronomy   

Astronomy Office Staff 

Oral History:
Preserving the Past   

Interview with a UF Olympian   

Dean's Musings   

And to Round Out the Year   

Around the College    

Department News   

Keene Faculty Center  
Dedicated  

Geology Celebrates 50 Years at UF  

Homecoming 1998  

New Faculty   

Profiles of Five New   
CLAS Faculty Members   

New Books from CLAS   

Grants    

Grant Awards for   
October 1998 from the Division of Sponsored Research   

CLAS notes is published monthly by the College of Liberal Arts and Sciences to inform faculty and staff of current research and events.  
  

Cn:  Last March, you and your team (Scott Fisher, Robert Piña and [from Harvard] Ray Jayawardhana) discovered what appears to be the birth of a solar system like ours, using a sophisticated infrared camera (OSCIR) you designed, built and mounted on the largest telescope at the Cerro Tololo Observatory in Chile.  The reaction in the popular press has been amazing.  All the major newspapers and radios have carried the story, and your discovery made the cover of Newsweek.  How has all the coverage affected your work?  

CT:  I think that the press and PR that we got about our discovery has actually helped us quite a bit because it's really let people know that we're doing interesting work.  It's a little hard to get that information out to the broader public and the people who really support your research when the primary way that you advertise, as it were, is through scientific journals.  
      The main thing was that a lot of people were exposed to our department.  Our department has been remade in the last few years [Telesco came in 1995], and even though the "old department" had a lot of really top-notch scientists in it, this new department is taking advantage of all kinds of recent technology, and we have new young faculty members...so this was kind of our coming out party.  This publicity helped us advertise ourselves at a very critical time.  We're hiring new faculty now, too.  We've just made a job offer that was accepted by a scientist from Cal Tech, and we're going to make two additional offers.  Those interested in applying could see that we are on the move and that we are going to be part of some major discoveries.  
      Because of the discovery and publicity, we think we're on the verge of getting involved in a big way in a really big class of telescopes.  Once we cross that line...once our university is part of a big telescope project like that--we're talking major telescopes, the biggest in the world at 8-10 meters--we'll very quickly, coupled with the new faculty that we're bringing in, be in the top class of astronomy departments, which is a pretty amazing accomplishment.  

Cn:  Describe the planet formation process.  

CT:  What we were looking at indeed seems to be the whole birth process....the creation process.  Swirling dust clouds in space contain enormous filaments of material, and for some reason that we don't fully understand, the denser parts of the filaments start to collapse in on themselves.  Little knots eventually form, and then the knots may fragment and form a lot of smaller knots which can actually begin to collapse.  They are already rotating a bit, just a random rotation, and as they collapse more they start to rotate faster, you know, like a spinning ice-skater who pulls in her arms.  Eventually, they start to flatten out to form a little disk...sort of--as the Newsweek  science editor said--like when you take a ball of dough and toss it, it stretches out into a pizza.  

A computer-enhanced version (at right) of an image Telesco's group made using OSCIR on the Keck II in Hawaii.  The central circle is the star (HR 4796A); the circles above and below are a cross-section of the kind of circumstellar disk (imagine looking at half of a doughnut edge-on) in which astronomers think planets are born.  
   
 

      Initially you get this bright, central core that will become the star [the star they worked with in Chile is called HR 4796A], and over time the dust and gas in the disk slowly coagulate and form bigger and bigger chunks of material that eventually form planetesimals [a few kilometers and bigger], and over time those coagulate and form planets, and all the dust and gas in the disk either dissipates or is captured into one of the forming planets.  We think planets usually form in the interior of the disk [which begins to look like a ring with a central cleared zone...they saw this clearing in the disk around HR 4796A].