Research Interests


My research seeks to understand the physical parameters and processes that most influence the evolution of galaxies. I examine the gas and star formation properties of nearby galaxies, focusing particularly on galaxies in groups and clusters where evolution is likely to be accelerated by environmental effects.

I am a member of the ALFALFA Team, led by Riccardo Giovanelli and Martha Haynes at Cornell University. The ALFALFA (Arecibo Legacy Fast ALFA) project uses the Arecibo Observatory 305-m telescope (shown at right) near Arecibo, Puerto Rico, to search for emission from neutral hydrogen (HI) in galaxies.

I am the leader of the NSF -funded Undergraduate ALFALFA Team, a consortium of 19 institutions participating in ALFALFA research. The program includes an Annual Undergraduate ALFALFA Workshop at Arecibo Observatory. Check out the webpage of the seventh Arecibo workshop, held January 12-17, 2014. Read more about the grant in a Union College Chronicle article and a NAIC newsletter article about our first Arecibo Workshop.


Recent Research Students and Projects















Lucas Viani '14

Lucas completed a physics major and astrophysics minor. He observed remotely for the ALFALFA program on his very first weekend at Union College, joining with other members of the Physics 100 Freshman Seminar class! He observed again in Winter 2011 (lower left photo and this ALFALFA blog ) .

Lucas completed two summer research projects, a sophomore scholar project, and a senior thesis on the star formation properties of the NGC 5846 group of galaxies. His Summer 2011 project was sponsored by an Undergraduate ALFALFA Team Summer Research Fellowship and his Summer 2012 project by the Union College Summer Research Program and the NASA NY Space Grant. Lucas has examined star formation characteristics of numerous members of the NGC 5846 group via R and Hα imaging obtained at two telescopes: the CTIO 0.9-m telescope through Union's participation in the SMARTS consortium and the Kitt Peak National Observatory (KPNO) in WIYN 0.9m telescope with MOSAIC through time granted to the project in April 2011. As part of this project, Lucas travelled with Prof. Koopmann to KPNO in April 2013. He is shown at the observatory at lower right. His work shows that the galaxies have reduced star formation rates and radial distributions compared to field galaxies.

Lucas also traveled with Halley Darling, Rachel Almodovar, and me to Arecibo Observatory in March 2012 and with Michael Warrener and me to Arecibo Observatory in November 2013 to observe for the L-Band Wide Followup project of intriguing ALFALFA detections. He is shown at the observatory at middle and bottom left.

Lucas was selected for a Research Experience for Undergraduates at UCLA in Summer 2013. He was nationally recognized for his academic achievements with a Goldwater Fellowship.

He has presented his work at the January 2013 meeting of the American Astronomical Society, the Fall 2011 Skidmore College Undergraduate Research Conference, the Union College Summer Research Seminar Series and the Department of Physics and Astronomy Summer Research Poster Sessions, and at the Fifth Undergraduate ALFALFA Team Arecibo workshop .

Lucas is beginning graduate school at Yale Unicersity in Fall 2014.










Michael Warrener '16

Michael is a physics major and astrophysics minor at Union. He first learned about ALFALFA and galaxy evolution in the Physics 100 Freshman Physics Seminar course. As part of that course, Michael observed remotely using the Arecibo telescope. He applied for and was accepted to carry out a 6-week Undergraduate ALFALFA Team summer research grant with Prof. Koopmann for Summer 2013, the summer after his freshman year. Michael reduced and analyzed R and Hα imaging of galaxies in a 1 square degree field of the NGC 5846 group, observations that were obtained at the KPNO WIYN 0.9m telescope with the MOSAIC camera. In the upper left picture, he points to one such galaxy. He was able to obtain his own observations in April 2014, when he accompanied me to KPNO. In the picture at lower right, he is shown with the WIYN 0.9 telescope.

After just two weeks of working in my lab, Michael helped to tutor students and faculty visiting for the Undergraduate ALFALFA Team Summer 2013 Summer Research Mini-Conference at Union. Students and faculty from 6 UAT institutions travelled to Union and another three joined the group for an afternoon research telecon. After the conference, Michael and Ryan Muther helped to train Hartwick and West Texas A&M faculty to reduce Halpha images.

Michael accompanied Lucas Viani and me to the Arecibo Observatory in November 2013 to help in an observing program designed to follow up ALFALFA detections in void regions. He returned to Arecibo in January 2014 to present his results at the Seventh NSF-Sponsored Undergraduate ALFALFA Team Workshop. He is shown in front of the Arecibo telescope at upper right and next to his poster at lower left. He has also presented his work at the Union College Summer 2014 Poster Session and at the Fall 2013 meeting of the Astronomical Society of New York at Union.

Michael was awarded a Hoffleit Undergraduate Research Scholarship at Yale University for the Summer of 2014.




Ryan Muther '16

Ryan is a computer science and history major. He was supported by a 6-week Undergraduate ALFALFA Team summer research grant for Summer 2013, the summer after his freshman year. As part of his project, Ryan used his python expertise to rewrite and enhance several image reduction programs and them to analyze several galaxies in the NGC 5846 group. His programs are being used by the Union team and the wider collaboration as they reduce Halpha images of galaxies in nearby groups.

After just two weeks of work at Union, Ryan helped to tutor students and faculty visiting for the Undergraduate ALFALFA Team Summer 2013 Summer Research Mini-Conference at Union. Students and faculty from 6 UAT institutions travelled to Union and another three joined the group for an afternoon research telecon. After the conference, Ryan and Michael Warrener helped to train Hartwick and West Texas A&M faculty to reduce Halpha images.

Ryan is shown at upper left at work in my lab. At lower left, he presents his work jointly with Michael Warrener at the Union College Summer 2014 Poster Session. He and Michael Warrener also presented a poster at the Fall 2013 meeting of the Astronomical Society of New York at Union College.








Halley Darling '13

Halley completed a physics major and astrophysics minor. She began working on ALFALFA the summer after her freshman year via a Summer 2010 project sponsored by the NASA New York Space Grant Summer Fellowship program at Union. Halley examined ALFALFA data in the northern part of the NGC 5846 group. She was surprised one day to find another group of galaxies within the field, the NGC 5775 group, including several faint, uncataloged, gas-rich galaxies! She requested and investigated ALFALFA data from a larger region around the NGC 5846 and NGC 5775 groups and worked to better characterize the environment in this area.

She continued investigating the membership of the NGC 5846 galaxy group in her sophomore year Scholar research project. As part of her project, she travelled with me to the Kitt Peak National Observatory in Arizona in April 2011 to observe NGC 5846 and other groups being analyzed by the Undergraduate ALFALFA Team Collaborative Groups Project. She used the 0.9m telescope and MOSAIC Camera to image the groups at Hα wavelengths in order to determine their star formation rates. She analyzed these data as part of her Summer 2012 research project and as her senior thesis.

During a Summer 2011 research project sponsored by the Union College Summer Research Program, she worked to write an IDL program to measure the velocity dispersion of group members.

Halley presented a poster about the Union Team's work at the Austin AAS meeting in January 2012. She attended the Fourth Undergraduate ALFALFA Team Workshop at Arecibo Observatory Jan 17-19, 2011, presenting a poster. She has also presented her work at the Union College Summer Research Seminar Series, and the Department of Physics and Astronomy Summer Research Poster Session, the Steinmetz Symposium Union College Steinmetz Symposium, and at the Fall 2011 meeting of the Astronomical Society of New York at Skidmore College, Saratoga Springs, NY.




Rachel Almodovar '15

Rachel is an astronomy major who had dreams as a child of working at Arecibo Observatory in her native Puerto Rico. These dreams came true when she started work at Union for the ALFALFA project! Rachel observed remotely at Arecibo during the first term of her freshman year as part of the Physics 100 Freshman Physics Seminar course. She joined Halley Darling, Lucas Viani, and me for an observing run at Arecibo during spring break 2012 (see photo at top of page). Rachel received funding from the NASA NY Space Grant to work on a Summer 2012 research project with me. She learned about the ALFALFA project, gas properties of galaxies, and worked on data reduction (flagbbing!) of ALFALFA data. She also translated several ALFALFA webpages describing galaxies and gas in galaxies into Spanish.





Wyatt Smith

Wyatt Smith, an advanced high school student, worked during Summer 2011 on a project to examine the nuclear activity of NGC 5846 galaxies. He developed a procedure using the topcat tool to access and cross-match catalogs such as the MPA-JHU DR7, the ALFALFA HI catalog, and the Arecibo General Catalog. He used this procedure to extract emission line measurements of NGC 5846 galaxies. and constructed a BPT diagram for the group. He also investigated emission properties as a function of groupcentric distance.

Wyatt presented his work at the Fall 2011 Astronomical Society of New York meeting and the Skidmore Undergraduate Research Conference. He is a co-author on a paper at the January 2012 AAS meeting in Austin, TX.

Wyatt attended the Fifth Undergraduate ALFALFA Team Workshop at Arecibo Observatory Jan 16-18, 2012, where he presented the results of his research and demonstrated topcat to other attendees.

Wyatt is currently a junior at Stanford University. He worked for SpaceX in Summer 2014 and is planning to be one of the first visitors to Mars!


Summer 2010 Team


Summer 2010 students (left to right) Ana Mikler, Halley Darling, SreyNoch Chin, and Katelyn O'Brien. Scroll down for information on their projects.








Katelyn O'Brien '11

Katie began her work on ALFALFA in her sophomore year with a scholar resesarch project. investigating the membership of the NGC 5846 galaxy group.

She attended the Second Undergraduate ALFALFA Team Workshop at Arecibo Observatory Jan 12-14, 2009. There she participated in observing (middle left, with P.J. Stevens of Georgia Southern University) and checked out ALFA (upper right), the detector used in the ALFALFA survey.

In January 2010, Katie presented a poster about the Union team's work on the NGC 5846 group at the AAS meeting in Washington, D.C. (lower left). Katie's poster was part of the ALFALFA poster session, in which all the first authors were women!

Katie continued work on the NGC 5846 group during the summer of 2010, supported by a Converging Technologies Summer Research Fellowship. She switched wavelengths to investigate star formation properties of 12 member galaxies via R and Halpha imaging. The observations were made at the CTIO 0.9-m telescope through Union's participation in the SMARTS consortium. She analyzed these images as her senior research project, presenting her results as a poster at the Seattle AAS meeting in January 2012.

Katie travelled to Arecibo Observatory Aug 17-23, 2010, to participate in an ALFALFA Observing run. At lower right, she and Ana Mikler '12 pause during a tour under the dish.

Katie obtained a degree in Education is now a physics teacher!






Srey Noch Chin '12

Noch worked for two summers on research within the Undergraduate ALFALFA Team Groups Project. In Summer 2009, she was sponsored by the NSF-funded Undergraduate ALFALFA Team Summer Research Program and in Summer 2010 by the Union College Summer Research Program. During Summer 2009 she analyzed the first set of data covering the center of the NGC 5846 galaxy group. In Summer 2010 she worked with the Union team to complete measurement of HI sources in a 5x8 degree region around the group. She also compared SDSS photometry to I-band photometry from the SFI++ survey (Springob et al. 2007) to test accuracy of SDSS photometry for nearby galaxies.

Noch has presented her results at the Undergraduate ALFALFA Team Summer 2009 Union College Mini-Conference, at the Fall 2009 Astronomical Society of New York meeting, at the 2009 Steinmetz Symposium at Union, and at the Third Undergraduate ALFALFA Team Workshop at Arecibo Observatory Jan 11-13, 2010.






Ana Mikler '12

Ana travelled to Washington, D.C., in Spring Term 2010 to take part in the Washington Term Away Policy Internship program. Her internship was with ALFALFA Team collaborator Jessica Rosenberg at George Mason University. Ana worked full-time 4 days a week with the George Mason Team on several analysis procedures, including an HI contouring program, a star removal program for analysis of SDSS images, and an HI mass upper limit program.

She returned to Union during Summer 2010 for a research experience funded by NSF through the Undergraduate ALFALFA Team Summer Research Program.

Ana presented her work at the Second Columbian Congress on Astronomy and Astrophysics in Bogata, Colombia, in August. She led an HI contouring activity at the Summer 2010 Undergraduate ALFALFA Team Mini-Conferences at Union College.

Ana travelled to Arecibo Observatory Aug 17-23, 2010, to participate in an ALFALFA observing run. At lower left she and Katie O'Brien pose in front of their favorite telescope.

In recognition of her research at Union, Ana received the President's Commission on the Status of Women Senior Scholarly Activity Award, given to a senior who displays outstanding activity in her field.

Ana completed her Masters in Astronomy at Astromundus in Austria and Padova, Italy, and is now pursuing a PhD at the University of Bonn in Germany.











Schuyler Smith

Schuyler, an advanced high school student, worked during Summer 2009 to convert and improve useful ALFALFA Fortran utilities into IDL and on improve existing tools to search the AGC galaxy catalog.

His work resulted in implemenations of the much-beloved programs skyd and a2010fv in IDL, which were included in the latest release of the ALFALFA LoveData code.

Schuyler attended the Third Undergraduate ALFALFA Team Workshop at Arecibo Observatory Jan 11-13, 2010. He liked observing so much that he attended all three observing sessions during the workshop! There he is, at lower left, in the Arecibo control room, observing with other members of the team. He and Noch are pictured in front of the Arecibo telescope at right.

Schuyler was chosen a U.S. Presidential Scholar in 2011 and travelled to Washington, D.C., as part of his award. Congratulations, Schuyler, on this impressive achievement! Schuyler is currently a senior at Stanford University.


John Robens '09

John received a NASA NY Space Grant Fellowship to work with me during Summer 2008. As part of his project Searching for Optical Counterparts of Galaxies and Tidal Streams Detected by the ALFALFA Survey, he analyzed optical followup images of HI sources detected by ALFALFA. The images were obtained at the 0.9m telescope at CTIO in Chile via SMARTS (Small and Moderate Aperture Telescope System). Here John presents the results of his research at the Union College Summer Seminar Series. John also presented his work at the Undergraduate ALFALFA Team Summer 2008 Mini-Conference on July 16, 2008, at Union College.

Nathan Calabro '08

Nate completed his senior thesis in Physics and Astronomy, working on a project to design an ALFALFA outreach activity, in collaboration with Jose Alonso and Brian Kent. The activity will soon be available on the ALFALFA website.

Nate travelled to Arecibo in January 2008 to present at the First Undergraduate ALFALFA Team Workshop, as shown at left top. Nate also toured the telescope and participated in an observing run. At left bottom, Nate and I pose at the Arecibo Angel Ramos Visitor Center overlook with the telescope platform in the background.

Nate plans to pursue teaching as a career. He spent Summer 2008 as an astronomy intern at the St. Paul's School in New Hampshire.






Bilal Mahmood '08


Bilal began research with me during his freshman year, analyzing H-alpha observations of galaxies. He went on to complete a sophomore scholar's project and two summer projects working on ALFALFA-related projects. He accompanied me to Arecibo in December 2006 for an ALFALFA observing run led by Martha Haynes at Cornell. During the run, he got to see the view from the top and bottom, as well as operate the telescope! He became an expert at Level I data processing (flagbb!), and is a co-author on the first ALFALFA catalog.

Bilal also presented his work at ALFALFA workshops, at the Union College Summer Seminar Series, and at the Steinmetz Symposium.

Bilal completed his medical degree at Dartmouth and is now a resident in Rochester, NY.


Last updated: Sept 1, 2014