Astronomers studying galaxy mergers using MaNGA data

(The following is a guest post by Lihwai Lin, an assistant research fellow at Academia Sinica, Institute of Astronomy and Astrophysics. She is curretnly chairing the MaNGA merger working group and organized the MaNGA merger mini-workshop described in the article below.)
Galaxies are not isolated. During the lifetime of galaxies, they may encounter another galaxy and merge together to become a larger one. Mergers can induce gas to flow toward the inner parts of galaxies through tidal forces, triggering starbursts or even “switching on” a galaxy’s central black hole (the result is called an “active galactic nucleus,” or AGN). As a result of rapid gas consumption during mergers, a galaxy may lose the majority of its gas and end up as a “dead” system with little on-going star formation. This kind of merger event is rare, but is suggested to be an important process that transforms star-forming galaxies into the quiescent population. One of the key sciences that MaNGA is attempting to address concerns the role of galaxy interactions and mergers in shaping the properties of galaxies. With just one year of the MaNGA survey, we have obtained Integral Field Unit (IFU) observations for ~150 paired galaxies, ranging from early encounters to post-mergers.
Examples of galaxy pairs selected from the SDSS. The magenta hexagons represent the IFU coverage of MaNGA. (Credit: SDSS)

Examples of galaxy pairs selected from the SDSS. The magenta hexagons represent the IFU coverage of MaNGA. (Credit: SDSS)

In early November of 2015, experts studying galaxy mergers gathered together in Taipei for the “SDSS-IV/MaNGA mini-workshop on galaxy mergers”. This 3-day workshop consists of 6 invited talks, 5 contributed talks, plus 2 discussion sessions devoted to theoretical and observational efforts, chaired by Jennifer Lotz (STScI) and Sara Ellison (University of Victoria) respectively.

Participants for the MaNGA mini-workshop on galaxy mergers, held at Academia Sinica, Institute of Astronomy and Astrophysics (ASIAA), Taipei, on Nov. 4-6, 2015.

Participants for the MaNGA mini-workshop on galaxy mergers, held at Academia Sinica, Institute of Astronomy and Astrophysics (ASIAA), Taipei, on Nov. 4-6, 2015.

With MaNGA’s spatially resolved observations for merging galaxies, we can study not only where and when the star formation is triggered and shut down during the process of  galaxy interactions, but also how the massive black holes in the center of galaxies can be fueled and grow through galaxy mergers. The observational results from MaNGA will also be compared in great detail with theoretical predictions from state-of-art simulations. Stay tuned for more exciting science that will come from MaNGA!

SDSS at the 29th General Assembly of the International Astronomical Union

The 29th General Assembly of the International Astronomical Union is due to start on Monday 3rd August 2015 in Honululu, Hawaii. These meetings happen every 3 years and are the biggest single conference in astronomy. This is your guide to all things SDSS related at IAU2015.

Thanks to generous support from the central project office, SDSS Education will be particularly well represented at IAU2015. SDSS Educational Consultant (Kate Meredith) and Director of EPO (Karen Masters) will be attending to run workshops on how to use SDSS data for education.

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This half day splinter session on Monday 10th August will give astronomers and educators (including, but very definitely not limited to members of the SDSS collaboration) a chance to participate in a hands on workshop exploring, a new educator focused resource designed to enable the use of real data from the Sloan Digital Sky Surveys in the classroom. Participants will have the opportunity to contribute their own experiences using data in the classroom into new guided journeys through Voyages for specific educational levels and/or suggest new content based on exploration of SDSS data. The schedule of the workshop is as follows:

Workshop Schedule (Drop-in Welcome), Monday 10th August 2015 in Room 327, Hawaii Convention Center.

  • 8.30am: Welcome
  • 8.40am: Mapping the Universe with SDSS (Karen Masters)
  • 9.15am: Introduction to SDSS Voyages (Kate Meredith)
  • 10.00am: COFFEE BREAK
  • 10.30am: Matching content to a curriculum (Kate Meredith)
  • 10.50am: Hands on exploration of
  • 12.00pm: Lunch/work time
  • 1.00pm: SDSS Plates and how to get one (Karen Masters)
  • 1.30pm: SDSS Plate resources online (Kate Meredith)
  • 2.00pm: END

The SDSS EPO group will run a similar workshop, but this time especially for High School Teachers as part of the Galileo Teacher Training Program, happening at the IfA, Honululu on 8th/9th August. One lucky Hawaii based teacher attending this training will be able to take an SDSS Plug Plate back to their school for use in lessons.

The SDSS EPO group will be active participants in Focus Meeting 19: Communicating Astronomy with the Public in the Big Data Era. As part of that, SDSS Director of EPO, Karen Masters will lead a discussion on what Researchers would like to Improve in Communication Initiatives. The outcome of this meeting is intended to be a Playbook on Communicating Astronomy with the Public in the Big Data Era.

There are also of course numerous science results from SDSS data being presented at the meeting. Thanks to the open data policy of SDSS many of these results are from scientists who have never been part of the SDSS Collaboration. Here is a summary of all the posters and talks at IA2015 which can obviously linked to SDSS data or projects.

Week 1 Posters:

FM16p.13. White dwarf+main sequence binaries identified from SDSS DR10, Lifang Li

FM19p.16. Galaxy Zoo: Science and Public Engagement Hand in Hand
Karen Masters; Chris Lintott; Julie Feldt; Bill Keel; Ramin Skibba

FM19p.17. SDSS Plate Packets – From Artifact to Teaching Tool
Kate K. Meredith; Karen Masters; Britt Lundgren; Oliver Fraser; Nick MacDonald

FM19p.18. SkyServer Voyages Website – Using Big Data to Explore Astronomy Concepts in Formal Education Settings
Kate K. Meredith; Karen Masters; Jordan Raddick; Britt Lundgren

S315p.193. High Resolution Molecular Gas and Star Formation in the Strongly Lensed z~2 Galaxy SDSS J0901+1814
Chelsea Sharon; Andrew Baker; Amitpal Tagore; Jesus Rivera; Charles Keeton; Dieter Lutz; Linda Tacconi; David Wilner; Alice Shapley

S315p.235. Detecting HII Regions in Z=0.1 Galaxies with Multi-Band SDSS Data
Chris Richardson; Anthony Crider; Benjamin Kaiser

Week 2 Posters:

DJp.2.15. Extreme Red Quasars in SDSS-BOSS
Fred Hamann; Nadia Zakamska; Isabelle Paris; Hanna Herbst; Carolin Villforth; Rachael Alexandroff; Nicholas Ross; Jenny Greene; Michael Strauss

DJp.2.19. Environmental dependence of AGN activity in the SDSS main galaxy sample
Minbae Kim; Youn-Young Choi; Sungsoo S. Kim

DJp.2.24. Exploring large-scale environment of SDSS DR7 quasars at 0.46Hyunmi Song; Changbom Park

FM14p.06. The link between galaxy mergers and single/double AGN: a statistical prospective from the SDSS
Xin Liu

P2.096. An efficient collaborative approach to quasars’ photometric redshift estimation based on SDSS and UKIDSS databases
Bo Han; Yanxia Zhang; Yongheng Zhao

S319p.01. SDSS J012247.34+121624, one of the most dramatic BALQSOs at redshift of 4.75 discovered by the Lijiang 2.4m Telescope
Weimin Yi

S320p.10. White dwarf + main sequence binaries identified from the data release of the Sloan Digital Sky Survey (SDSS)
Lifang Li
FM7p.06. Stellar mass of elliptical galaxies in the Sloan Digital Sky Survey
Chen-Hung Chen; Chung-Ming Ko

S319p.05. Variability of 188 broad absorption lines QSOs from the Sloan Digital Sky Survey
Weihao Bian

S319p.251. Redshift-Space Enhancement of Line-of-Sight Baryon Acoustic Oscillations in the Sloan Digital Sky Survey Main-Galaxy Sample
Haijun Tian; Mark C. Neyrinck; Tamas Budavari; AlEXANDER SZALAY



Wed 5th
12.00pm: FM4.1.05 Hot evolved stars in massive galaxies
Claire Le Cras

Mon 10th
Voyage to Education with the Sloan Digital Sky Survey
Organizer(s): Karen Masters (University of Portsmouth), Kate Meredith (Yerkes)
8:30 AM – 2:00 PM; Room 327, Hawaii Convention Center

Thurs 13th
11.35am: FM7.5.05 Age derivation from UV absorption indices and the effect of the UV upturn.
Claire Le Cras

Mon 10th
Voyage to Education with the Sloan Digital Sky Survey
Organizer(s): Karen Masters (University of Portsmouth), Kate Meredith (Yerkes)
8:30 AM – 2:00 PM; Room 327, Hawaii Convention Center

2.30pm: S319.10.03. Extreme Red Quasars in SDSS-BOSS
Fred Hamann; Nadia Zakamska; Isabelle Paris; Hanna Herbst; Carolin Villforth; Rachael Alexandroff; Nicholas Ross; Jenny Greene; Michael Strauss

Fri 14th
10.55am FM17.7.02. Synergies of CoRoT asteroseismology and APOGEE spectroscopy — Applications to Galactic Archaeology
Friedrich Anders; Cristina Chiappini; Thaíse S. Rodrigues; Andrea Miglio; Josefina Montalbàn; Benoit Mosser; Leo Girardi; Marica Valentini; Matthias Steinmetz

12.00pm S319.12.06. Redshift evolution of massive galaxies from SDSS-III/BOSS
Daniel Thomas


If you are attending the IAU2015 we hope you have a great time, and we’ll see you on Social Media Karen Masters will be tweeting as @sdssurveys on #iau2015.

The SDSS 2015 Collaboration Meeting

This past week was the 2015 SDSS Collaboration Meeting, held at the Instituto de Física Teórica IFT UAM-CSIC in Madrid, Spain (jointly organized by the Instituto de Física Teórica IFT UAM-CSIC and the Instituto de Astrofísica de Canarias).

Members of the SDSS Collaboration outside the IFT in Madrid earlier this week.

Members of the SDSS Collaboration outside the IFT in Madrid earlier this week.

You can read this news item (en Espanol) about the meeting: El “Sloan” continúa su exploración del Universo, or see this collection of Tweets by SDSS members during the meeting: Storify of #sdss15.

Social Media from the SDSS Collaborating Meeting in Madrid

This week many of us are at the Instituto de Física Teórica IFT UAM-CSIC in Madrid, Spain for our 2015 collaboration meeting (jointly organized by the Instituto de Física Teórica IFT UAM-CSIC and the Instituto de Astrofísica de Canarias).

The meeting hashtag is #sdss15.

Our twitter account @sdssurveys will be run by spokesperson, Jennifer Johnson this week. We’ll also be tweeting from survey accounts @mangasurvey (Karen Masters and Anne-Marie Weijmans), @APOGEEsurvey (by Jennifer Sobeck this week) and @eBOSSurvey (Britt Lundgren and Shirley Ho).

Join the conversation and find out what’s going on with the SDSSurveys right now.

SDSS-IV Demographics Report Presented at Inclusive Astronomy

SDSS_demographics_logo The first conference on Inclusive Astronomy was held June 17-19, 2015 at Vanderbilt University in Nashville, TN.  The conference brought together professional astronomers, sociologists, education researchers, and experts on social justice, with the aim of collectively defining recommendations and actions to make the astronomical community more diverse and inclusive.  We are proud to note that the local organizing committee for Inclusive Astronomy included members of the SDSS-IV leadership: Keivan Stassun and Kelly Holley-Bockelmann of Vanderbilt University.

Britt Lundgren (UW-Madison), who co-Chaired last year’s Committee on the Participation of Women in the SDSS (CPWS) with Karen Kinemuchi (Apache Point Observatory), presented a poster on the 2014 SDSS-IV Demographics Report.  This report details the results of a voluntary survey of the SDSS-IV collaboration’s ~500 active members, and an analysis of the SDSS-IV membership and leadership in terms of gender, location, career stage, and minority status.   The report was recently accepted for publication in the August 2015 edition of the Publications of the Astronomical Society of the Pacific, and the full text of the report is currently publicly available on the arXiv.


(Above: The basic demographic breakdown of the 250 SDSS-IV collaboration members who responded to the CPWS survey in 2014.)

Key findings from the 2014 SDSS-IV demographic report include:

  • 11% of survey respondents self-identified as a racial or ethnic minority at their current institution.
  • 25% of the SDSS-IV members are female.  This fraction is consistent with the American Astronomical Society membership, but higher than the reported fraction of female members in the International Astronomy Union (16%).
  • Large and approximately equal fractions of men (36%) and women (29%) self-identify as an SDSS-IV “leader,” perhaps due to active stakeholders being more likely to respond to a demographics survey.
  • When binned by academic age and career level, men and women in the SDSS-IV assume leadership roles at approximately equal rates, which increase steadily for both genders with increasing seniority.
  • At the highest level of SDSS-IV leadership, women disproportionately hold roles related to education and public outreach (E/PO; 3/4 female), as opposed to scientific or technical roles (2/16 female).

The efforts undertaken by the CPWS to address the demographics of the membership and leadership of SDSS-IV were very positively received at the Inclusive Astronomy conference. In addition, members of the leadership of LSST and DES in attendance voiced interest in producing similar reports from their collaborations, which will be among the largest in astronomy in coming years.   As a growing number of astronomers are participating in large international scientific collaborations, the CPWS is delighted to see other collaborations pursuing a similar accounting to ensure that these structures foster a healthy scientific climate that is both inclusive and diverse.


(Top: The gender breakdown of the SDSS-IV collaboration members, as a function of years since receiving their final degree.  Bottom: The fraction of men and women who self-reported to hold positions of leadership within the SDSS-IV, as a function of years since their terminal degree.)

The 2014 SDSS-IV Demographics Report will provide a baseline for tracking changes within the makeup of the collaboration throughout the lifetime of the SDSS-IV.  This year’s CPWS, co-Chaired by Sara Lucatello (INAF) and Aleks Diamond-Stanic (UW-Madison), recently produced a follow-up survey for 2015, which broadened the demographics investigation to a larger range of diversity metrics (e.g., LGBT, disability, and partnership / family status).  The 2015 survey achieved a ~40% higher participation rate compared to 2014, with 352 members of the collaboration responding.

A summary of the initial results from the 2015 survey will be presented at the SDSS-IV Collaboration Meeting in Madrid later this month, so stay tuned!

The CPWS is currently comprised of the following members:
Alfonso Aragon-Salamanca (Nottingham)
Katia Cunha (Observatorio Nacional / MCTI)
Aleks Diamond-Stanic (UW Madison) Co-Chair
Bruce Gillespie (JHU)
Alex Hagen (PSU)
Amy Jones (MPA)
Karen Kinemuchi (APO)
Sara Lucatello (INAF) Co-Chair
Britt Lundgren (UW Madison)
Adam Myers (Univ. of Wyoming)
Alexandre Roman Lopes (ULS)
Gail Zasowski (JHU)

Outgoing members of the CPWS from 2014 include:
Jay Gallagher (UW Madison)
Shirley Ho (CMU)
Christy Tremonti (UW Madison)

SDSS at #AAS225 – Tweets by SDSS-IV Spokesperson, Jennifer Johnson

This week the SDSS Collaboration has a large presence at the American Astronomical Society‘s 225th Meeting, being held in Seattle, Washington.

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All sorts of SDSS related stuff will be going on at this meeting, from dozens of talks and posters, to demos of SDSS online resources at the SDSS Booth in the Exhibit Hall and not to mention the final data release from SDSS-III. Our “Tweep of the Week” for this exciting week will be SDSS-IV Spokesperson, Jennifer Johnson.

Jennifer Johnson is an Asssociate Professor in the Astronomy Department of The Ohio State University. Her science interests are in stellar abundances, the origin of the elements, nucleocosmochronology and the formation of our own Galaxy and Local Group. She is the Science Team Chair of the APOGEE survey of SDSS-III, and the Spokesperson for SDSS-IV (as well as working on APOGEE-2).

Jennifer Johnson

Jennifer Johnson

The SDSS Spokesperson has two main roles. She is the main person in charge of making sure the SDSS collaboration is running smoothly and fairly. As part of this, the Spokesperson Chairs the SDSS Collaboration Council (which has a representative from each institutional member of SDSS). This group are the first point of approval for requests for Architect Status (ie. people who have contributed so much to SDSS development they can request to be on any publication) and External Collaborator requests (non-SDSS members working on specific projects), as well as for drafting our publication and other collaboration policies. They also organise the annual SDSS Collaboration Meetings (the next one to be held in Madrid, 20-23rd July 2015).

The SDSS Spokesperson is also responsible for representing SDSS to the press and the public. As such she is responsible for working with the SDSS Communications Director (Jordan Raddick) to draft the text of press releases and maintain the SDSS website, as well as with the SDSS Director of EPO (Karen Masters) on our collective public engagement and outreach efforts.

Added: here’s a storify of Tweets by Jennifer during her week.

Joint BOSS+eBOSS Collaboration in Cloudcroft, NM

Apache Point Observatory_Cloudcroft_20141203

SDSS collaboration members gathered around the telescope at an unfortunately beautiful sunset.

The SDSS-III BOSS and SDSS-IV eBOSS are in the middle of a 4-day meeting to discuss the continuing great science coming out of BOSS, looking at the first data from eBOSS, and planning for the bright future of SDSS-IV.  The location is Cloudcroft, New Mexico, which is only 17 miles from the Apache Point Observatory, home of The Sloan Foundation 2.5-meter Telescope, which has been the main telescope for SDSS for the past decade-and-a-half.  This proximity allows for collaboration members to visit the telescope and meet the hardworking mountain staff who keep it all running smoothly.

Cloudcroft has been a central landing point for all of the years of the SDSS survey, and in recognition of this, honorary membership was granted to a certain permanent member of the staff at The Lodge Resort at Cloudcroft:


MaNGA Pre-Survey Review and Team Meeting in Portsmouth, UK

Around 45 astronomers have been in Portsmouth, England this week attending the MaNGA Pre-Survey Review and Team Meeting.

MaNGA  (Mapping Nearby Galaxies at APO) is part of the plans for the next phase of the Sloan Digital Sky Survey (along with eBOSS and APOGEE2) due to start in July of this year.


The MaNGA Team and Review Panel in front of the Institute of Cosmology and Gravitation at the University of Portsmouth. Image Credit: Edd Edmondson

As well as the full science program, the astronomers have been enjoying the British pubs, Indian Food, and historic Naval ships to be found in Portsmouth.


The MaNGA Team enjoyed a special tour of HMS Warrior 1860 in the Portsmouth Historic Dockyard. Here shown just before sunset on Wednesday. Image Credit: Karen Masters

The MaNGA Team are happy with the outcome of the review, and it’s full speed ahead to survey operations. The discussions continue today and tomorrow with open issues and plans for early science papers.

We’ll always have Paris

Blog by David Weinberg (SDSS-III Project Scientist)

One-hundred and thirty scientists from four continents gathered in Paris for the second annual meeting of the SDSS-III collaboration, hosted by the laboratoire AstroParticule et Cosmologie (APC).

Paris 2010 continues a tradition that began in 1994, with the first SDSS collaboration meeting at Yerkes Observatory. Early collaboration meetings were filled with discussions of hardware, data pipelines, target selection, and survey strategy. Over the years, as the SDSS steadily accumulated the largest data sets in the history of astronomy, the proceedings shifted more and more towards scientific discoveries, about the large scale structure of the universe, the evolution of galaxies and quasars, the history of the Milky Way, the physics of stars, and the genealogy of asteroid families (see the highlights summaryat The sequence of SDSS-I and SDSS-II collaboration meetings culminated in 2008 with an international symposium that celebrated the scientific achievements and influence of the SDSS.

SDSS-III involves four new surveys, two new instruments, major upgrades to the original SDSS spectrographs and the fiber system that supports them, and many new participating institutions and scientists. The first SDSS-III collaboration meeting (Princeton, 2009) was in many ways a return to the early days, focused again on hardware, software, survey strategy, and organization of science teams.

One year along, Paris 2010 shows a project in transition, or, more precisely, four projects at four different transitions. Talks about nearly complete analyses of the chemistry and kinematics of the Galactic disks in SEGUE-2 and the aridity of the brown dwarf desert in MARVELS alternated with talks describing first measurements from the BOSS galaxy and Lyman-alpha forest surveys and the rapid progress of the APOGEE infrared spectrograph toward its commissioning in early 2011. After a day and a half of plenary sessions, the meeting split into another day and half of survey-specific parallel sessions, where team members dug into details of the science analyses, reviews of target selection efficiency, theoretical predictions and mock catalogs, and the nitty-gritty of signal-to-noise thresholds, sky coverage, and plate scheduling algorithms.

While the days started early and ran late, everyone also took the opportunity to enjoy the delights of Paris, guided expertly by LOC Chair Eric Aubourg. Highlights included the conference dinner cruise along the Seine and “wine lover’s lunches” at a small restaurant near the APC. It was asserted more than once that attending a wine lover’s lunch would improve one’s afternoon talk. This attractive hypothesis was not rigorously tested, though anecdotal evidence did not prove it obviously false.

Twenty years after the SDSS was conceived, it remains an exciting project at the cutting edge of observational astronomy, and it continues to demand the efforts, talents, and insights of a large collaboration. The collaboration meetings are intense, and they are fun.

Plus ca change, plus c’est la meme chose.

SDSS3 collaboration visits Pittsburgh

Thirty members of the BOSS Lyman-alpha Forest and Quasar Working Groups met for a workshop in Pittsburgh from Jun 21-24 , hosted by the McWilliams Center for Cosmology at Carnegie Mellon University.

The Working Groups comprise those survey members most interested in high redshift quasars and the intergalactic medium. The quasar spectra collected by the survey act as backlights, illuminating the intergalactic gas. This gas causes absorption features in the spectra (mostly the hydrogen Lyman-alpha “forest”) and by analyzing the spectra we can measure the large scale structure of intergalactic material. The prime aim of the survey is to see this structure on scales many times larger than any previous Lyman-alpha forest survey, and use the presence of the baryon oscillation feature to constrain dark energy.

The accumulation of this vast new dataset, will make many other science projects be possible, from measurements of faint quasar black hole clustering to the searches for faint traces of rare chemical elements in intergalactic space. The Pittsburgh meeting was partly dedicated to exploring these different possibilities.

BOSS Survey Scientist Kyle Dawson started the meeting off with a summary of what has been a successful first year of survey operations. There are nearly as many quasar spectra in the interesting redshift range to analyze than all previous surveys put together, and there are still 5 years of data to come.

Questions of survey strategy came up, and in particular how the signal to noise reached so far in spectra will translate into cosmological constraints. Here David Weinberg leads a discussion on how well the survey is doing.

Preliminary results from first year data were presented in many of the talks. Here Jordi Miralda-Escude reports on measurements of large-scale structure in the intergalactic medium made by the survey.

Members of the French Participation Group were heavily represented. Their team is examining every single of the tens of thousands of quasar target spectra by eye. Christophe Yeche and Isabelle Paris seen here with conference co-organizer Nic Ross show that they must be enjoying it.

Whether the SDSS3 logo looks better on an ipad was also an interesting issue for some people.

With 30 talks and working group sessions spread over 4 days, it was useful to be able continue serious discussion at a Pittsburgh landmark, the Church Brew Works: