SDSS-IV in South Korea

Last week the SDSS-IV collaboration has been having its annual all survey collaboration meeting in Seoul, South Korea. Hosted by SDSS-IV member Graziano Rossi of Sejong University, over 120 collaboration scientists from all over the world enjoyed 3 days of formal science meeting, with two days of working meetings after.

Photo of seoul plaza. The view many attendees enjoyed of the Seoul Plaza. Credit: Racheal Beaton

Conference group photo. Credit: Sejong Univ.

Photo of Korea. Many members stayed to enjoy some sightseeing before or after the meeting. Credit: Jennifer Johnson

The next collaboration meeting will be held next June in Ensenada, Baja California, Mexico hosted by scientists from UNAM Ensenada.

Text written by Karen Masters (Haverford/Portsmouth).

Documentation Fun: DocuVana 2018

We had DocuFeest in 2016, DocuCeilidh in 2017, and now it was time for DocuVana 2018. Last month, a group of enthusiastic SDSS IV-midables traveled to the University of Washington in Seattle, to prepare the SDSS webpages for its next big public data release. Data Release 15 (DR15) is planned for December 2018, and will contain new MaNGA data. It is also the first public data release for the MaNGA Stellar Library, MaStar, so lots of new documentation was needed! And it was not just the new data that created a lot of work: the APOGEE-2 team took this opportunity to go through their existing webpages, and update and improve where needed. And they already made a head start for the many new stellar spectra that they will release in 2019 in DR16.

SDSS IV-midables hard at work at DocuVana (credit: J. Sobeck)

Lots of writing was done, lost of new pages created, but in between all that typing and editing, the documentation team also took some time to explore Seattle. They enjoyed some amazing food, visited the Museum of Modern Pop Culture, and got a tour from engineer Curtis Bartosz through the UW machine shop, where all the SDSS plates are made.

The food is always good at our documentation feasts! (credit: J. Sobeck)

Inspecting plates in the University of Washington workshop (credit: J. Sobeck)

So, why did all these people take part in DocuVana? Because they care about documentation: they want to make sure that their data is not just available for downloading, but that people also can use their data: for science projects, teaching projects, or just to have a look at for fun. And to be able to do that, the data needs clear and easily accessible descriptions, examples, and tutorials.

Stay tuned for December, when you will be able to see their hard work as DR 15 goes live!


Anne-Marie Weijmans

SDSS Data Release Coordinator

University of St Andrews

SDSS-V Is Underway!

“Everything in this project makes life challenging.”

“Sure, but challenges make life interesting!”

This conversation occurred at a very special SDSS meeting in the middle of last month, and indeed no one could accuse SDSSers of ever taking it easy.  More than two years before the end of SDSS-IV, plans are well underway for its successor, SDSS-V.  Last month’s meeting was the first in-person gathering of the current major players since the Sloan Foundation awarded a $16M grant to the survey.  However, members of the team have been working hard for three years already: identifying the most exciting science goals, simulating survey strategies, and designing new hardware, among other tasks.  Dr. Juna Kollmeier, from The Carnegie Observatories, was selected as SDSS-V Director last spring, and other members of the Management Committee were chosen shortly afterwards. The core projects are now solidifying and the hardware is being prototyped. It’s an exciting (and oh so busy) time!

The science and hardware teams listen to Director Kollmeier open the meeting, in the historic library at the Carnegie Observatories in Pasadena, USA.

The team published a description of the project last fall for the astronomical community, which you can find here. In summary, SDSS-V will consist of three “Mappers,” much like how SDSS-IV now consists of eBOSS, MaNGA, and APOGEE-2.

The Milky Way Mapper will observe millions of stars in our Milky Way Galaxy and in its companion Magellanic Clouds, tabulating their motions and their compositions to study how stars form, disperse throughout space, make heavy elements, and die.  The team will also look for the signatures of planets and invisible companions (including black holes) around the stars.  The Local Volume Mapper will measure the strength of light emitted from interstellar gas in the Milky Way, the Magellanic Clouds, the Andromeda Galaxy, and other nearby galaxies.  This emission tells us about how the gas interacts with stars (especially those that are many times the mass of the Sun) as they form and die, and about how the heavy elements that these stars make are transported throughout the galaxy into later generations of stars. The Black Hole Mapper will observe many thousands of galaxy clusters and supermassive black holes in the distant Universe.  Because light from these objects left when the Universe was much younger, we can use these data to “watch” how these objects grow, change, and influence other galaxies across cosmic time.

An artist conception of the 3D Universe that SDSS-V will explore. The Earth, in the Milky Way, is at the center, and scientists peer outwards in all directions to measure the light from nearby galaxies and distant black holes. Image Credit: Robin Dienel/OCIS.


One of the classic symbols of SDSS is its “plates” — big disks of aluminum that hold the hand-plugged fiber optic cables up to our 2.5-meter telescopes.  These plates can be thought of as mini maps of the sky, with holes punched through them at the locations of the stars and galaxies we want to observe.  But all of that is changing in SDSS-V, in two major ways.  First, we’re building a couple of small telescopes to add to the ones that already exist, which the Local Volume Mapper will connect directly to six brand-new instruments for taking their measurements.  Second, SDSS-V is replacing its plates with many little robots (500 of ’em!) that are able to position the fiber optic cables anywhere in the focal plane of the telescope.  Unlike fibers plugged into the plates, the robots can move from target to target during an observation, allowing the survey to observe each star, quasar, or galaxy cluster only as long as needed and to be much more efficient.  We’ll miss our beautiful plates, but robots are pretty cool too, right?

All three Mappers will operate instruments in both hemispheres — on SDSS’s trusty 2.5-meter Sloan Telescope at Apache Point Observatory in New Mexico, USA, and on the 2.5-meter du Pont Telescope and the new small telescopes at Las Campanas Observatory in Chile.  (SDSS-IV has already established an important presence at Las Campanas.)  By using both sites, SDSS-V will have a spectroscopic view of the entire sky, because no single place on Earth can see everything.  Even though each Mapper has different science goals, SDSS scientists from all of the Mappers will continue to meet together regularly and share results, because we’re all interested in the same Universe!

SDSS-V can’t happen without the support of member institutions, though.  So if you are (or if you know) an astronomer who wants to be part of making it happen and have early access to the data and the global network of collaborators within SDSS, talk to your chair or director, and let us know how we can help!

APOGEE and Amateur Spectroscopy

Drew Chojnowski, APOGEE plate designer and lead of the emission-line stars science group, discusses SDSS and Be stars observed with the APOGEE instrument.

This weekend, APOGEEans David Whelan and Drew Chojnowski attended the Sacramento Mountains Spectroscopy Workshop. The workshop’s goal? To get amateur astronomers interested in pursuing spectroscopy. With a mix of amateurs and professionals in the room, the expertise was readily available, and the excitement was palatable.

On Friday, David Whelan lead a discussion on spectral classification of intermediate- and high-mass stars. This is a science effort that is essential to both APOGEE’s emission-line stars group and high-mass stars studies more generally. Perhaps some knowledgeable amateurs can begin to contribute?

Then on Saturday, Drew introduced the group to observing with the Sloan Telescope. Below, he is shown with one of SDSS’s APOGEE plates.

Drew and an APOGEE plate – teaching people how the SDSS is done.

These kinds of workshops break down the barrier between the amateur and the professional, and opens both groups to new possibilities. With special thanks to the organizers Ken Hudson and Joe Daglen, as well as François Cochard from Shelyak Instruments, we very much look forward to pursuing the science generated by this workshop.

The attendants of the Sacramento Mountains Spectroscopy Workshop. David and Drew are on the far right.

Amateur astronomer Joe Daglen, center, tells workshop attendants about the equipment that he uses to teach undergraduate students about imaging and spectroscopy.

SDSS in the Numbers

Scientists are inordinately fascinated by the turning over of odometers.  SDSS has recently passed three such milestones.  A list of all published refereed papers that mention “SDSS” or “Sloan Survey” in their title and abstract (link to the: custom ADS query) finds that:
-We have just passed 8000 published papers (8009 to be exact);
-We have just passed 400,000 total citations (401,609 to be exact);
-The paper that introduced SDSS to the world, York et al, has just hit 6000 citations.

A few other fun statistics:
-We have 90 papers with 500 or more citations;
-The survey’s h number is 242 (there are 242 papers with 242 or more citations);
-There are 849 papers with 100 or more citations.

This information was contributed by Prof. Michael Strauss (Princeton), Former Project Spokesperson and Deputy Project Scientist in SDSSI/II.

Job Openings: Observe for SDSS

We currently have two openings being advertised for observing staff to work within SDSS at the Apache Point Observatory, New Mexico.

To get a sense of a night of observing at Apache Point Observatory check out our Youtube video:

Please visit the links below to see the details of how to apply to be an SDSS observer.

Support Astronomer:

Telescope Operations Specialist:

A Visit to Las Campanas

Following the 2017 SDSS Collaboration Meeting, a small number of the scientists in attendance travelled to La Serena, to the North of Santiago, to participate in a trip to Las Campanas, where the APOGEE-2S instrument has been installed on the Irene du Pont Telescope. We made our own way to La Serena (by plane, or overnight bus) and met at 9.30am in the La Serena Plaza del Arms to travel to Las Campanas together.

We started our journey under thick cloud, but quickly climbed out of it for spectacular views of the Chilean Andes.

Finally Las Campanas is visible in the distance (spot the speck on the mountain).

Las Campanas is just visible as a speck on a mountain to the right of centre. Credit: Karen Masters, SDSS.

We arrived at Las Campanas around lunchtime, for a quick meal, before touring both the Irene du Pont Telescope, and the Clay 6.5 Meter Telescope (one of the two Magellan Telescopes).

Both the Magellan Telescope (right) and the du Pont Telescope (left) on Las Campanas. Credit: Karen Masters, SDSS.

We were of course especially interested to see the APOGEE infrastructure, now installed in the Irene du Pont Telescope.

Plug plate storage at the du Pont Telescope. Credit: Karen Masters, SDSS.

The APOGEE-2S Instrument. Credit: Karen Masters, SDSS

Then it was back to La Serena to head out many different ways home. Scientists from as far apart as China, Mexico, the UK, Chile and the USA had joined the trip and enjoyed visiting one of the observatories used by SDSS together.

Group shot outside the du Pont Telescope.

2017 Collaboration Meeting in Santiago, Chile

The scientists who are part of the Sloan Digital Sky Surveys gather once a year for a collaboration meeting. One of the themes of this meeting is looking for synergy and collaboration across the different surveys, and institutions which are part of SDSS.

For 2017 the meeting happened July 24-26th 2017 on the beautiful Campus San Joaquin of Pontifica Universidad de Catolica in Santiago, Chile, hosted by the Chilean Participation Group of SDSS (a collaboration of seven different Chilean Universities).

SDSS Collaboration Members attending SDSS2017. Around 120 scientists from all over the collaboration attended the meeting. The plates shown are APOGEE-2S plates brought down specially from Las Campanas.

Job Opening at The Sunspot Astronomy Visitor Center

The Sunspot Astronomy Visitor Center includes content related to the science and observations of the Sloan Digital Sky Surveys. They are seeking a new Program Co-ordinator for Education and Public Outreach. The below is reposted


New Mexico State University is seeking a program coordinator to manage the education and public outreach program at the Sunspot Astronomy Visitor’s Center.

Duties include: Oversees operations of public access to exhibits and daily tours around Sunspot Observatories. Initiates and provides local tours, plans and operates star parties: Coordinates visits from local schools and interested groups; Ensures visitor center facility is staffed during operational periods for visitors and tours as needed;  Develops a  business plan to ensure visitor center solvency; Manages gift shop including stock ordering, pricing and design and/or selection of gift shop merchandise; Manages exhibits including coordination of repairs and updates as needed; Responsible for fiscal management of Visitor’s Center;  and may require grant writing and cooperative agreements with other local tourist attractions and of state and federal agencies.  Manage staff as required.

A bachelor’s degree and/or a strong background in and knowledge of astronomy is preferred.

Job Closing Date: 08/31/2017

Targeted Start Date: 10/01/2017

Please visit to to apply

Congratulations to the APOGEE Instrument Team

Everyone at SDSS-IV wishes to congratulate the APOGEE instrument team, and especially John Wilson for being announced as the 2017 winners of the Maria and Eric Muhlmann Award of the Astronomical Society of the Pacific.

John Wilson celebrates first light for the APOGEE-S instrument. Credit: SDSS.

The award citation reads:

The Maria and Eric Muhlmann Award recognizes significant observational results made possible by innovative advances in astronomical instrumentation, software, or observational infrastructure. The 2017 recipient of the Muhlmann Award is Dr. John Wilson (University of Virginia) and the APOGEE team for the design, construction, and commissioning of the APOGEE instrument located at the Apache Point Observatory in New Mexico – the linchpin of the APOGEE surveys that have been a part of the Sloan Digital Sky Survey III (SDSS-III) and Sloan Digital Sky Survey IV (SDSS-IV).

APOGEE (Apache Point Observatory Galactic Evolution Experiment) is a groundbreaking, high-resolution, near-infrared, spectrographic survey of red giant stars in the Milky Way Galaxy. By observing near-infrared light, the custom built APOGEE instrument can efficiently see through most of the obscuring dust to study the galactic bulge, disc, and halo. Collecting spectra from 300 targets simultaneously, APOGEE is responsible for the world’s largest high-resolution, near-infrared spectroscopic survey of stars in our Galaxy. After six years of operation, APOGEE has collected data on over 250,000 stars.

As one of the nominators stated, the APOGEE instrument “produced scientifically viable data the moment it was deployed onto the sky and functioned far better than anyone expected.” The instrument was so successful that a copy has been fabricated, installed, and started operating at the 2.5-meter du Pont Telescope at Las Campanas Observatory in Northern Chile. This instrument, in a Southern Hemisphere location, together with the first instrument, provides the APOGEE Survey access to the entire Milky Way.

The award will be officially given at an Awards Gala on October 28, 2017.

Congratulations to John and the entire instrument team from all of us, and here’s to many years of APOGEE data to come from two hemispheres!

The APOGEE team in front of the instrument after it was delivered and installed in the instrument room at Las Campanas Observatory. Kneeling, from left: Garrett Ebelke, John Wilson, Jimmy Davidson. Middle: Matt Hall, Mita Tembe, Fred Hearty, Juan David Trujillo. Back: Nick MacDonald.

SDSS Fourteenth Data Release

This post was written by Anne-Marie Weijmans, the SDSS Data Release Coordinator.

It’s the last day in July, and that means that it’s time again for a Sloan Digital Sky Survey (SDSS) data release! This year, we are very happy to announce our fourteenth public data release, DR14.

Making data publicly available is an important aspect of SDSS, as it allows SDSS data to be used world-wide by anyone with an internet connection. For more than a decade, SDSS data has been used by astronomers for their science, by teachers in their classrooms[1], by students for their school projects, and by the general public to learn more about the Universe. In order to have this broad impact, we work hard to not only make our data available, but to also ensure that it is accessible. All our data is thoroughly documented, and we have various tools, tutorials and examples to assist anyone interested in using our data — from professional astronomers to high school students. Just go to the SDSS data access website to find out how you can work with the SDSS data!

All the SDSS data are stored at the servers of the Center for High Performance Computing (CHPC), at the University of Utah. This particular server holds all the SDSS data releases, including DR14. Just DR14 alone is already a whopping 156 TeraBytes (TB = 1000 Gigabyte = 1012 bytes): that is more than 33,800 DVDs worth of data! Image credit: Adam Bolton

So, what is available in DR14?

  • APOGEE-2, or the APO Galaxy Evolution Experiment-2 is very proud to announce its first public data release! APOGEE-2 studies the structure of the Milky Way by taking infra-red spectra of stars, to learn more about how the Milky Way formed and evolved over time. You can explore these spectra using our webapp and find stellar parameters and chemical properties in the APOGEE-2 data release.
  • eBOSS, short for extended Baryon Oscillation Spectroscopic Survey, is also celebrating its first public data release! eBOSS is mapping the structure of the Universe, by taking optical spectra of distant galaxies and quasars. These spectra provide distance measurements to galaxies, quasars, and intervening gas, all of which enable eBOSS to make a 3D map of the Universe, and learn more about how galaxies cluster in space. Ultimately, eBOSS aims to precisely measure the expansion rate of the Universe, and reveal more about the nature of the mysterious Dark Energy that accelerates this expansion. The eBOSS spectra are also available in our webapp.
  • MaNGA or Mapping Nearby Galaxies at Apache Point Observatory already released its first data last year, but they’re back with even more data cubes, 2,812 in total! MaNGA uses integral-field spectroscopy to map the properties of galaxies, and find out more about how different galaxies form and evolve. The MaNGA team has prepared a very handy set of tutorials to explain the data cube format, so that anyone can make use of the wealth of information hidden in these galaxy integral-field spectra.

Finally, we’re also very excited to share our new Image Policy with you! We have updated our image license to a Creative Commons Attribution license (CC-BY), which means that any image on our website may now be downloaded, linked to, or otherwise used for any purpose, provided that the image credits are given.

We hope you’ll have fun with all the spectra, catalogs, and tools included in our Fourteenth Data Release, and that they will help you with your science, outreach, teaching, school projects, and anything else!

Anne-Marie Weijmans

SDSS Data Release Coordinator

University of St Andrews

[1] If you are a teacher, we invite you to check out our latest educational guides and activities at SDSS Voyages! We are also developing a Spanish version, available here.

Spotlight on APOGEE: Engineering with Garrett Ebelke

Garrett Ebelke (center), with his wife, Stefanie, and their daughter, Madeleine

We have featured the building and delivery of APOGEE-2 several times before (like here, here, and here), so you may recognize the person we are spotlighting today. Garrett grew up in Kansas, but took an early interest in triathlons that brought him to the University of Colorado at Boulder, with all of its lovely mountains, for college. While there, he majored in astronomy. He took a class in observational astronomy that sparked his interest in working with telescopes. So after graduation, when a position as a Telescope Technologist on the 2.5-m SDSS telescope at Apache Point Observatory opened up, he jumped on it…and has been associated with SDSS ever since.

When APOGEE-1 arrived to Apache Point Observatory in 2011, Garrett was working the day shift as a fiber optics technician. His job was to plug plates for each night’s observations. As the telescope shut down for regular summer maintenance, he was asked to support the installation of APOGEE-1. This was the first time that Garrett was exposed to the engineering side of astronomy, and he says that he “was very intrigued”. Below is a picture of Garrett in the clean room with APOGEE-1, along with Principal Investigator Steve Majewski, Instrument Scientist John Wilson, and project scientist Gail Zasowski.

From left to right: Garrett Ebelke, Gail Zasowski, Steve Majewski (reflected), and John Wilson, standing together in the clean room with the APOGEE-1 instrument.

After 18 months at APO, Garrett transitioned to a job as a Telescope Operations Specialist, in which he was up at night running the observations of the SDSS telescope. He used this opportunity to begin taking engineering courses during the daylight hours, so that he could build a better background for instrumentation in astronomy. After several years (and several courses), he was approached about taking place in a unique opportunity: building APOGEE-South. In Garrett’s words: “Since I had seen both the day time plugging and night time operations, I was uniquely qualified to train the Chilean observers/pluggers. Shortly after, I began to design the Plugging and Mapping station with [Chief Engineer] French Leger. As I was handing this design off to French to finalize and fabricate, my wife Stefanie gave birth to our first daughter, Madeleine, and two weeks later, we relocated to Charlottesville, Virginia, so I could become involved in building the APOGEE-South instrument.” Talk about a busy two weeks.

From all accounts Garrett has stayed busy in Virginia ever since. It would take too long to explain everything that he has done to assist with the construction of APOGEE-South; suffice it to say that the end product, safely delivered and installed at Las Campanas Observatory, is a testament to his and many others’ hard work — see the team photo below. He has additionally assisted with upgrades at the University of Virginia’s Fan Mountain Observatory, and is in graduate school at Iowa State University pursuing a Master’s degree in Mechanical Engineering. Garrett says that his graduate coursework has been hugely beneficial to his work with APOGEE, and his impact on the team has been equally so.

The APOGEE team in front of the instrument after it was delivered and installed in the instrument room at Las Campanas Observatory. Kneeling, from left: Garrett Ebelke, John Wilson, Jimmy Davidson. Middle: Matt Hall, Mita Tembe, Fred Hearty, Juan David Trujillo. Back: Nick MacDonald.

Work for SDSS – Senior Software Developer for Apache Point Observatory

Many people contribute to the success of SDSS, not least the staff working at Apache Point Observatory, where our 2.5m Sloan Telescope is located.

The below job add for a Senior Software Developer to support engineering and observing at Apache Point Observatory is copied from a posting on the New Mexico State University website:

New Mexico State University is seeking a technical and computer-oriented person for a Senior Software Developer position to support daytime engineering and night-time astronomical observing at Apache Point Observatory (APO), in Sunspot, NM. The observatory at Sunspot NM will be location of work place. Work schedule on site is generally M-F 8-4:30.

Responsibilities include; designs, implements/installs, maintains, and administers computer, network, and phone infrastructure including hardware and software. Monitors Zenoss, overall performance to proactively identify potential issues and tune appropriately. Providse 24/7 high reliability systems with security and analysis – splunk and Bro. Performs root cause analysis on failed components and implements corrective measures. Works with others to address problems, implement new instrumentation and capabilities. Internal and external customer support and good communication skills are required. Familiar with cluster and virtual systems.

Relevant experience includes hands-on system administration, computer system and network management and development and system security. Proficiency in Unix/Linux, RedHat KVM, C, Python, VxWorks, RTEMS,FreePBX, Vyatta and VyOS,Mac OS, Modeling language – UML. Technical writing, HTML5, CSS, js, frameworks and nodej applications.

Must be able to work at 9500 ft MSL, provide critical support off hours, holidays and weekends.

Benefits: Group medical, hospital, life, dental, and disability insurance. State educational retirement, workers compensation, sick and annual leave, and unemployment compensation.

Paper/email documents will not be accepted. Required documents (CV/Resume, 3 references, unofficial copy of transcripts) must be attached to the NMSU electronic application system at

Employment is contingent on funding and eligibility for employment in U.S. and results of a background verification. Target start date is July 1, 2017.

Direct link to the posting on the NMSU website:

Where there’s a data release, there’s documentation!

Last week, more than a dozen SDSS IV-midables gathered in St Andrews, Scotland for a very important task: preparing the documentation for the Fourteenth SDSS Data Release.  This information — from high-level overviews of the surveys to column-by-column description of the files — is one of the reasons SDSS is the most highly cited dataset in the history of astronomy.  (Too strong?  No, it’s actually true: Madrid & Macchetto 2006, 2009.)

The APOGEE-2 Team love documenting – Gail Zasowksi succeeds in breaking Jen Sobeck’s concentration.

SDSS holds one of these documentation workshops for every data release: e.g., DocuFeest (DR13), DocuLuau (DR12), DocuGras (DR10), and DocuFiesta (DR9).  As the DR14 incarnation was being held in Scotland, it was dubbed the DocuCeilidh — “Ceilidh” is a Gaelic term for an evening full of traditional music, dancing, and storytelling.

The MaNGA documentation team (plus Bonnie) lay out their plans for the week.

Over four days, the DR14 DocuCeilidh team added or updated 180 webpages and rewrote more than 50 data models.  There were 12 operating Slack channels, meters of emails, and almost non-stop discussion across the tables, even as people ducked in and out of the room to sit on numerous telecons and other meetings.

More evidence of the team hard at work documenting SDSS-IV data.

Rita Tojeiro and Johan Comparat took charge of updating the information for eBOSS, which is releasing its first data in DR14.  MaNGA’s updates were overseen by Kyle Westfall, Amy Jones, David Stark, David Law, and Anne-Marie Weijmans.  In addition, José Sánchez-Gallego, Brian Cherinka, Sofia Meneses-Goytia, and Renbin Yan (joining remotely) made some advance preparations for MaNGA’s DR15 data products.  For its very first data release, APOGEE-2 was represented by Jen Sobeck and Gail Zasowski, with Jon Holtzman in close email contact (even outside of reasonable working hours…).

Jordan Raddick, Bonnie Souter, and Joel Brownstein (joining remotely) were kept busy answering technical questions, keeping a schedule, and making sure everyone had a functional platform in which to work.  SDSS-IV Spokesperson Karen Masters made great progress on the DR14 release paper, and also started adding credit lines to all images on the data release site, in advance of switching to a Creative Commons Attribution license for all SDSS images.  And Anne-Marie — in addition to the MaNGA documentation — kept a masterful hand on the organizational details and provided a steady stream of delicious treats to keep everyone fueled.

When docuCeilidhing we recommend you eat shortbread.

But even among the many, many person-hours of work put in (over 400, through the week), the Sloanies (of course) found a way to have a good time.  They explored St Andrews’ castle and cathedral ruins, sampled a wide range of Scottish whiskies, and attended a classical concert starring SDSS’s own Dr. Weijmans.  They even engaged in an exhilarating spot of ceilidh dancing, and spent a morning spying on some of the 46,200 nesting pairs of puffins on an island in the Firth of Forth.

Some of the team too a break to climb the St Rule’s Tower in St Andrews Cathedral.

A more traditional Ceilidh. Spot the SDSS-IV team members….

More evidence of dancing.

Walking for science on the Isle of May. We saw some Puffins. We went home happy.

DR14 is scheduled for July 31, and while there’s still some work to do before we deliver our latest product to the world, the DocuCeilidh accomplished quite a bit of the legwork for it to be a success.  In the meantime, plans are already in the works for the DR15 DocuTBD…stay tuned!

This post was written by Gail Zasowski.

The APOGEE-South First Light Field — APOGEE-2 Sur. Observaciones de Primera Luz

This post was written by Carlos Roman (Instituto de Astronomía, UNAM, Mexico), with help from Roger Cohen (Universidad de Concepción, Chile) and Guy Stringfellow (University of Colorado). Spanish by Carlos Roman.

La región 30 Doradus en la Nube Grande de Magallanes (NGM) fue seleccionada como objetivo para la placa de primera luz del programa APOGEE-2 Sur en el Observatorio de Las Campanas. Esto se decidió en base a algunos razonamientos importantes:

The 30 Doradus region in the Large Magellanic Cloud (otherwise known as the Tarantula Nebula) was selected as the First Light plate for the APOGEE South Survey at Las Campanas Observatory. Several reasons stand out for this choice:

Las Nubes de Magallanes, tanto la Grande como la Pequeña, son dos de los objetos más representativos de el cielo del hemisferio sur. Estas son dos de entre un grupo muy pequeño de galaxias visibles al ojo humano, sin ayuda de telescopios, y son bien conocidas por los habitantes de las regiones australes de nuestro planeta. Las Nubes de Magallanes son también los miembros más cercanos del llamado Grupo Local de Galaxias de la Vía Láctea, lo cual significa que también contienen a los ambientes extragalácticos más cercanos con los que podemos comparar lo que observamos en nuestra Galaxia. Por esta razón, han sido objeto de númerosos estudios, que incluyen mapas muy completos en muchas longitudes de onda, obtenidos con instrumentos en la Tierra y en el Espacio, y desde los observatorios más importantes, incluyendo el Telescopio VISTA del Observatorio Europeo Austral (European Southern Observatory o ESO por su sigla en inglés), o los telescopios espaciales Spitzer, Herschel y GALEX.

The Large and the Small (LMC, SMC) Magellanic Clouds are among the most representative features of the South Hemisphere sky. They are among the handful of galaxies visible to the unaided human eye and are well known to the public in all Austral regions of the planet. The Magellanic Clouds are also the closest members in the Local Group of the Milky Way, which means they are the closest extragalactic environments to which we can compare our own, and therefore they have been the subject of copious studies, that include comprehensive, multi-wavelength surveys both ground and space-based, with facilities like the ESO-Vista Telescope, the Spitzer, Herschel and GALEX space observatories.

La NGM es particularmente famosa por su actividad de formación de estrellas. A pesar de ser una galaxia de morfología irregular y de tener un tamaño relativamente pequeño, su tasa de formación estelar es extremadamente alta. Los complejos de gas molecular en la NGM contienen algunos de los cuneros estelares más brillantes que hemos podido observar, y esto es porque producen muchas estrellas masivas. De hecho, algunas de las estrellas más masivas que se conocen se formaron en la NGM, y en particular, se están formando y desarrollando en la región 30 Doradus, también conocida como la Nebulosa de la Tarántula, una hermosa región de hidrógeno ionizado (o región HII) parcialmente iluminado por el grupo de la estrella R136 en el cúmulo estelar NGC 2070. Este grupo contiene alrededor de 10 de las estrellas más masivas que se conocen, incluyendo a la estrella R136a1, con una masa que se cree supere 300 veces la del Sol, y que es tan lumuinosa como 9 millones de estrellas tipo solar. R136a1 es la estrella más masiva que conocemos.

The Large Magellanic Cloud is particularly famous for its star formation activity. Despite being an irregular, relatively small galaxy, its star forming rate is extremely high. The molecular gas complexes in the LMC host some of the brightest stellar nurseries we can observe, and this is because they produce large numbers of massive stars. In fact, some of the most massive stars known are born in the LMC and in particular, they are being born in the 30 Doradus region, also known as the Tarantula Nebula, a beautiful ionized Hydrogen (HII) region partly illuminated by the star R136 group in the stellar cluster NGC 2070. This group contains about 10 of the most massive stars known, including the source R136a1, with an estimated mass of over 300 solar masses and a luminosity almost 9 millon times higher than our Sun’s. R136a1 is currently the most massive star known to date.

La NGM fue observada como parte del programa APOGEE-2 Sur. En poco tiempo, el instrumento APOGEE proveerá de espectros infrarrojos de alta resolución de miles de estrellas en ambas Nubes de Magallanes, que proveerán de una base de datos sin precedentes que permitirá la reconstrucción de sus historias de formación estelar y de la evolución de sus poblaciones estelares, permitiendo compararlas con las de nuestra Galaxia.

The LMC will be well covered in the APOGEE-2S survey. APOGEE will provide with infrared, high resolution spectra for thousands of stars in both Magellanic Clouds, which will provide an unprecedented database that will allow the reconstruction of their star formation and chemical evolution histories, allowing us to compare them with those of the Milky Way.

La razón por la que se escogió la región 30 Doradus como el campo de primera luz para el relevamiento APOGEE-2 Sur, es debido a su importancia como objeto astronómico, pero también contó su belleza. En las figuras que incluimos abajo, mostramos algunos mapas en colores falsos de la NGM construidas con datos en varias longitudes de onda, y en donde hemos marcado la posición del campo observado con APOGEE, centrado en una posición muy cercana a 30 Doradus. En la primera imagen se muestra a la NGM en el óptico, donde podemos distinguir la población principal de estrellas en la Nube, así como varias regiones HII que se ven como zonas de nebulosidad. En la segunda imagen, vemos a la NGM como fue observada por el Levantamiento de Legado SAGE, del telescopio espacial infrarrojo Spitzer: este mapa muestra en magnífico detalle el brillo de las regiones gaseosas iluminado por estrellas recientemente formadas a lo largo y ancho de la NGM. El tercer mapa, muestra a la NGM como fue observada por el Telescopio Espacial Herschel en el infrarrojo lejano. Esta vez, el mapa traza a detalle la estructura compleja del medio interestelar en la NGM, conformado por una intrincada red de burbujas y filamentos, moldeados por los vientos de las estrellas masivas y los cúmulos estelares en las que se formaron. Sobre esta imagen, colocamos el campo de APOGEE, y señalamos con puntos pequeños todas las estrellas observadas en la placa de primera luz. Ademas, escogimos cuatro de los espectros observados, que mostramos en la parte de la derecha. Estos espectros pertenecen a cuatro estrellas muy masivas de NGM.

We chose the 30 Doradus region as the First Light plate for the APOGEE2S survey because of its importance as an astrophysical subject but also because of its beauty as illustrated in the following three image, where we have highlighted the field of view of the region we will observe with APOGEE, centered close to 30 Doradus.

DSS optical map of the LMC. We can distinguish the main stellar population of the cloud and several HII regions seen as gaseous bubbles. Image Credit: Carlos Roman, SDSS-IV and DSS.

The LMC as seen by the SAGE Legacy Survey of the galaxy made by the Spitzer Space Telescope: it shows in magnificient detail, the glow from gaseous regions illuminated by recently formed stars across the whole galaxy. Image Credit: Carlos Roman, SDSS-IV and Spitzer.

The same region but as seen with the Herschel Space Telescope in the Far-Infrared, this time tracing the complex structure of the interstellar medium of the LMC, seen as an intricated network of bubbles and filaments excavated by the winds of the massive stars and their clusters. Image Credit: Carlos Roman, SDSS-IV and Herschel.

El la cuarta figura, mostramos un acercamiento al campo de primera luz en 30 Doradus y sus alrededores, donde se señala el campo del espectrógrafo APOGEE desde el telescopio Dupont de 2.5m en su óptica principal en el Observatorio de Las Campanbas. Este campo abarca un área de poco más de 3 grados cuadrados, o 16 veces el área de la Luna llena. Dentro de esta área, se obtuvieron espectros para casi 270 objetivos científicos, que se indican en el mapa con símbolos de distintos colores.

Below we show a close-up of the 30 Doradus region and its surroundings, where we have outlined the field of view of the APOGEE spectrograph from Las Campanas Observatory 2.5m Dupont telescope. This field of view spans over 3 square degrees, 16 times the area of the full Moon. Inside this area, we have obtained spectra for 270 scientific targets, which we have also sketched in the map with different colored symbols.

Plot showing locations of proposed fibers on plate. Image Credit Carlos Roman.

La lista de objetivos propuesta incluyó:

The list of targets include:

26 Estrellas Variables Luminosas Azules (Luminous Blue Variables o LBV por su sigla en inglés) y candidatos a estrellas tipo Wolf-Rayet, incluida R136a1. Estas son fuentes muy masivas, que tienen vidas muy cortas y se formaron muy recientemente (hace unos pocos millones de años), de modo que trazan el episodio más reciente en la historia de evolución química de la NGM, y a la vez proveen información crucial sobre la cinemática y las propiedades de los cúmulos masivos de estrellas en los que se formaron. Estas estrellas muestran la fase evolucionada de estrellas muy masivas, y se sabe que muestran grandes variaciones de brillo debido al hecho de que están expulsando rápidamente sus capas externas por la acción de poderosos vientos estelares. La estrella Eta Carinae en nuestra galaxia la Vía Láctea, es un ejemplo bien conocido de este tipo de estrellas. Las LBV también tienen espectros muy característicos, con líneas que presentan lo que se conoce como perfiles tipo P-Cygni, que parecieran mostrar simultáneamente absorción y emisión. Estas características espectrales indican, precisamente, los procesos físicos relevantes a la acción de los vientos.

a) 26 Luminous Blue Variables and Wolf Rayet star candidates, including R136a1. These are very massive sources, which are very short lived and formed very recently, so they trace the current episode in chemical evolution in the LMC as well as crucial information on the kinematics and properties of the massive clusters in which they form. These stars are the evolved stages of very massive stars and they are known to have large variations in brightness due to the fact that they are expelling their external layers by powerful winds. The Milky Way star Eta Carinae is a well known example of this kind of star. LBV stars also very characteristic spectra, with lines that present what is known as a P-Cygni profile, which appears both as an emission and absorption. These features indicate, precisely, the physical processes relevant to the winds.

55 estrellas masivas (tipos espectrales OB) adicionales en el campo de 30 Doradus y en regiones cercanas de formación estelar masiva. Estos objetos fueron seleccionados a partir de una compilación, basada en fotometría infrarroja del proyecto SAGE (A. Bonanos et al., 2009 AJ, 138, 1003), y de un programa de espectroscopia óptica de las complejos de formación estelar N159/N160, localizados al Sur de 30 Doradus (C. Fariña et al., 2009, AJ, 138, 2).

b) 55 additional massive (OB) star candidates in the 30 Dor and surrounding star forming complexes. These targets were selected from the compilation of A. Bonanos, based on infrared photometry from the Spitzer SAGE Legacy Survey of the LMC (2009 AJ, 138, 1003), and from the optical spectroscopic survey of the N159/N160 star forming complexes -located South of 30 Dor- by C. Fariña (2009 AJ, 138, 2).

42 estrellas Super-gigantes, azules, amarillas y rojas. Estas estrellas son equivalentes a distintos tipos de estrellas enanas como el Sol, pero en estos casos sus clases de luminosidad las clasifican como gigantes y super-gigantes. Las estrellas azules son típicamente decenas o cientos de veces más masivas que nuestro Sol. Las estrellas amarillas son de masas más parecidas a las del Sol, mientras que las rojas son estrellas hechas con apenas una fracción de la masa del Sol.

c) 42 blue, red and yellow Supergiants. These stars are giant and supergiant (known as Class I and II) equivalents of dwarf stars like our Sun. Blue stars are typically tens to hundreds of times more massive than the Sun. Yellow stars are closer in mass to our Sun, and red stars are stars made from only a fraction of a solar mass.

80 estrellas tipo Gigantes Rojas y de Secuencia Principal, que representan la población general de la NGM, seleccionadas a partir de fotometría infrarroja. Estas fuentes proveen de una primera mirada a la cinemática, las abundancias químicas y la distribución de metalicidades en las poblaciones de estrellas de la NGM. Hay una relación importante entre estas poblaciones y las estrellas masivas que se observaron, ya que las primeras muy posiblemente se originaron en agregaciones estelares como las que ahora albergan a las estrellas masivas.

b) 80 red giant and 26 main-sequence stars from the mainstream population of the LMC, selected from near-IR photometry. These sources will provide a first look at the kinematics, the chemical abundances and the metallicity distribution function in the stellar populations of the LMC. There is an important link between these populations and the massive stars we are studying, as the first ones were most likely originated in stellar clusters like those hosting the massive stars.

40 objetos asociados con regiones del medio interestelar, principalmente regiones HII asociadas con cúmulos masivos de estrellas. Estos objetos proveen información importante acerca de las propiedades del medio interestelar (gas y polvo) en la NGM, que pueden ser trazadas por líneas características en los espectros, como las llamadas bandas interestelares difusas, pero también por líneas de absorción producidas por carbón y otros metales presentes en el polvo interestelar. La capacidad del espectrógrafo APOGEE para producir información sobre las velocidades radiales, serán esenciales para saber más sobre la estructura cinemática del medio interestelar en la NGM, y cómo las propiedades del medio se relacionan con los diversos ambientes presentes en esa galaxia.
Se incluyeron, finalmente, 32 posiciones vacías para hacer estimaciones del brillo de fondo en la región.

c) 40 targets associated to local ISM regions, mostly HII regions associated with massive star clusters. These targets will provide important information about the properties of the interstellar medium (gas and dust) in the LMC, which can be traced by specific features in the spectra, like the so-called diffuse interstellar bands, but also by absorption features that are produced by carbon and other metals in the dust. The ability of APOGEE to provide information on the radial velocities of the gas will provide crucial information about the kinematical structure of the gas in the LMC, and how the properties of the interstellar medium relate to the diversity of environments present in the galaxy.

Las observaciones de primera luz se tomaron a principios de este mes. Abajo se muestra una imagen compuesta con datos del observatorio espacial Herschel, las posiciones de las fibras usadas y algunos ejemplos de los datos que se obtuvieron.

The first light data was taken earlier this month. Below we show a composite with the Herschel data, fibres overlaid and some examples of the spectral data that was obtained.

First light data for APOGEE2-S instrument. Spectra are of massive stars in the Tarantula Nebula. Image Credit: Carlos Roman.

Here is a link to the press release about this first light for APOGEE South.