APOGEE-2S: ¡probado, embalado y enviado! Tested, Packed, and Shipped!

/ David Whelan / 1 Comment

The APOGEE-2 instrument team reached a significant milestone this week — the APOGEE-2 South spectrograph has begun its long journey to Chile! It is a clone of the spectrograph that is already operating on the Sloan Telescope, and will soon be operating on Carnegie Observatories’ du Pont telescope at Las Campanas Observatory. Reaching this milestone was no small feat; instrument components needed to be checked and re-checked, the spectrograph had to be meticulously packed, and it had to be transported across North America before being loaded on a ship.

El equipo de instrumentos de APOGEE-2 alcanzó un hito significativo esta semana, ¡el espectrógrafo APOGEE-2 Sur ha comenzado su largo viaje a Chile! Es un clon del espectrógrafo que ya está operando en el telescopio Sloan y pronto funcionará en el telescopio du Pont operado por los Observatorios Carnegie en el Observatorio de Las Campanas. Alcanzar este hito no fue una hazaña menor; las componentes del instrumento necesitaban ser revisadas una y otra vez, el espectrógrafo tenía que ser meticulosamente empaquetado y transportado a través de Norteamérica antes de ser cargado en un barco.

They say a picture is worth a thousand words, but frankly there is no other way but pictures to show how hard the APOGEE hardware team has been working to put all of the pieces together at the University of Virginia.

Dicen que una imagen vale más que mil palabras, pero francamente no hay otra forma que no sea usando imágenes para demostrar lo duro que el equipo de APOGEE ha estado trabajando para juntar todas las piezas en la Universidad de Virginia.

In the left-hand image below is technician Sophia Brunner. She is holding a small mirror, with which she is inspecting what is known as a v-groove block — a component that helps direct the fiber optic cables that pass light from the telescope to the spectrograph itself. On the right you can see a close-up of the v-groove block, with the v-grooves visible above Sophia’s hands. To the left of the v-grooves are channels filled with fiber-optic bundles. When the spectrograph is operational, light from individual stars will be passing through each fiber-optic cable, and so the v-groove block allows the light form each of those stars to be sent separately through the spectrograph and recorded. These fiber optics mean that APOGEE has the capability of simultaneously observing 300 stars!

En la imagen de la izquierda a continuación se encuentra la técnica Sophia Brunner. Ella sostiene un pequeño espejo con el que está inspeccionando lo que se conoce como un bloque de ranura en V, un componente que ayuda a dirigir los cables de fibra óptica por donde pasa la luz desde el telescopio al espectrógrafo. A la derecha se puede ver un primer plano del bloque de ranuras-V, con las ranuras visibles por encima de las manos de Sophia. A la izquierda de las ranuras-V se encuentran canales llenos de haces de fibra óptica. Cuando el espectrógrafo está en funcionamiento, la luz de las estrellas individuales pasará a través de cada cable de fibra óptica, por lo que el bloque de ranura en V permite que la luz de cada una de esas estrellas se envíe por separado a través del espectrógrafo para ser registradas. ¡Estas fibras ópticas significan que APOGEE tiene la capacidad de observar simultáneamente 300 estrellas!

Sophie Brunner is inspecting a v-groove block of the fiber assembly, shown in more detail at right. Sophie Brunner está inspeccionando un bloque de ranura en V del conjunto de fibras, que se muestra con más detalle a la derecha.

Sophie Brunner is inspecting a v-groove block of the fiber assembly, shown in more detail at right.
Sophie Brunner está inspeccionando un bloque de ranura en V del conjunto de fibras, que se muestra con más detalle a la derecha.

How do you work with fiber optic cables? The following pictures illustrate the care and attention necessary to ensure that they do not break (fiber optics are made from glass). On the left, scientist Nick MacDonald is feeding the fiber optic cables through a feed-through in the wall of the APOGEE-2S instrument. It is sort of like feeding a thread through the eye of a needle, only in this case your “thread” can break if you try to force it. On the right, machinist Charles Lam views the 50-meter long cable conduit before fiber installation. The 300 individual fibers are bundled into ten sets of 30 in so-called long-link assemblies. The instrument-side of each long-link assembly is individually fed into the instrument and terminates at a v-groove block as shown above. After all the long-link assemblies were installed they were put into a single conduit and rolled up on a big spool.

¿Cómo trabajas con cables de fibra óptica? Las siguientes imágenes ilustran el cuidado y la atención que son necesarios para asegurar que no se rompan (las fibras ópticas están hechas de vidrio). A la izquierda, el científico Nick MacDonald está alimentando los cables de fibra óptica a través de un orificio en la pared del instrumento APOGEE-2S. Es como pasar un hilo a través del ojo de una aguja, sólo que en este caso el “hilo” puede romperse si se intenta forzarlo. A la derecha, el maquinista Charles Lam inspecciona los paquetes de cables de 50 metros de largo antes de su instalación. En esta imagen, los 300 cables individuales de fibra óptica se envuelven juntos en pequeños paquetes llamados conjuntos de enlace largo; cada conjunto de enlace largo se alimenta a través de una ranura en V individualmente, como se mostró en la imagen anterior. Después de que Charles terminó de inspeccionar los paquetes, éstos se pusieron en un sólo conducto, que posteriormente se enrolló en un gran carrete.

Nick MacDonald is threading long-link assemblies through the side wall of the spectrograph (left). Charles Lam views the conduit stretched out behind the astronomy building at UVa (right). Nick MacDonald está enhebrando los ensambles de enlace largo a través de la pared lateral del espectrógrafo (izquierda). Charles Lam inspecciona todos los ensambles de enlace largo totalmente estirados, antes de ser agrupados en un conducto, justo afuera del edificio de astronomía en la Universidad de Virginia (derecha).

Nick MacDonald is threading long-link assemblies through the side wall of the spectrograph (left). Charles Lam views the conduit stretched out behind the astronomy building at UVa (right).
Nick MacDonald está enhebrando los ensambles de enlace largo a través de la pared lateral del espectrógrafo (izquierda). Charles Lam inspecciona todos los ensambles de enlace largo totalmente estirados, antes de ser agrupados en un conducto, justo afuera del edificio de astronomía en la Universidad de Virginia (derecha).

Once the fibers were in place, the instrument had to be closed up. To test that the spectrograph was working, a single fiber-optic was connected to APOGEE-2S and pointed at the Sun using a small telescope mount. The picture below of all of those happy scientists is all we need to know that the spectrograph performed to specifications.

Una vez que las fibras estuvieron en su lugar, el instrumento tenía que ser cerrado. Para probar que el espectrógrafo funcionaba, una fibra óptica fue conectada a APOGEE-2S y apuntada al Sol usando un pequeño telescopio. La imagen de abajo de estos científicos felices es todo lo que necesitamos para saber que el espectrógrafo cumplió con las especificaciones.

Professor Mike Skrutskie, along with Jimmy Davidson, Mita Tembe, Matthew Hall, and Garrett Ebelke all give the solar test a thumbs up! El Profesor Mike Skrutskie, junto con Jimmy Davidson, Mita Tembe, Matthew Hall y Garrett Ebelke dan a la prueba solar un ¡pulgar hacia arriba!

Professor Mike Skrutskie, along with Jimmy Davidson, Mita Tembe, Matthew Hall, and Garrett Ebelke all give the solar test a thumbs up!
El Profesor Mike Skrutskie, junto con Jimmy Davidson, Mita Tembe, Matthew Hall y Garrett Ebelke dan a la prueba solar un ¡pulgar hacia arriba!

Now it’s time to ship! The cryostat was closed, it was wrapped in a big tarp, loaded onto the delivery truck, and then driven to Pasadena, California.

¡Ahora es hora de enviar! El criostato fue cerrado, envuelto en una lona grande, cargado en el camión de la entrega y después conducido a Pasadena, California.

 

Screen Shot 2016-12-20 at 8.34.00 PM

The APOGEE-2S instrument sits on its load cradle(left), and is carried by forklift onto the moving truck (right). El instrumento APOGEE-2S se encuentra en su cuna de carga (izquierda) y es llevado por una carretilla elevadora al camión de carga (derecha).

The APOGEE-2S instrument and accoutrements are carefully stowed (left) before the truck is closed up and drives off (right). El instrumento APOGEE-2S y sus accesorios se guardan cuidadosamente (izquierda) antes de que el camión se cierre y comience su viaje (derecha).

The APOGEE-2S instrument and accoutrements are carefully stowed (left) before the truck is closed up and drives off (right).
El instrumento APOGEE-2S y sus accesorios se guardan cuidadosamente (izquierda) antes de que el camión se cierre y comience su viaje (derecha).

Two days later, the truck arrived at the Carnegie Observatories in Pasadena, California. The spectrograph and crates were carefully unloaded and stored, awaiting the ocean shipping container, which arrived in the middle of December.

Dos días después, el camión llegó a los Observatorios Carnegie en Pasadena, California. El espectrógrafo y las cajas fueron cuidadosamente descargadas y almacenadas, esperando el contenedor de transporte marítimo, el cual llegará a mediados de diciembre.

A forklift crew unloads APOGEE-2S at the Carnegie Observatories after a successful cross-country trek. Scientist John Wilson gratefully thanks the driving team, Ludden and Gwen, for safely transporting the spectrograph. La tripulación del montacargas descarga APOGEE-2S en los observatorios Carnegie después de un exitoso viaje. El científico John Wilson agradece al equipo de conductores, Ludden y Gwen, por transportar con seguridad el espectrógrafo.

A forklift crew unloads APOGEE-2S at the Carnegie Observatories after a successful cross-country trek. Scientist John Wilson gratefully thanks the driving team, Ludden and Gwen, for safely transporting the spectrograph.
La tripulación del montacargas descarga APOGEE-2S en los observatorios Carnegie después de un exitoso viaje. El científico John Wilson agradece al equipo de conductores, Ludden y Gwen, por transportar con seguridad el espectrógrafo.

Shipping the APOGEE-S spectrograph is a delicate business. The spectrograph has to be securely in place on the load cradle as it was in the truck, and a Shock Logger has to be placed to record any jarring movements during transportation. Below, John Wilson can be seen placing the Shock Logger on the load cradle, before the spectrograph is loaded into the shipping crate.

Transportar el espectrógrafo APOGEE-S es algo delicado. El espectrógrafo debe ser colocado cuidadosamente en su cuna de carga mientras se encuentre en el camión, así mismo se debe instalar un registrador de impactos para monitorear cualquier movimiento brusco que se produzca durante el viaje. Abajo podemos ver a John Wilson, instalando el registrador en la cuna de carga, antes de que el espectrógrafo fuera cargado.

John Wilson is mounting the Shock Logger to the APOGEE-S instrument (left). Then, John helps Greg Ortiz load APOGEE-S onto the Maersk shipping container (right). John Wilson instala un registrador de impactos al instrumento APOGEE-S (izquierda). Más tarde John ayuda a Greg Ortiz a cargar el instrumento en el contendor (derecha).

John Wilson is mounting the Shock Logger to the APOGEE-S instrument (left). Then, John helps Greg Ortiz load APOGEE-S onto the Maersk shipping container (right).
John Wilson instala un registrador de impactos al instrumento APOGEE-S (izquierda). Más tarde John ayuda a Greg Ortiz a cargar el instrumento en el contendor (derecha).

Once the instrument is loaded onto its cargo ship in Long Beach, it will take about three weeks before it reaches San Antonio, Chile. Keep your fingers crossed for a successful last leg of the journey for APOGEE-2S!

Una vez que el instrumento suba al carguero en Long Beach, tomará alrededor de tres semanas en llegar a San Antonio, Chile.¡Mantenga sus dedos cruzados para una última etapa exitosa del viaje para APOGEE-2S!

Special thanks to Andres Meza and Mariana Cano Diaz for making this dual-language blog post possible.

SDSS-IV commitment to inclusivity

/ SDSS 3 / Leave a comment

The below statement was shared with the SDSS-IV collaboration on 13th November. Following a request we now post it publicly here.

 

We write to affirm our commitment to treat every member of our collaboration with respect and dignity, regardless of their race, ethnicity, age, color, disability, faith, national origin, gender identity, gender expression, sexual orientation, social class, or political beliefs.

This week’s U.S. election results followed a long and divisive 2016 campaign. Our SDSS-IV collaboration is broad and international, and has a significant fraction of members based in the U.S. Our community comes from a range of backgrounds and experiences that may influence how they are impacted by current events.  We urge all members of the collaboration to be mindful of how we treat other members of our community during this challenging time.

We write particularly to express our solidarity with colleagues who have legitimate fears for their safety in the coming months and years. In the days following the election, some of us at U.S. institutions
have heard first-hand reports of harassment and intimidation of our colleagues and students, in some cases based on their race, of a sort that has previously been rare, and by perpetrators who expressed
political motivations.  Whatever one’s philosophy of government or beliefs about what economic, social, and foreign policies are best for the U.S., it is important that we reject such behavior; we hope that all of the U.S. national leaders will do so.

In this environment, we feel the need now to emphasize that in SDSS-IV we are committed to fostering an astronomy community that is safe, welcoming, and inclusive of all people, including those in historically marginalized groups.
SDSS-IV is currently in the process of drafting our Code of Conduct. Collaboration members are invited to comment on the current draft (link is internal website)  by emailing Jennifer Johnson (the Chair of the Code of Conduct Committee). You are also welcome to send comments to the Committee on Inclusiveness in SDSS (coins@sdss.org).

In the meantime please bring any concerns you have about collaboration climate to the collaboration management, or to our Ombudspeople, Jill Knapp and David Weinberg who can be contacted directly and confidentially via ombuds@sdss.org.

A plug plate for the South Downs Planetarium and Science Centre

/ Karen Masters / Leave a comment

Yesterday I had the pleasure of giving an SDSS Plug Plate to the South Downs Planetarium and Science Centre, in Chichester, West Sussex. This facility has been run by a team of volunteers and astronomy enthusiasts since 2002. It boasts a 100 seater planetarium, running 8-9public planetarium shows each month, as well as being available for schools bookings. I was visiting the planetarium with a group of First Year Physics students from the University of Portsmouth.

SouthDownsPlate

John Mason takes delivery of SDSS plate 3955 from SDSS-IV Spokesperson, Karen Masters.

 

The organization plan to put the SDSS plate on display, along with their other astronomy displays which include a waxwork model of famous UK amateur astronomer, Sir Patrick Moore and memorabilia from British Astronaut Tim Peake who went to school in the nearby Chichester High School. In addition they discussed plans to show the sky location the plate was designed for in future planetarium shows.

If you’d like to explore the data from this plate, which is in the direction of the constellation “Serpens”, see Plate 3955 in our Skyserver Navigate interface.

SouthDownsPlateCertificate

Certificate of Ownership for Plate 3955.

The South Downs Planetarium and Science Centre now joins museums and science centres from all over the world who display SDSS plates.

Discovery of first binary-binary calls standard model of solar system formation into question

/ Karen Masters / Leave a comment

The below is based on a press release about work by University of Florida astronomy professor Jian Ge making use of SDSS MARVELS data. We congratulate Prof. Ge and his postdoc Dr. Bo Ma on their very interesting result.

The standard picture we have for the formation of solar systems is oversimplified, according to a paper led by University of Florida astronomy professor Jian Ge and his postdoc, Bo Ma. They’ve discovered the first “binary–binary” – two massive companions around one star in a close binary system, one so-called giant planet  and one brown dwarf, or “failed star” The first, called MARVELS-7a, is 12 times the mass of Jupiter, while the second, MARVELS-7b, has 57 times the mass of Jupiter.

Artist’s conception of an extrasolar planetary system (credit: T. Riecken).

Astronomers believe that planets in our solar system formed from a collapsed disk-like gaseous cloud, with our largest planet, Jupiter, buffered from smaller planets by the asteroid belt. In the new binary system, HD 87646, the two giant companions are close to the minimum mass for burning deuterium and hydrogen, meaning that they have accumulated far more dust and gas than what a typical collapsed disk-like gaseous cloud can provide. They were likely formed through another mechanism. The stability of the system despite such massive bodies in close proximity raises new questions about how protoplanetary disks form. The findings will be published in the October issue of the Astronomical Journal.

 

HD 87646’s primary star is 12 percent more massive than our sun, yet is only 22 astronomical units away from its secondary, a star about 10 percent less massive than our sun, roughly the distance between the sun and Uranus in our solar system. An astronomical unit is the mean distance between the center of the Earth and our sun, but in cosmic terms, is a relatively short distance. Within such a short distance, two giant companions are orbiting the primary star at about 0.1 and 1.5 astronomical units away. For such large companion objects to be stable so close together defies our current popular theories on how solar systems form.

 

The planet-hunting Doppler instrument W.M. Keck Exoplanet Tracker, or KeckET, developed by a team led by Ge at the Sloan Digital Sky Survey telescope at Apache Point Observatory in New Mexico, is unusual in that it can simultaneously observe dozens of celestial bodies. Ge says this discovery would not have been possible without a multiple-object Doppler measurement capability such as KeckET to search for a large number of stars to discover a very rare system like this one. The survey of HD 87646 occurred in 2006 during the pilot survey of the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS) of the SDSS-III program, and Ge led the MARVELS survey from 2008 to 2012. It has taken eight years of follow-up data collection through collaboration with over 30 astronomers at seven other telescopes around the world and careful data analysis, much of which was done by Bo Ma, to confirm what Ge calls a “very bizarre” finding.

 

The team will continue to analyze data from the SDSS-III MARVELS survey.

Sources: Jian Ge

jge@astro.ufl.edu, 352-294-1850

Bo Ma

boma@ufl.edu, 352-294-1854

Writer: Rachel Wayne

rwayne86@ufl.edu, 352-294-7210

 

Wear the SDSS-III BOSS Data

/ Karen Masters / Leave a comment

The STEM inspired women’s fashion line “Shenova” has released it’s latest design – based on the final image of the SDSS-III BOSS catalogue. You can now wear this part of the SDSS!

This is one slice through the map of the large-scale structure of the Universe from the Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey. Each dot in this picture indicates the position of a galaxy 6 billion years into the past. The image covers about 1/20th of the sky, a slice of the Universe 6 billion light-years wide, 4.5 billion light-years high, and 500 million light-years thick. Color indicates distance from Earth, ranging from yellow on the near side of the slice to purple on the far side. Galaxies are highly clustered, revealing superclusters and voids whose presence is seeded in the first fraction of a second after the Big Bang. This image contains 48,741 galaxies, about 3% of the full survey dataset. Grey patches are small regions without survey data. Image credit: Daniel Eisenstein and the SDSS-III collaboration

As designed, Holly Renee describes, she added a colour gradient to the image on the dress to give it “distance and sparkle”. The dress is a turtleneck sheath style, but custom orders are also possible.

Screen Shot 2016-09-06 at 14.13.56

Check it out here: Shenova Online Store

Also worth a look is the Shenova Gravitational Wave Dress, which by coincidence is currently modeled on their front page by SDSS member, Prof. Kelly Holley-Bockelman from Vanderbilt University (the lead scientist for the SDSS Faculty and Student Team (FAST) initiative) as she gave a recent TEDx talk on her research work: “The Spacetime Symphony of Gravitational Waves“.

Screen Shot 2016-09-06 at 14.07.35

(Please note that SDSS receives no funds from the sale of either of these dresses, we just think they’re awesome celebrations of science and women’s fashion).

SDSS THIRTEENTH DATA RELEASE

/ Zheng Zheng / 1 Comment

This post is now in four languages: English, Chinese, Spanish and Portuguese! It is originally written by Anne-Marie Weijmans in English and translated by Zheng Zheng (to Chinese) ,  Andres Meza (to Spanish) and Ricardo Ogando (to Portuguese). 

This weekend, the Sloan Digital Sky Survey (SDSS) is celebrating its thirteenth public data release, or lucky DR13!

Data releases are an important part of the SDSS. All the data that are observed by the Sloan Telescope for the various surveys that are part of SDSS, get reduced and processed, and eventually are made publicly available. This means that everyone with access to the internet can download the data, use it for their research or teaching, or simply look at all the images and spectra that are available. You just have to go to the SDSS website, and you can start exploring the data for yourself!

So, what does DR13 have in store for you? Apart from including all the data that was released in previous data releases, there is also lots of new data:

  • DR13 is the first data release for the MaNGA survey! MaNGA stands for Mapping Nearby Galaxies at Apache Point Observatory, and it studies galaxies with integral-field spectroscopy. This allows us to study chemical elements and motions of stars and gas not just in the centre of the galaxies, but all over the galaxy outskirts too. MaNGA is releasing its spectra in datacubes for 1351 individual galaxies, making it the biggest integral-field galaxy survey available on-line so far!
  • APOGEE, or the APO Galaxy Evolution Experiment is taking infra-red spectra for hundreds of thousands of stars in the Milky Way. For this data release, they have improved the analysis of all their previously released spectra, and measured the abundances of various chemical elements of stars. This will help us understand how the Milky Way formed over time.
  • eBOSS, short for extended Baryon Oscillation Spectroscopic Survey, is mapping the structure of the Universe, by taking spectra of more than a million galaxies and quasars. Its goal is to measure the expansion rate of the Universe, and the nature of the mysterious Dark Energy that accelerates this expansion. eBOSS is releasing improved analysis of previously released spectra, as well as several catalogs with information on emission line galaxies and variable quasars.

Do you want to have a look at all of this data? Here are some places to get started:

  • The SDSS SkyServer has several tools to explore the data. You can for instance:
    • find stars and galaxies in the Navigate tool
    • look at images and spectra of stars and galaxies with the QuickLook tool
    • search for a particular sample of galaxies or stars with SQL
  • If you are interested in analyzing the data yourself, then you can find more information on how to download the data on the SDSS data access page
  • If you are a teacher and interested in activities that will help your students explore the Universe, then have a look at our SDSS education web page, with lots of resources for the class room.

Anne-Marie Weijmans
SDSS Data Release Coordinator
University of St Andrews

 

 

本周末（7月31日）斯隆数字化巡天（SDSS）迎来了它的第十三次数据释放（DR13）！

数据释放是SDSS的重要事件。所有由斯隆望远镜观测的SDSS各种巡天计划的数据，都会经过处理并对公众开放。这就意味着所有人都可以从网上找到和下载这些数据，并用来做研究、教学、或者仅仅是查看已有的图像和光谱。你只需点击进入SDSS的网站就可以查看这些数据啦！

那么，DR13里面到底都有什么呢？除了包含之前的数据释放中所有的数据以外，它还包含了很多新的数据：

  • DR13是MaNGA巡天的第一次数据释放！MaNGA是对近邻星系进行的积分场光谱巡天。有了MaNGA数据，我们还可以研究整个星系的 — 而不仅仅是星系中心的 — 元素丰度以及恒星和气体的运动。 MaNGA将释放1351个星系的IFU光谱，这也是现今在网上公开的最大的积分场星系巡天数据样本。
  • APOGEE是拍摄几十万颗银河系内恒星的红外光谱的巡天项目。在这次的数据释放中，我们改进了以前的数据处理方式，并且测量了恒星的各种元素丰度。这将会帮助我们理解银河系的形成过程。
  • eBOSS巡天用拍摄一百多万个星系和类星体的光谱的方式来描绘宇宙的结构。它的目的是测量宇宙膨胀的速度以及探寻造成宇宙加速膨胀的神秘的暗能量的本质。eBOSS不光会释放经过改进处理的以前释放过的光谱，还会释放几个包含发射线星系和变源类星体信息的星表。

你是不是已经想要看一看这些数据啦？下面列出的这些网址可以帮助你开始探索：

  • 如果你希望自己来分析数据，那么你可以在SDSS数据使用页面找到如何下载数据的相关信息
  • 如果你是一名教师并且希望利用一些活动帮助学生探索宇宙，那么你可以查看SDSS教育网站，这里面有很多相关资源可以帮助课堂教学。

 

 

Este fin de semana, Sloan Digital Sky Survey (SDSS) está celebrando su décimo tercera liberación de datos públicos o ¡afortunado DR13!

La liberación de datos es una parte importante de SDSS. Todos los datos que son observados por el Telescopio Sloan para los distintos estudios que forman parte de SDSS, son reducidos y procesados, y eventualmente puestos a disposición del público. Esto significa que cualquier persona con acceso a Internet puede bajar los datos, usarlos para su investigación, para enseñar o simplemente para ver las imágenes y los espectros que están disponibles. Sólo tienes que ir al sitio web de SDSS y ¡ya puedes comenzar a explorar los datos por ti mismo!

¿Qué tiene DR13 para ti? Además de incluir todos los datos que ya han sido hechos públicos anteriormente, también hay una gran cantidad de nuevos datos:

  • ¡DR13 es la primera liberación de datos para MaNGA! MaNGA es el acrónimo en inglés para Mapeo de Galaxias Cercanas desde el Observatorio de Apache Point, y estudia galaxias con espectroscopia de campo integral. Esto nos permite estudiar los elementos químicos y el movimiento del gas y la estrellas no solo en el centro de las galaxias, sino que también en sus partes externas. MaNGA está liberando sus espectros en cubos de datos para 1351 galaxias individuales, ¡convirtiéndolo en el estudio de campo integral más grande disponible en línea!
  • APOGEE, o experimento de Evolución Galáctica en el APO de sus siglas en inglés, está tomando espectros infrarrojos para cientos de miles de estrellas en la Vía Láctea. Para esta liberación de datos, se ha mejorado el análisis de todos los espectros publicados previamente y medido la abundancia de varios elementos químicos de las estrellas. Esto nos ayudará a entender cómo se ha formado la Vía Láctea en el tiempo.
  • eBOSS, acrónimo en inglés para Muestra Espectroscópica Extendida de la Oscilación Bariónica, está haciendo un mapa de la estructura del Universo, tomando espectros de más de un millón de galaxias y quásares. Su objetivo es medir la tasa de expansión del universo y la naturaleza de la misteriosa Energía Oscura que acelera su expansión. eBOSS está liberando análisis mejorados de sus espectros anteriores, así como también varios catálogos con información para las galaxias con líneas de emisión y quásares variables.

¿Quieres darle un vistazo a todos estos datos? Aquí hay algunos lugares para comenzar:

  • El SDSS SkyServer tiene varias herramientas para explorar los datos. Tu puedes por ejemplo:
    • Encontrar estrellas y galaxias con la herramienta Navigate.
    • Ver las imágenes y espectros de estrellas y galaxias con la herramienta QuickLook
    • Buscar un grupo particular de estrellas y galaxias con SQL.
  • Si eres un profesor y estás interesado en actividades que puedan ayudar a tus estudiantes a explorar el Universo, puedes mirar nuestra página de educación del SDSS donde hay muchos recursos para realizar en las clases.

 

 

 

Esse final de semana, o Sloan Digital Sky Survey (SDSS) celebra seu décimo terceiro lançamento de dados ao público, ou um sortudo DR13!

Os Lançamentos de Dados são uma parte importante do SDSS. Todos os dados que são observados pelo telescópio Sloan, para os vários levantamentos que são parte do SDSS, são reduzidos e processados, e em algum momento são disponibilizados para o público. Isso significa que qualquer pessoa com acesso à internet pode baixar esses dados, usar para sua pesquisa ou ensino, ou simplesmente olhar as imagens e espectros disponíveis. Basta ir à página do SDSS e começar a explorar!

Bom, mas o que é que o DR13 tem? Além dos dados de todos os lançamentos anteriores, um montão de novidades foram incluídas:

  • DR13 é o primeiro a conter dados do levantamento MaNGA! MaNGA significa Mapeamento de Galáxias Próximas no Observatório de Apache Point (em inglês, Mapping Nearby Galaxies at Apache Point Observatory), e estuda galáxias usando espectroscopia de campo integral. Isso nos permite estudar os elementos químicos e o movimento das estrelas e do gás não apenas no centro de galáxias, mas também em sua periferia. MaNGA está liberando seus espectros em cubos de dados para 1.351 galáxias, fazendo dele o maior levantamento disponível online de galáxias observadas com campo integral até hoje.
  • APOGEE, ou o Experimento de Evolução da Galáxia no APO (em inglês, APO Galaxy Evolution Experiment) está observando espectros no infravermelho para centenas de milhares de estrelas na Via-Láctea. Nesse lançamento de dados eles melhoraram a análise de todos os espectros liberados anteriormente, medindo a abundância de vários elementos químicos nas estrelas. Isso vai nos ajudar a entender como a Via-Láctea se formou e evoluiu ao longo do tempo.
  • eBOSS, abreviação de extended Baryon Oscillation Spectroscopic Survey, está mapeando a estrutura do Universo, observando espectros de mais de um milhão de galáxias e quasares. Seu objetivo é medir a taxa de expansão do Universo, e a natureza da misteriosa Energia Escura que acelera essa expansão. eBOSS está disponibilizando análises melhoradas de espectros liberados anteriormente, além de vários catálogos com informação sobre galáxias com linhas de emissão e variabilidade de quasares.

Você quer dar uma olhada em todo esse conjunto de dados? Por onde começar:

  • O SkyServer do SDSS tem várias ferramentas para explorar os dados. Você pode, por exemplo:
    • encontrar estrelas e galáxias usando o Navigate
    • olhar imagens e espectros com o QuickLook
    • procurar por uma amostra de galáxias ou estrelas em particular usando SQL
  • Se você está interessado em analisar os dados você mesmo, você pode encontrar mais informações de como baixar os dados na página SDSS data access
  • Se você for um professor e está interessado em atividades que possam ajudar seus estudantes a explorar o Universo, dê uma olhada em nossa página educativa, com vários recursos para a sala de aula.

 

 

It takes a large team of people to put together a data release: from collecting the data at the telescopes, to processing the data, analyzing the data, and documenting the data. The SDSS DR13 website, that describes all the various datasets now available in DR13, was mostly written at DocuFeest, by a dedicated group of SDSS scientists. Image credit: Jennifer Johnson.  数据释放要经过很多环节：从望远镜收集数据、处理数据、分析数据、以及准备相关文档，这是我们大团队共同努力的结晶。SDSS DR13网站描述了DR13中包含的所有数据，这个网站大部分都是由一批SDSS科学家在DocuFeest上完成的。照片由Jennifer Johnson提供。 Se debe reunir un grupo grande de personas para generar los datos públicos: desde recolectar los datos en los telescopios, luego procesar y analizar los datos, hasta finalmente documentarlos. El sitio para el DR13, que describe todos los conjuntos de datos ahora disponibles, fue escrito en su mayor parte en el DocuFeest por un grupo dedicado de científicos de SDSS.  Concluir um lançamento de dados requer um grande time de pessoas: da coleta de dados nos telescópios, ao seu processamento, análise, e documentação. A página do DR13 do SDSS, que descreve todos os distintos conjuntos de dados agora disponíveis no DR13, foi quase toda escrita por um dedicado grupo de cientistas do SDSS numa reunião batizada de DocuFeest (Feest é festa em holandês, origem de uma das organizadoras do evento de documentação). Crédito da imagem: Jennifer Johnson.

 

Caption: all the SDSS data are stored at the servers of the Center for High Performance Computing (CHPC[https://chpc.utah.edu/]), at the University of Utah. This particular server holds all the SDSS data releases, including DR13. The total data volume is about 267 TeraBytes (TB = 1000 Gigabyte = 1012 bytes): that is more than 58,000 DVDs worth of data! Image credit: Adam Bolton.

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 DR13. The total data volume is about 267 TeraBytes (TB = 1000 Gigabyte = 1012 bytes): that is more than 58,000 DVDs worth of data! Image credit: Adam Bolton.  所有的SDSS数据都存储在美国犹他大学高性能计算中心（CHPC）的服务器上。这台服务器存储着所有SDSS释放过的数据，包括DR13。整个数据容量大约是267T （1T=1000G=1012 bytes）：这比58000张DVD包含的数据都要多！照片由Adam Bolton提供。 Todos los datos de SDSS están almacenados en los servidores del Centro de Computación de Alto Rendimiento de la Universidad de Utah. Este servidor contiene todos los datos públicos, incluyendo DR13. El volumen total de datos es de alrededor de 267 TB, ¡esto es más de 58.000 DVDs!  Todos os dados estão armazenados em servidores no Center for High Performance Computing (CHPC), na University of Utah. Esses servidores em particular contem todos os lançamentos de dados do SDSS, incluindo o DR13. O volume total de dados é de cerca de 267 Terabytes (TB = 1000 Gigabyte = 1012 bytes): isso é mais que 58.000 DVDs cheios de dados! Crédito da imagem: Adam Bolton.

 

montage_1st_gal_plate

The very first 17 galaxies observed by MaNGA, one plate full! These galaxies are all included in DR13. Some galaxies have been off-set from the centre of the IFU to allow inclusion of foreground stars, to test our measurement precisions (this was only done for this first commissioning plate). Image credit: Kevin Bundy.  这17个星系来自MaNGA的首次观测，是在同一个光纤插板上的所有星系！这些星系都包含在DR13里面。有些星系偏离了IFU的中心，这是因为我们要同时拍摄一些前景恒星用来检测测量精度 (不过这种情况只发生在这第一个光纤插板上)。照片由Kevin Bundy提供。 ¡Las primeras 17 galaxias observadas por MaNGA en una sola placa! Todas estas galaxias están incluidas en el DR13. Algunas galaxias han sido desalineadas del centro del IFU para incluir estrellas en el fondo, las cuales permiten probar la precisión de las mediciones (esto fue hecho sólo para esta primera placa).  As 17 primeiríssimas galáxias observadas pelo MaNGA, são um verdadeiro gol de placa! Essas galáxias foram todas incluídas no DR13. Algumas galáxias foram deslocadas do centro do IFU para incluir estrelas, a fim de testar a precisão de nossas medidas (isso foi feito apenas para essa placa inaugural de comissionamento do instrumento). Crédito da imagem: Kevin Bundy.

SDSS Collaboration Meeting 2016: Madison, Wisconsin, USA

/ Jennifer Johnson / 1 Comment

At the end of June 2016, over 150 members of the SDSS collaboration met for workshops, talks, discussions, and fun by the lake at the University of Wisconsin, Madison. The week began with a two-day APOGEE workshop on Saturday and Sunday. On Sunday, the APOGEEans were joined in Madison by the FAST/REU bootcamp and the Plate workshop for teachers and scientists.

2016 SDSS collaboration meeting photograph. The happy attendees gathered by the beautiful lake. If you were there and not in this picture, you were probably getting coffee.

2016 SDSS collaboration meeting photograph. The happy attendees gathered by the beautiful lake. If you were there and not in this picture, you were probably getting coffee.

The FAST/REU students were getting up to speed really quickly on how to work with our data. The REU students are undergraduates who will be working on a science project over the summer, while the FAST students are graduate students in longer term teams with SDSS as we seek to help raise the participation of under-represented minorities.

On Monday-Wednesday, the meeting focused on discussions of SDSS-IV science, including many exciting results from the MaNGA survey, which is releasing its first data in Data Release 13. The APOGEE-2 survey present maps of the composition of stars across the Galaxy, characterizing the trends with position. The eBOSS survey showed the first results for large-scale structure of the Universe based on the 2014-2016 observations (very fast turn-around!). Quasars were also a big topic of conversation, as SDSS is now studying their evolution in detail. We are interested both in how they change over a few years time and mapping how they “grow” the supermassive black holes over billions of years. Results discussed that have been highlighted by SDSS in press releases/blog posts include the shutting off of star formation in galaxies by Edmond Cheng , additional examples of “changing look quasars” by Jessie Runnoe and the discovery that brown dwarfs could be quite common around certain types of stars by Nick Troup.

Poster for Daniel Eisenstein's public talk

Poster for Daniel Eisenstein’s public talk

We saw ways that other galaxies could “quench” their star formation in the presentation by Francesco Belfiore and could study the history of star formation in our Galaxy thanks to age maps by Melissa Ness. Apparently our galaxy has some similarities to other spiral galaxies! We tweeted a whole bunch about about the science results and will Storify some of our most popular tweets soon.

On Tuesday night, we had the collaboration meeting banquet, where we honored Dan Long, longtime Sloanie who worked at Apache Point Observatory for over 20 years, including as Chief Telescope Engineer for the Sloan Foundation Telescope. He is retiring next year and, as the email from Jim Gunn put it, “we will miss him more than I can say.” In addition to spoken tributes, we also showed of a movie of some of Dan’s greatest hits and well-wishes from the many other Sloanies. We will be posting that to youtube soon, so stay tuned.

The SDSS collaboration is big and includes people from many career stages, institutions, and cultures. We take the opportunity of these meetings to discuss how the collaboration is working and what we can do better. There was a thoughtful and thought-provoking discussion of how to improve the climate in SDSS and how to establish a “Code of Conduct” that will work to ensure that all are treated with respect.

This meeting also featured our first public talk by Daniel Eisenstein, talking about using the disturbances that sound waves left in the gas of the early Universe to trace the shape, past, and future of the Universe. He’s been working with SDSS data on this subject for over 10 years, so is a leading expert in this amazing result. The April 2016 edition of Sky and Telescope featured the article “Mapping the Universe’s Ancient Sound Waves” written by Daniel. The “Beyond the Pages” addition by the editors is also wonderful.

We had our most ambitious meeting ever for education and public outreach. The Plate Workshop on how to use an SDSS plate to introduce your class to the science of SDSS had a number of educators from across the US attending, looking pretty happy when they got their picture taken.

Educators from the Plate Workshop, organized by Kate Meredith (bottom right) and Karen Masters (who is probably taking the picture)

Educators from the Plate Workshop, organized by Kate Meredith (bottom right) and Karen Masters (who is probably taking the picture)

The Sunday workshop was followed on Monday and Tuesday by educators attending science talks, working with SDSS scientists on education and public outreach ideas, and doing an “EPO Hack Day” to create new activities for Voyages, SDSS’s website for how to use our data for education for K-12 students.

Thanks to the University of Wisconsin, especially the head of the Local Organizing Committee, Christy Tremonti, for hosting such a lovely meeting and we look forward to seeing everyone at the next meeting next summer.

SDSS Celebrates Leaders Inducted into the National Academy of Sciences

/ David Whelan / Leave a comment

This year, we are pleased that two scientists related to the SDSS collaboration have been recognized for their wide contributions to astronomical research.

Professor Meg Urry, of Yale University, has served on the Advisory Committee for SDSS-III and SDSS-IV. Her research focuses of supermassive black holes, and she is known, among other things, for her work that demonstrates Active Galactic Nuclei are a common phase in galaxy evolution.

Dr. Meg Urry of Yale University

Dr. Meg Urry of Yale University

Professor Timothy Heckman, of John Hopkins University, has also served on the Advisory Committee for SDSS, as well as being an Astrophysical Research Consortium Board member from 1995 to 2000. His research touches upon the ways that supermassive black holes effect their host galaxies.

Dr. Timothy Heckman, Johns Hopkins University

Dr. Timothy Heckman, Johns Hopkins University

Congratulations to both Timothy and Meg on their achievements!

Red Geysers in MaNGA: New Evidence for AGN Maintenance Mode Feedback

/ Zheng Zheng / 2 Comments

(This is a guest post by Edmond Cheung at the Kavli IPMU)

While there have been many recent studies addressing how galaxies shut off, or quench, their star formation, an equally interesting yet relatively unstudied question is how these quenched galaxies remain quenched. This is interesting because these quiescent galaxies often contain gas (from stellar mass loss or mergers) that—if left unimpeded—should cool and form stars. But since we know that quiescent galaxies have not formed a significant amount of stars since they’ve been quenched, there must be something that prevents this gas from cooling.

In the new study by Cheung et al. 2016, Nature, 533, 504, this ‘something’ has been found. Using the ongoing SDSS IV MaNGA survey, which takes resolved spectroscopy for 10,000 nearby galaxies, Cheung et al. discovered a new class of quiescent galaxies—dubbed “red geysers”—that hosts outflowing winds powerful enough to heat ambient gas and suppress future star formation. These winds are manifested in bisymmetric emission features (in H-alpha, [OII], and other strong lines) and are likely powered by their weakly-accreting supermassive black holes.

To highlight the key characteristics of this class, Cheung et al. focus on a prototypical red geyser, which they nicknamed “Akira”—a reference to the critically-acclaimed manga comic of the same name, and in homage to the MaNGA survey and the lead author’s current institute in Japan (Kavli IPMU). Akira is undergoing a minor interaction with another galaxy, which they’ve nicknamed “Tetsuo”—another character in the same manga comic as Akira; the SDSS image of the interaction is shown in panel a of the figure below, which is reproduced from the Cheung et al. 2016. According to merger simulations, Tetsuo is depositing cool gas into Akira, which is detected in redshifted Na D absorption (panels d and e). The expected star-formation from this cool gas, however, is absent: Cheung et al. find that the measured star-formation rate of Akira is much lower than what is expected given the amount of cold gas present. Thus something is prohibiting star formation in Akira—what is it?

The image and diagnostic diagrams of "Akira", a prototypical red geyser.

The images and diagnostic diagrams of “Akira”, a prototypical red geyser. 

Inspecting the ionized gas properties of Akira, Cheung et al. find an interesting bisymmetric emission pattern in H-alpha and other strong emission lines (panel c). These emission patterns roughly align with the ionized gas velocity gradient (panel h), suggestive of an outflow. To prove that the ionized gas is in an outflowing wind instead of in a rotating disk, Cheung et al. had to disprove the latter case. Using the stellar dynamics of Akira (panels f and g), they obtain a tight constraint on its gravitational potential, from which they are able to predict the ionized gas kinematics in the case of a regularly rotating disk. They find that the observed ionized gas kinematics are significantly higher than the predicted ionized gas kinematics (panel j), indicating that the ionized gas is not under the influence of gravity alone.

Ruling out the disk interpretation, Cheung et al. developed a qualitative wind model that reproduces many of the features of the data, including the ionized gas velocity field and the ionized gas velocity dispersion field. They theorize that this outflowing wind is likely powered by the weakly-accreting supermassive black hole at the center of Akira, which is detected as a central radio point source in the FIRST survey and in followup Jansky VLA observations. They calculate that the energetic output from this low-luminosity active galactic nuclei (AGN) is sufficient to power this outflowing wind, which in turn, has enough energy to counterbalance the cooling of both the warm and cool gas within Akira, and thereby suppress star formation.

While Akira is an ideal case-study, perhaps the most exciting aspect of this study is the fact that there are many more red geysers. Red geysers make up about 10% of quiescent galaxies at moderate stellar masses (2×1010 solar masses), which could have important implications on the duty cycle of this kind of supermassive black hole feedback. Moreover, because they are relatively common, red geysers may exemplify how typical quiescent galaxies maintain their quiescence.

An artist view of the universe 艺术家眼里的宇宙

/ Zheng Zheng / 1 Comment

Recently, a Chinese artist, Jian Yang, organized his personal exhibition in Beijing, China. The exhibition is called “the beginning of infinity” and one of his art pieces showed in this exhibition has a component made of an SDSS plate.

最近中国的一位艺术家杨健在北京进行了一次个人艺术展。这次展出的名字叫 “无穷的开始”，而其中的一件艺术品是利用了SDSS的一块光纤插板做成的。

The room holding the exhibition was designed as a maze. The art piece with the SDSS plate was placed at the center of a maze. It is named “The Universe” and the idea came from an old fairy tale: The earth is a big whale and the sky is a huge elephant. If you could find a leg of the elephant and climb up along the leg, then you could grab the stars. In the artist’s view, the SDSS telescope is trying to capture and analyze the starlight. So he combined science and the fairy tale by putting the SDSS plate at the bottom of the flying elephant’s leg, which means the plate could help us climb up and reach the stars.

展览的场地被别出心裁的设计成了迷宫的模式。而这件包含SDSS光纤插板的艺术品就被放置在迷宫的正中央。作品的灵感来源于艺术家小时候听到的神话故事：说大地是一只鲸鱼，宇宙是一只巨大的大象，如果你能找到大象的腿，往上爬就能抓到星星。对于艺术家来说，SDSS项目就是在做捕获分析星光的工作。杨健把SDSS光纤插板当作一只升腾起来的大象的脚底板，通过这种形象的建构来联合中国与国际，神话和科学。

 

The room holding the exhibition was designed as a maze.

The room holding the exhibition was designed as a maze. 整个展览场地被设计成一个迷宫的形式。

 

The art piece with an SDSS plate (plate# 3939).

The art piece with an SDSS plate (plate# 3939). The plate （编号3939） is placed at the bottom of an elephant’s leg. 用SDSS光纤插板做成的艺术品. SDSS的板子被当做大象的脚底板。

 

The art piece viewed from the bottom.

The art piece viewed from the bottom. 从下面看这件艺术品。

Tweep of the Week: Patrick Gaulme

/ Jennifer Johnson / Leave a comment
Still Life of Patrick Gaulme with Telescope. Credit: Arl Cope

Still Life of Patrick Gaulme with Telescope. Credit: Arl Cope

Our @sdssurveys Tweep of the Week for the week of March 27th is Patrick Gaulme, stellar and planetary astronomer and part of the observing team for SDSS. Patrick will be at Apache Point Observatory for part of this week, taking observations for @MaNGASurvey, @APOGEEsurvey, and @eBOSSurvey. Fingers crossed for clear skies, low humidity, and calm winds. Now we also turn the blog over to Patrick to introduce himself:

 

Hello, my name is Patrick Gaulme, I have been an SDSS astronomer for about two years. I am also a researcher in the field of seismology of stars and giant planets. I am science PI of a NASA-ADAP grant to study eclipsing binaries detected by the NASA Kepler space telescope, and PI of several observation projects with K2, the resuscitated version of Kepler.

I am involved in developing techniques and methods to measure planetary atmospheric dynamics with Doppler imaging in the visible domain. For this I am science PI of the NASA-EPSCoR granted JIVE in NM instrument project, which is a Doppler imager aiming at detecting oscillations of Jupiter and Saturn and measure winds of thick atmospheres in our solar system.

Tweep of the Week: Audrey Oravetz

/ Karen Masters / Leave a comment

This week our @sdssurveys Twitter account will be run by SDSS observer, Audrey Oravetz. Audrey is part of the staff of observers and fiber optic technicians (the people who plug optical fibers into the plates) working for SDSS at our survey telescope in Apache Point, New Mexico (our telescope is neither automated, nor robotic, despite the common misconception!).

Audrey Oravetz

SDSS Observer, Audrey Oravetz (she’s definitely not a robot).

Here’s Audrey introducing herself in her own words:

Hello. My name is Audrey Oravetz and I have worked as an observer for the 2.5m SDSS telescope for the past nine years. It was always a dream of mine to work at a high-ranking observatory. I enjoy working alongside my colleagues to output a high quantity of quality data for the SDSS projects.

I graduated from the University of Colorado at Boulder in 2007 with a B.A. in Astrophysics and graduated from NMSU with a M.S. degree last summer. My thesis (under the supervision of Dr. Rene Walterbos (NMSU)) was centered around the study of ionizing H-alpha photons within two star formation nebulae, NGC346 and NGC602, within the SMC.

A Docufeest in New York.

/ Karen Masters / 3 Comments

This week many of the Key People in SDSS-IV have been meeting in New York to get a good start on the Documentation that is needed to accompany the upcoming Thirteenth Data Release (DR13) of the surveys (scheduled for July 2016).

Docufeest (scientists working on laptops)

SDSS-IV scientists hard at work at Docufeest.

Here a storify from Twitter of all the documentation fun we have been having at Docufeest. You will have to wait to see the updated website until the summer.