Image Gallery

The APOGEE survey has revealed a number of new highly magnetic stars that feature interesting spectral features.

Distribution of the Alpha-elements in different regions of the Galaxy.

APOGEE 2 Globular Cluster Anti-Correlations for 31 globular clusters. Adapted from S. Meszaros et al. 2020

Star Formation Histories of Massive Dwarfs in APOGEE2 (Figure 9 of Hasselquist et al. 2021)

Hertzsprung-Russell diagram for all MaStar targets with good quality spectra based on Gaia EDR3 photometry, Bailer-Jones et al (2021) distance, and Green et al. (2019) 3D dust map.

The Raw Selection Function for APOGEE DR16, showing the fraction of stars observed in the short cohort as a function of sky position. Figure by Jo Bovy.

A Lomb-Scargle periodogram derived from the APOGEE radial velocity data of Eclipsing Binary, KIC 2161623. The maximum power occurs at 2.28 days, which is taken as the period of the system. Figure courtesy of H. Lewis.

Snapshot during a session in La Serena in the preparations for APOGEE-2S operations.

The APOGEE-2S "Wrap Party" at the conclusion of the APOGEE-2S Observations in January 2021.

Observatories in the Northern or Southern hemispheres provide only a partial view of the Milky Way. For APOGEE to observe the full Milky Way, it requires telescopes in both hemispheres. Background image from 2MASS.

Schematic identifying the major components of the Milky Way in the infrared sky. Figure by R. Beaton, Background Image from 2MASS.

SDSS-IV team meeting from the 2017 Collaboration Meeting in Santiago, Chile. SDSS-IV included Chilean institutions for the first time in SDSS history.

APOGEE-1 observations overlaid on an artist's impression of the Milky Way galaxy. The points are color-coded by their total metallicity, with blue stars the most metal poor and red stars the most metal rich. Figure from Majewski et al. 2017, their figure 25.

The final field plan from APOGEE-1 as released in DR12. Background image from 2MASS.

ASPCAP spectral windows for the 15 APOGEE chemical elements along with examples of APOGEE sky (black), telluric (blue, red, and green), and stellar spectra (orange). To aid visibility, the spectral windows are broadened by ±30 km s−1, and all weights are set to the same value. From Garcia-Perez et al. 2015, their figure 4.

Organization of observed targets in plate designs and on physical plates, using the field 180+04 as an example. This field has 12 anticipated visits, which are covered by four designs (indicated by blue, yellow, green, and orange). Each design has stars from one of four short cohorts (S1, S2, S3, S4), one of two medium cohorts (M1, M2), and the long cohort (L); that is, stars in the long cohort appear in all four designs, and stars from the medium cohorts appear in two designs. At least one plate is drilled for each design, and some designs (here, the first two) are drilled on multiple plates. Most frequently, this occurs when a field is to be observed at different hour angles (HAs), as in this example. Figure from Zasowski et al. 2013, their figure 1.

The “first light” observations for the APOGEE South spectrograph. The dots show stars whose spectra were observed by APOGEE. Some example spectra are shown (colors are representative only, as APOGEE spectra are in the infrared).
The first light observations included spectra of supermassive stars in the Tarantula Nebula. This nebula in the Large Magellanic Cloud is forming stars more rapidly than any other region in our Local Group of galaxies. It can only be seen from the Southern Hemisphere, underscoring the importance of APOGEE South’s location. The spectrograph will allow us to study the chemistry and evolution of the stars in the nebula in greater detail than ever before.
Tarantula Nebula image from Herschel/Spitzer

MaNGA science team at the 2019 team meeting (April 2019, Oxford, England)

An artist’s rendering of how the iron content of a star can impact its planets. A normal star (green label) is more likely to host a longer-period planet (green orbit), while an iron-rich star (yellow label) is more likely to host a shorter-period planet (yellow orbit). Click on the image for a larger version.

Sunset at the SDSS 2.5m telescope at Apache Point Observatory (March 2014).

Part of the SDSS-IV/MaNGA commissioning team at Apache Point Observatory (March 2014).

Team photo of APOGEE-1 during a Team Meeting at Texas Christian University.

APOGEE-2 Team Meeting at the Observatories of the Carnegie Institution for Science.

DR17 APOGEE field map where the fields are color-coded by the APOGEE sub-survey. APOGEE-1 in cyan, APOGEE-2N in blue, and APOGEE-2S in red. Figure by C. Hayes. Background image from 2MASS.

From Majewski et al. 2017, Figure 14: Portion of a raw 2D APOGEE image from observations of a bulge field. The horizontal stripes correspond to individual stellar spectra. Vertical bright bands correspond to airglow features at the same rest wavelength in each spectrum, whereas absorption features at the same horizontal position from spectrum to spectrum correspond to telluric absorption features. Also obvious are variations in the expression of stellar atmospheric absorption features from star to star, evidenced by their varying strengths due to temperature and chemical composition differences, as well as changing relative positions due to Doppler shifts. Fiber assignments were managed by color-coding fiber holes in the plugplates (see Figure 13) and the fiber optic jackets at the telescope end to correspond to stars in each field sorted into three brightness groups (bright, medium, faint). These fibers were sorted at the spectrograph slit head into a repeating pattern of faint−medium−bright−bright−medium−faint to minimize the contamination of any given spectrum by the PSF wings of a much brighter spectrum in an adjacent fiber. This management scheme gives rise to the brightness modulation pattern apparent in this image.

Comparison of plates used for the APOGEE-N instrument (left) and the APOGEE-S instrument (right). Both plates are the same physical size, but, due to the differing telescope f/ ratios have different plate scales. APOGEE-S plates are machine-marked when APOGEE-N plates are marked by hand. APOGEE-S plates have two obscured regions that are used to place cameras, whereas the obscured regions in the APOGEE-N plate do not require physical hole (a central post is mounted in the center of the plate).

APOGEE-2S observers both plug plates and take observations, typically alternating between roles during the observing runs. Here an observer prepares a cartridge by connecting the fibers to the proper plate holes. (Photo courtesy of A. Almeida)

Images of the fibers in each of the MaNGA IFUs ranging from 7 to 127 fibers. Figure is from Drory et al. (2015)

Members of the APOGEE Team work on preparing infrastructure for the APOGEE-S instrument at Las Campanas Observatory. This image is taken inside of the du Pont 2.5 meter dome. Photo by Sanjay Suchak.

Plugging an APOGEE plate at Apache Point Observatory.

An APOGEE-S cartridge is loaded onto the telescope for observations.

The APOGEE Instrument Team works on running the APOGEE-S fiber train through the du Pont dome. Photo by J. Wilson

The APOGEE-2 instrument at LCO

The logo of the SPIDERS sub-survey (part of eBOSS in SDSS-IV)

MaNGA tiling, status and prediction for future observation published in DR16 (Aug 2019)

Kepler 102 (left): Earth-like, dominated by olivine minerals; Kepler 407 (right): dominated by garnet, less likely to have plate tectonics

SDSS-V will be carried out in both hemispheres, at Apache Point Observatory (APO) in the USA and Las Campanas Observatory (LCO) in Chile. Multi-object fiber spectroscopy will be obtained with two 2.5m telescopes, each feeding a near-infrared APOGEE spectrograph and an optical BOSS spectrograph, for the Milky Way Mapper and Black Hole Mapper programs. The Local Volume Mapper will make use of smaller telescopes at APO and LCO to perform its optical integral-field spectroscopy.

Extinction-corrected color-luminosity diagram for the DR15 version of the MaStar Library, color-coded by metallicity (click to enlarge). The photometry in this figure are in SDSS bands. The derivation of the absolute magnitudes are based on distances computed by Bailer-Jones et al. (2018) using parallax from Gaia DR2.

A plot of specific starformation rate (SFR/M*) against stellar mass (M*) for galaxies analysed in the DR15 version of Pipe3d. Each galaxy is shown as a map of the kinematics traced by Halpha line.

Kepler 102 (left): Earth-like, dominated by olivine minerals; Kepler 407 (right): dominated by garnet, less likely to have plate tectonics.

Screenshot of summary data SN2011V

Map of DIB absorption strength from SDSS infrared and optical spectroscopy (Lan et al. 2015; Zasowski et al. 2015).

ARCSAT telescope structure, with the Sloan Telescope housing in the background.

A galaxy inside a pink hexagon, which shows the coverage area of a MaNGA IFU

MaNGA written in galaxies. Write your own message in the sky: http://writing.galaxyzoo.org/

Artist conception of the Milky Way Galaxy, with location of APOGEE-1 stars.

Miliani Middle School Teacher, Kari Caldeira-Silva (center), collecting her SDSS plate (number 6274) at the IAU meeting in Honolulu, Hawaii from Kate Meredith (left) and Karen Masters (right)

An all sky plot showing the APOGEE DR12 Coverage for both Survey and Commissioning Data.

An all-sky plot showing the planned for APOGEE DR13 survey.

The assembled central optics (two dispersive elements and the dichroic).

The 2-ton APOGEE-N instrument is lowered to the concrete pad in front of its room in the warm building next to the Sloan Foundation 2.5-meter telescope.

Diagram of the APOGEE-N gang-connector system (fiber routing and the 300-fiber gang connector) which allows for a facile change of the fiber connections between the instrument and the various cartridges. Slide from J. Wilson.

A SDSS fiber optic plug plate showing the markings used to plug fibers.

A wide angle view of the patch of SDSS imaging containing "Hanny's Voorwerp", the blueish nebula next to galaxy IC 2497 at lower left of the image.

Exemplar APOGEE spectra for stars of O, B, A, F, G, K, and M spectral types. Figure by S. Chojnowski.

APOGEE-2 will extend the reach of the SDSS by using both the Sloan Foundation Telescope at Apache Point Observatory and the Irénée du Pont Telescope at Las Campanas Observatory in Chile.

A telescope in each hemisphere means that APOGEE-2 will be able to see the entire Milky Way. The new Chilean telescope will offer an excellent view of the galactic central regions.

Image credit: Dana Berry / SkyWorks Digital Inc. and the SDSS collaboration

eBOSS maps the distribution of galaxies and quasars from when the Universe was 3 to 8 billion years old, a critical time when dark energy started to affect the expansion of the Universe. At higher redshifts, during a time when the Universe was matter-dominated, eBOSS uses the Lyman-alpha forest to map out the matter distribution. Image Credit: Dana Berry / SkyWorks Digital Inc. and the SDSS collaboration.

The new SDSS will measure spectra at multiple points in the same galaxy, using a newly created fiber bundle.

The Sloan Foundation Telescope (top left) leads to a close-up of the fiber bundle tip so that each fiber can see a different part of the same galaxy (bottom right).

The image from the Hubble Space Telescope (bottom right) shows one of the first galaxies the new SDSS has measured. Spectra from different parts of ths galaxy (top right) show how how the center of the galaxy differs from its outer regions.

The SDSS “Orange Spider”. This illustrates the wealth of information on scales both small and large available in the SDSS I/II and III imaging. The picture in the top left shows the SDSS view of a small part of the…

Stacked spectra of more than 46,000 quasars from the SDSS; each spectrum has been converted to a single horizontal line, and they are stacked one above the other with the closest quasars at the bottom and the most distant quasars at the top.
Credit: X. Fan and the Sloan Digital Sky Survey.

The star cluster M13 as seen by the SDSS

The SDSS's "Field of Streams" map shows structures of stars in the outer Milky Way

The ultra-faint Milky Way Companion galaxy Leo I

The bright spiral galaxy M51 and its fainter companion

The SDSS's map of the Universe. Each dot is a galaxy; the color is the g-r color of that galaxy .

The Irenee du Pont Telescope at Las Campanas Observatory in Chile

SDSS legacy imaging of the bright spiral galaxy, Messier 81 (Bode’s Galaxy). This galaxy lies about 12 million light years away in the constellation Ursa Major.

Spectrum of a Quasar

The Sloan 2.5m Telescope

SDSS Imaging Camera.

The SEGUE-1 fields are displayed in blue and the SEGUE-2 are in red. The map is in Galactic coordinates (credit: M. Strauss).

SDSS stellar map of the Northern sky, showing trails and streams of stars torn from disrupted Milky Way satellites. Insets show new dwarf companions discovered by the SDSS

Milky Way science: using SEGUE data with SSPP parameter estimates to determine the radial metallicity gradient of the Galactic disk (Cheng et al. 2012)

A randomly selected spectrum from the DR10 BOSS data, showing absorption (red) and emission (blue) lines.

Comparison of the power spectrum of SDSS-II LRGs and BOSS DR9 CMASS galaxies. Solid lines show the best-fit models. From Anderson et al. 2012.

An illustration of the concept of baryon acoustic oscillations, which are imprinted in the early universe and can still be seen today in galaxy surveys like BOSS

The APOGEE-2 survey footprint, overlaid on an infrared image of the Milky Way. Each dot shows a position where APOGEE obtains at least 250 stellar spectra.

Planned eBOSS coverage of the Universe

The planned APOGEE-2 survey area overlain on an image of the Milky Way. Each dot shows a position where APOGEE-2 will obtain stellar spectra. Figure by P. Frinchaboy.

An illustration of the footprint of a 127 fiber MaNGA bundle overlaid on an image of a galaxy.

An image of the face of a 127 fiber MaNGA IFU.

A smaller version of this image also exists.