After a successful pre-shipment review last Friday, the Instrument and Science Teams of APOGEE have been given approval to ship the nearly-completed spectrograph to the Apache Point Observatory in three weeks. This approval was based upon completion of planned laboratory integration and testing to demonstrate that the instrument will ultimately meet science requirements; a list of open items and on-site commissioning activities remain to be completed before the instrument is fully ready for the “official” start of survey operations. The most critical identified open items are fine-tuning detector focus and correcting some astigmatism identified during lab testing. Additional integration challenges await the Teams when the instrument begins on-sky commissioning. First Light on the Sloan 2.5m telescope is anticipated 2-3 weeks after the instrument is shipped. Stay tuned.

APOGEE Spectrograph nears end of integration and testing.

Red, Green, and Blue Detectors recording infrared sunlight on 300 individual fibers. The spectra cover from 1.69 to 1.51microns (left to right).

Full suite of fibers installed for current round of testing. Each white bundle contains 30 fibers and terminates in a polished v-groove block (at lower right) where starlight enters the instrument.

APOGEE, the survey, coming soon!

Science Watch has provided a commentary on the SDSS-II paper by Reid et al. (2010) cosmology paper which has been classed as a “fast breaking paper” because of the rate of citations the paper has received already. Beth Reid provides a short summary of the paper and discusses the success of the SDSS.

The BOSS collaboration has now finished their meeting in Cloudcroft, which included several trips to nearby Apache Point Observatory to see the Sloan Digital Sky Survey (SDSS) in action (and even help with observations). We include below a series of photos (taken by Emmanuel Rollinde from IAP) showing the BOSS scientists getting to grips with BOSS and the SDSS telescope

BOSS scientist hard at work at the Lodge in Clouldcroft

Of to work at APO; hard nights of observing in front of them!

First, need to get a plate (on top) to observe, which are installed in cartridges (one seen at the bottom)

Next, mark where all the fibers go in the plate holes

Plug the fibers in the holes, and then you're ready

Stephen Bailey in front of the SDSS telescope before it is opened

Fill up the (green) BOSS spectrographs with liquid nitrogen to keep the detectors cool during the night

As the sun sets, open the telescope and prepare to start taking spectra

Finally, we provide below two video showing the APO observers and BOSS scientists getting ready for a nights fun. Thanks to Emmanuel Rollinde and Stephanie Snedden for them.

[youtube http://www.youtube.com/watch?v=Kjvt7MVb32U&w=640&h=390]

[youtube http://www.youtube.com/watch?v=u-I9N80V47U&w=480&h=390]

The SDSS-III BOSS is holding their collaboration meeting in Cloudcroft, New Mexico at the moment. Cloudcroft is the nearest town to the Apache Point Observatory, where the Sloan Digital Sky Survey (SDSS) telescope is located. The meeting has nearly 100 scientists, from across the world, and each evening these scientists have the opportunity to visit APO and see the SDSS telescope in action. For many of them, it is the first time they have seen the telescope that is collecting their data.

Below are two photos from the first day of the meeting, showing BOSS astronomers arriving at the Lodge in Cloudcroft (where the meeting is being held), and then a photo showing them hard at work. Photos taken by John Parejko.

Bob Nichol (SDSS-III Spokesperson) gave an extended radio interview to the Planetary Society about the SDSS-III survey. The interview which lasts over 10 mins includes a discussion about the DR8 terapixel image, Galaxy Zoo and public interaction with Science, and the SDSS-III survey.

The interview can be downloaded here

On the frigid winter night of January 22, 2011, the APOGEE project had its first successful “observing run”. With one of the instrument-installed APOGEE fiber bundles passed through the window of the instrument assembly lab at the University of Virginia (UVa) and then coupled to a modified 10-inch Newtonian telescope just outside, APOGEE took its first spectra of other stars, as well as the planet Jupiter and the Orion Nebula.

The 10-inch telescope modification, a project of first year UVa graduate student Ben Breslauer, uses a dichroic to split optical light, sent to the Newtonian focus for acquiring and guiding objects by eye, from infrared light, sent to the prime focus where fibers in a special “mini-plugplate” receive the light to send on to the APOGEE instrument. The telescope is a scaled down version of the Sloan 2.5-m telescope, with the same f/ratio but 1/10 the diameter. With this arrangement, the 10-inch telescope sees the same diffuse background flux as expected at Apache Point and can, in principle, observe stars 5 magnitudes brighter than the 2.5-m telescope to the same signal-to-noise. But to make the acquisition and guiding easier and to ensure that fibers receive a steady stream of light, the telescope is actually used with the star images out of focus. Nevertheless, many bright and interesting astronomical objects are within easy reach of the system.

Ben Breslauer, coupling one of the 40-meter long APOGEE fiber runs from the instrument to a fiber ``harness" attached to the telescope, with 30 individual fibers plugged into a mini fiber plugplate at the prime focus of the 10-inch telescope. The fibers are arranged to span almost a 1.5 degree field of view

The goal of the 10-inch telescope project is to obtain data for assessing the APOGEE instrument performance, guiding and testing the APOGEE data reduction software pipelines, and understanding the properties of the near-infrared sky background at APOGEE’s high resolution. On the first night of observation, stars from the famous “Winter Hexagon” were observed. Interestingly, the Winter Hexagon (plus Betelgeuse, in the center of the Hexagon) provides a remarkably diverse range of spectral types useful for assessing the broad range of star temperatures that APOGEE will explore in its survey of the Milky Way. The APOGEE science team is now analyzing these important early data in a variety of ways to understand the infrared “airglow”, the spectrograph throughput, and the challenges of observing with an instrument providing such rich spectral information on stars.

A portion of the APOGEE spectra collected with the 10-inch telescope in January, showing the large diversity of spectral types in the Winter Hexagon. The top spectra, with the richest density of lines, are most representative of the expected typical APOGEE spectra (most targets will be of G, K and M spectral type). The wavelengths shown span less than 1/3 of the total APOGEE spectral region. Image by Carlos Allende-Prieto and David Nidever

The APOGEE instrument team, eagerly awaiting the first APOGEE night time spectra after their dogged and successful efforts to get the spectrograph to this point in so short a time (the APOGEE Critical Design Review was in August 2009). APOGEE instrument scientist John Wilson is in the foreground, on the right, standing next to David Nidever, who tirelessly worked to get the software reduction pipeline ready to work on the data. In the background are team members Mike Skrutskie (head of the instrument lab), Bob O'Connell, Matt Nelson, and Fred Hearty (project manager), running the instrument just outside the APOGEE assembly room

APOGEE team member Steven Majewski, guiding an exposure of Rigel in 13F, breezy weather conditions.

APOGEE observed its first astronomical object on Jan 17th 2011 using the full optical system of the instrument, from fibers to the CCDs. This is a major milestone for one of the largest infra-red spectrographs ever built. Soon the instrument will be shipped to Apache Point Observatory for installation and integration with the SDSS telescope; stay tuned for more data from APOGEE.

The two images below show the solar spectrum observed by APOGEE. The first is the raw data taken from the CCD detectors; the dark grey bands are four groups of 30 fibers (or spectra) each, i.e., 120 spectra of the Sun in total. The second image is a plot of the extracted, one-dimensional spectrum of the Sun showing the infrared brightness of sunlight as a function of wavelength. The data still need calibrating but the many features around 1800, 2800 and 3000 pixels (x-axis) in the spectrum are well-known absorption bands caused by methane and cardon dioxide in our atmosphere. The drops to zero in the spectrum (at 2100 and 4400 pixels) are caused by gaps between the CCD detectors and are therefore not a real features in the Sun spectrum.

Raw data from APOGEE of the Sun

Solar spectrum. First astronomical light seen by APOGEE

More photos and technical details at http://www.astro.virginia.edu/~jcw6z/firstlab/ Congratulations to the APOGEE team!

Benjamin Clark, a high school student from Pennsylvania, has won the $100K Siemens Science award for 2010.

http://www.siemens-foundation.org/en/competition.htm

Ben has worked with Cullen Blake at Princeton University on a project related to low-mass binary stars in SDSS data. Ben used the individual 15-minute spectra of SDSS stars to search for very short period binary systems. He then conducted a Monte Carlo simulation to estimate the efficiency with which such systems can be detected and estimated their overall rate of occurrence.

Astronomers release the largest color image of the sky ever made

We provide here the AAS press release and supplementary material and links.

This past week the APOGEE hardware team jumped another hurdle by installing the slithead and the first 120 fibers into the APOGEE instrument. These are the so-called “long-links”, which are 40 meters long and connect the spectrograph (in a separate room) to the SDSS telescope.

Four spools of bundled fibers (30 per "cable" giving 120 in total) containing the fully manufactured long-links. They are being fed into the cryostat assembly clean tent.

The fibers are routed through the cryostat wall, looped through cooling trays, and then held securely in place with the s-tracks shown before reaching the spectrograph slithead

Close up of the slithead. After passing through the ends of the s-tracks (at upper left) the bare fibers (copper-colored) are splayed out and terminated within grooved blocks that are aligned to make sure the end of each fiber is in its proper location. The image shows the first three blocks (90 total fibers) in place.

SDSS was featured on the BBC “Joy of Stats” programme made by Wingspan Productions . Connie Rockosi (SDSS-III SEGUE-II Survey PI) was interviewed about how discoveries are made in the wealth of SDSS data, all freely available on the internet.

2.5m Observing Log, 12/3/2010 Night Observers: Audrey Simmons, Dmitry Bizyaev

A “model” SDSS-III night: seeing ~ 1″, clear sky, ALL plates plugged (8) were finished from scratch.

The key to all of the SDSS spectroscopic surveys has been multiplexing at an unprecedented scale. The original SDSS spectrographs were fed by fiber plugplates with 640 optical fibers. For the Baryon Oscillation Spectroscopic Survey (BOSS) of SDSS-III, this number was upped to 1000 fibers per plate. Under excellent conditions, a complete BOSS observation takes about an hour, including three fifteen minute “science exposures,” calibration observations, and the time required to swap one plugplate cartridge for another on the back of the telescope.

The light of sunset comes through a BOSS cartridge attached to the bottom of the APO 2.5-m telescope (still in its enclosure). Strands visible in silhouette are individual optical fibers that transmit the light of BOSS targets from holes in the fiber plugplate to the spectrographs, which are themselves mounted on the back of the telescope.

When the seeing isn’t needle-sharp or a thin layer of cirrus obscures the sky, it takes more exposures to measure the redshifts and absorption spectra of the faint galaxies and quasars that are the targets of BOSS. Many nights have intervals of clouds or poor seeing, and often there are holdover plates that were observed but not completed the previous night.

But every once in a while, things are perfect, like the night of December 2, 2010. Eleven hours, eight plates, every one done from start to finish. By the morning of December 3, BOSS was richer by 8,000 spectra, the largest one night haul in the history of the SDSS.

Of course, observing eight plates in a night means that our fiber plugging specialists have 8,000 new tasks for the next day. We have placed a rush order for extra liniment. A ninth BOSS cartridge went into service on the night of December 3 (!), so when the next perfect night arrives, we can aim for a clean 9,000.

Congratulations to the SDSS-III observing and telescope team.

Written by David Weinberg

The MARVELS team have published the discovery of a new short-period brown dwarf candidate around the star TYC 1240-00945-1. Below is the phased radial velocity curve TYC 1240-00945-1 with the Keplerian orbit solution. The MARVELS discovery data is in blue, with confirmation data in red (HET data) and purple (SMARTS). The bottom panel shows the residuals between the data points and the orbital solution.

radial velocity curve of MARVELS-1b

Above is the first spectrum taken with the SDSS-III APOGEE spectrograph, that for a krypton discharge lamp.

This spectrum was made under warm conditions and using a InGaAs detector with pixels two times larger than the actual APOGEE detectors will deliver. A series of separate images were taken, stepping along the dispersion direction in the spectrograph focal plane, and were then mosaic’ed together to make this final image. Several examples of these individual images are shown in the postage stamps in the upper corners. The lines in the spectrum are color coded by the final APOGEE detector on which they are expected to fall (blue, middle, red).

Analysis of this spectrum (by David Nidever), although undersampling the spectrograph resolution, suggests that the instrument is performing to specification.

Congratulations to the hardworking instrument team for this great progress!