Stephen Shectman blends his celestial interests with his gift of developing novel telescope instrumentation. He investigates the large-scale structure of the galaxy distribution; searches for ancient stars that have few elements; develops astronomical instruments; and constructs large telescopes. Shectman was the former project scientist for Magellan and is largely responsible for the superb quality of 6.5-meter telescopes. He is now a member of the Giant Magellan Telescope Project Scientists’ Working Group.

 To understand large-scale structure, Shectman has participated in several galaxy surveys. He and collaborators discovered a particularly large void in the galaxy distribution in the early 1980s and subsequently conducted the Las Campanas Redshift Survey (LCRS) using the C100 fiber spectrograph—a device that collects light, disperses it into spectra to reveal the chemistry and other features. The LCRS was the definitive distance survey of the time and showed that the galaxy distribution becomes homogeneous at large scales compared with the strong fluctuations characteristic of the small-scale distribution.

Hydrogen and helium were produced in the Big Bang, but heavier elements came from nucleosynthesis in successive stellar generations. The oldest stars are deficient in heavy elements, what astronomers call metal-poor. In the 1980s, Shectman and George Preston conducted a survey for these objects. Using novel techniques they discovered the majority of known stars with heavy-element abundances less than about 1% of the Sun’s. Shectman has also worked on metal-poor stars in the Hamburg-ESO survey, using Magellan spectrographs to identify and study the best ones in detail.

 Shectman developed a series of photon-counting detectors for faint-object spectroscopy. They were used at Las Campanas and copied by other observatories. He also built the high-resolution echelle spectrograph and the multiobject fiber spectrograph for the 100-inch du Pont telescope. With Rebecca Bernstein, he built the high-resolution echelle spectrograph for Magellan, which has been in service for several years. He is currently working on the Magellan echellette spectrograph, a joint MIT-Carnegie project with Scott Burles (MIT) and Carnegie’s Ian Thompson, and the Magellan Planet Finder, a collaboration with Carnegie’s Paul Butler and Jeff Crane.

Shectman received his B.S. in physics from Yale Univesity and a Ph. D. in astronomy from Caltech where he was also a National Science Foundation fellow. Before joining the Carnegie staff in 1975, he was a postdoctoral fellow at the University of Michigan. For more information see http://obs.carnegiescience.edu/users/shec

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Pan-STARRS image showing the host galaxy of the newly discovered supernova ASASSN-18bt
November 29, 2018

Pasadena, CA—A supernova discovered by an international group of astronomers including Carnegie’s Tom Holoien and Maria Drout, and led by University of Hawaii’s Ben Shappee, provides an unprecedented look at the first moments of a violent stellar explosion. The light from the explosion's first hours showed an unexpected pattern, which Carnegie's Anthony Piro analyzed to reveal that the genesis of these phenomena is even more mysterious than previously thought.

Their findings are published in a trio of papers in The Astrophysical Journal and The Astrophysical Journal Letters. (You can read them here, here, and here.)

Type Ia supernovae are

SDSS/Caltech/Keck
October 11, 2018

Pasadena, CA—Carnegie’s Anthony Piro was part of a Caltech-led team of astronomers who observed the peculiar death of a massive star that exploded in a surprisingly faint and rapidly fading supernova, possibly creating a compact neutron star binary system. Piro’s theoretical work provided crucial context for the discovery. Their findings are published by Science.

Observations made by the Caltech team—including lead author Kishalay De and project principal investigator Mansi Kasliwal (herself a former-Carnegie postdoc)—suggest that the dying star had an unseen companion, which gravitationally siphoned away most of the star's mass before it exploded

John Graham
September 24, 2018

Washington, DC—Carnegie astronomer John Graham—who also served during different periods as both Vice President and Secretary of the American Astronomical Society—died at home in Washington, D.C., September 13 after a battle with brain cancer. He was 79.

Graham, who specialized in the observation of young stars and the star formation process in the Milky Way and neighboring galaxies, joined Carnegie’s Department of Terrestrial Magnetism from the Cerro Tololo Inter-American Observatory in 1985. George Preston, who was Director of the Carnegie Observatories at the time Graham came to DTM, also offered Graham a simultaneous five-year adjunct appointment at the

August 9, 2018

Washington, D.C.—Observatories NASA Hubble Postdoctoral Fellow Maria Drout will receive the tenth Postdoctoral Innovation and Excellence Award (PIE). These awards are made through nominations from the departments and are chosen by the Office of the President. The recipients are awarded a cash prize for their exceptionally creative approaches to science, strong mentoring, and contributing to the sense of campus community.

Maria Drout was one of four Carnegie astronomers who, along with colleagues from UC Santa Cruz, provided the first-ever glimpse of two neutron stars colliding last August. She was first author on a Science paper, which measured the changing light from that

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The fund supports a postdoctoral fellowship in astronomy that rotates between the Carnegie Science departments of Terrestrial Magnetism in Washington, D.C., and the Observatories in Pasadena California. 

The Earthbound Planet Search Program has discovered hundreds of planets orbiting nearby stars using telescopes at Lick Observatory, Keck Observatory, the Anglo-Australian Observatory, Carnegie's Las Campanas Observatory, and the ESO Paranal Observatory.  Our multi-national team has been collecting data for 30 years, using the Precision Doppler technique.  Highlights of this program include the detection of five of the first six exoplanets, the first eccentric planet, the first multiple planet system, the first sub-Saturn mass planet, the first sub-Neptune mass planet, the first terrestrial mass planet, and the first transit planet.Over the course of 30 years we have

The Giant Magellan Telescope will be one member of the next class of super giant earth-based telescopes that promises to revolutionize our view and understanding of the universe. It will be constructed in the Las Campanas Observatory in Chile. Commissioning of the telescope is scheduled to begin in 2021.

The GMT has a unique design that offers several advantages. It is a segmented mirror telescope that employs seven of today’s largest stiff monolith mirrors as segments. Six off-axis 8.4 meter or 27-foot segments surround a central on-axis segment, forming a single optical surface 24.5 meters, or 80 feet, in diameter with a total collecting area of 368 square meters. The GMT

Along with Alycia Weinberger and Ian Thompson, Alan Boss has been running the Carnegie Astrometric Planet Search (CAPS) program, which searches for extrasolar planets by the astrometric method, where the planet's presence is detected indirectly through the wobble of the host star around the center of mass of the system. With over eight years of CAPSCam data, they are beginning to see likely true astrometric wobbles beginning to appear. The CAPSCam planet search effort is on the verge of yielding a harvest of astrometrically discovered planets, as well as accurate parallactic distances to many young stars and M dwarfs. For more see  http://instrumentation.obs.carnegiescience.edu/

The Ludington lab investigates complex ecological dynamics from microbial community interactions using the fruit fly  Drosophila melanogaster. The fruit fly gut carries numerous microbial species, which can be cultured in the lab. The goal is to understand the gut ecology and how it relates to host health, among other questions, by taking advantage of the fast time-scale and ease of studying the fruit fly in controlled experiments. 

Nick Konidaris is a staff scientist at the Carnegie Observatories and Instrument Lead for the SDSS-V Local Volume Mapper (LVM). He works on a broad range of new optical instrumentation projects in astronomy and remote sensing. Nick's projects range from experimental to large workhorse facilities. On the experimental side, he recently began working on a new development platform for the 40-inch Swope telescope at Carnegie's Las Campanas Observatory that will be used to explore and understand the explosive universe.

 Nick and his colleagues at the Department of Global Ecology are leveraging the work on Swope to develop a new airborne spectrograph that will be

Experimental petrologist Michael Walter became director of the Geophysical Laboratory beginning April 1, 2018. His recent research has focused on the period early in Earth’s history, shortly after the planet accreted from the cloud of gas and dust surrounding our young Sun, when the mantle and the core first separated into distinct layers. Current topics of investigation also include the structure and properties of various compounds under the extreme pressures and temperatures found deep inside the planet, and information about the pressure, temperature, and chemical conditions of the mantle that can be gleaned from mineral impurities preserved inside diamonds.

Walter

Leopoldo Infante became the director of the Las Campanas Observatory on July 31, 2017.

Since 2009, Infante has been the founder and director of the Centre for Astro-Engineering at the Chilean university. He joined PUC as an assistant professor in 1990 and has been a full professor since 2006. He was one of the creators of PUC’s Department of Astronomy and Astrophysics, and served as its director from 2000 to 2006. He also established the Chilean Astronomical Society (SOCHIAS) and served as its president from 2009 to 2010.

Infante received his B.Sc. in physics at PUC. He then acquired a MSc. and Ph.D. in physics and astronomy from the University of Victoria in