The Carnegie Hubble program is an ongoing comprehensive effort that has a goal of determining the Hubble constant, the expansion rate of the universe,  to a systematic accuracy of 2%. As part of this program, astronomers are obtaining data at the 3.6 micron wavelength using the Infrared Array Camera (IRAC) on Spitzer Space Telescope. The team has demonstrated that the mid-infrared period-luminosity relation for Cepheids, variable stars used to determine distances and the rate of the expansion,  at 3.6 microns is the most accurate means of measuring Cepheid distances to date. At 3.6 microns, it is possible to minimize the known remaining systematic uncertainties in the Cepheid extragalactic distance scale. The team has  undertaken three independent tests of the sensitivity of the mid-IR Cepheid Leavitt Law to metallicity—the  relative chemical abundances of the stars—which when combined will allow them to zero in on the  effect.

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Alan Boss
Alan Boss selected as AAS Fellow
January 14, 2022

Washington, DC— Carnegie’s Alan Boss was named one of 23 new Fellows of the American Astronomical Society. The honorees were chosen for their “extraordinary achievement and service” to the field.

Boss, whose contributions to the fields of astronomy and astrophysics are numerous, was specifically recognized for “innovative theoretical investigations of the formation of stars and exoplanets” as well as “tireless leadership within the exoplanet exploration community in ensuring that NASA executes a credible and successful exoplanet program.”

The AAS fellowship program began in 2020 and its members include professional astronomers

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Mars mosaic courtesy of NASA.
Martian meteorite’s organic materials origin not biological, formed by geochemical interactions between water and rock
January 13, 2022

Washington, DC—Organic molecules found in a meteorite that hurtled to Earth from Mars were synthesized during interactions between water and rocks that occurred on the Red Planet about 4 billion years ago, according to new analysis led by Carnegie’s Andrew Steele and published by Science.  

The meteorite, called Allan Hills (ALH) 84001, was discovered in the Antarctic in 1984 and is considered one of the oldest known projectiles to reach Earth from Mars.  

“Analyzing the origin of the meteorite’s minerals can serve as a window to reveal both the geochemical processes occurring early in Earth’s history and Mars’ potential for

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Milky Way and stellar streams, Credit: James osephides and S5 Collaboration.
The Milky Way’s feeding habits shine a light on dark matter
January 11, 2022

Pasadena CA—A new map of a dozen associations of moving stars—called stellar streams—orbiting within the Milky Way’s halo has brought astronomers one step closer to revealing the properties of the dark matter enveloping our galaxy and shaping the universe.  Accepted for publication in The Astrophysical Journal, the map was produced by an international collaboration of astronomers, including several current and former Carnegie scientists.

“Stellar streams are the shredded remains of neighboring small galaxies and star clusters that are torn apart by the Milky Way,” explained Carnegie’s Josh Simon, a co-author on the paper. “These

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Artist conception. Credit: NASA GSFC/CIL/Adriana Manrique Gutierrez
Carnegie astronomers will use JWST to probe fundamental questions about our cosmos
December 23, 2021

Washington, DC—A a perfect seasonal gift to astronomers around the world—the James Webb Space Telescope successfully launched on the morning of December 25.  This next-generation space telescope will drive a new era of discovery—with capabilities that will complement the upcoming era of extremely large ground-based telescopes, including the Giant Magellan Telescope under construction at Carnegie’s Las Campanas Observatory in Chile.

Several Carnegie astronomers will be among the first to lead projects using data from JWST observations. Their planned investigations will span the breadth of expertise at our Observatories and Earth and Planets Laboratory

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Vera Rubin Fellowship

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. 
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The Earthbound Planet Search Program

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

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The Giant Magellan Telescope Project

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

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Carnegie Astrometric Planet Search

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/

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Ana Bonaca

Ana Bonaca is Staff Member at Carnegie Observatories. Her specialty is stellar dynamics and her research aims to uncover the structure and evolution of our galaxy, the Milky Way, especially the dark matter halo that surrounds it. In her research, she uses space- and ground-based telescopes to measure the motions of stars, and constructs numerical experiments to discover how dark matter affected them.

She arrived in September 2021 from Harvard University where she held a prestigious Institute for Theory and Computation Fellowship. 

Bonaca studies how the uneven pull of our galaxy’s gravity affects objects called globular clusters—spheres made up of a million

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Peter Gao

Peter Gao's research interests include planetary atmospheres; exoplanet characterization; planet formation and evolution; atmosphere-surface-interior interactions; astrobiology; habitability; biosignatures; numerical modeling.

His arrival in September 2021 continued Carnegie's longstanding tradition excellence in exoplanet discovery and research, which is crucial as the field prepares for an onslaught of new data about exoplanetary atmospheres when the next generation of telescopes come online.

Gao has been a part of several exploratory teams that investigated sulfuric acid clouds on Venus, methane on Mars, and the atmospheric hazes of Pluto. He also

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Anne Pommier

Anne Pommier's research is dedicated to understanding how terrestrial planets work, especially the role of silicate and metallic melts in planetary interiors, from the scale of volcanic magma reservoirs to core-scale and planetary-scale processes.

She joined Carnegie in July 2021 from U.C. San Diego’s Scripps Institution of Oceanography, where she investigated the evolution and structure of planetary interiors, including our own Earth and its Moon, as well as Mars, Mercury, and the moon Ganymede.

Pommier’s experimental petrology and mineral physics work are an excellent addition to Carnegie’s longstanding leadership in lab-based mimicry of the

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Johanna Teske

Johanna Teske became the first new staff member to join Carnegie’s newly named Earth and Planets Laboratory (EPL) in Washington, D.C., on September 1, 2020. She has been a NASA Hubble Fellow at the Carnegie Observatories in Pasadena, CA, since 2018. From 2014 to 2017 she was the Carnegie Origins Postdoctoral Fellow—a joint position between Carnegie’s Department of Terrestrial Magnetism (now part of EPL) and the Carnegie Observatories.

Teske is interested in the diversity in exoplanet compositions and the origins of that diversity. She uses observations to estimate exoplanet interior and atmospheric compositions, and the chemical environments of their formation

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