SETI Alumni: Portrait of Sarah Blunt

SETI Institute GPI group from left to right: Eric Nielsen, Franck Marchis, Jasmine Garani, Sarah Blunt, and Clement Chalumeau
SETI Institute GPI group from left to right: Eric Nielsen, Franck Marchis, Jasmine Garani, Sarah Blunt, and Clement Chalumeau (credit: F. Marchis/SETI Institute)

Sarah Blunt, REU student class of 2015, is today a full member of the Gemini Planet Imager Exoplanet Survey. Together with SETI researcher Eric Nielsen and Franck Marchis, she has developed an innovative method to fit the orbits of directly imaged exoplanets. She has published her work in Astronomical Journal and is a recipient of an NSF Graduate Research Fellowship that will fund her graduate school. Here her story.

Observing planet formation at close range: Gemini Planet Imager’s view of the TW Hya disk

Investigations of star and planet formation have long focused on the rich stellar nurseries of Taurus, Ophiuchus, Chamaeleon, and a handful of similarly nearby (but lower mass) molecular clouds. These regions, which lie just beyond 100 pc, are collectively host to hundreds of low-mass, pre-main sequence (T Tauri) stars with ages of a few million years and less. They hence provide large samples of stars with orbiting circumstellar disks that span a wide range of evolutionary stages.

Thoughts on GPI

In a major breakthrough for exoplanet discovery and exploration, the Gemini Planet Imager (GPI) is proving to be one of most powerful and effective instruments ever invented for directly imaging planets in orbit around other stars.

An artistic conception of the Jupiter-like exoplanet, 51 Eri b, seen in the near-infrared light that shows the hot layers deep in its atmosphere glowing through clouds. Because of its young age, this young cousin of our own Jupiter is still hot and  carries information on the way it was formed 20 million years ago.  credits: Danielle Futselaar & Franck Marchis, SETI Institute
An artistic conception of the Jupiter-like exoplanet, 51 Eri b, seen in the near-infrared light that shows the hot layers deep in its atmosphere glowing through clouds. Because of its young age, this young cousin of our own Jupiter is still hot and carries information on the way it was formed 20 million years ago.
credits: Danielle Futselaar & Franck Marchis, SETI Institute

The behind-the-scenes story of this project sheds light on the complexities and challenges of designing and building a truly game-changing instrument. We started work more than thirteen years ago under the leadership of Bruce Macintosh and the auspices of the Center for Adaptive Optics. At that time, a number of scientists, most from California and Canada, met to discuss building a groundbreaking adaptive optics (AO) system powerful enough to confront — and overcome — the challenging of directly collecting photons from young Jupiter-like exoplanets. The discovery of 51 Eri b, which was announced last August, is the culmination of that effort. 

What do we know about planet formation?

Understanding how planets form in the Universe is one of the main motivations for GPI. Thanks to its advanced design, GPI specializes in finding and studying giant planets that are similar to Jupiter in our solar system. These are the kind of planets whose origin we hope to understand much better after our survey is complete.

Fig1
This artist’s impression shows the formation of a gas giant planet around a young star. Credit: ESO/L. Calçada

Hot Jupiter-esque Discovery Hints at Planet Formation

Keck Observatory press release  published on August 13 2015

MAUNAKEA, Hawaii – A team of astronomers discovered a Jupiter-like planet within a young system that could serve as a decoder ring for understanding how planets formed around our sun. The W. M. Keck Observatory on Maunakea, Hawaii confirmed the discovery. The findings were headed by Bruce Macintosh, a professor of physics at Stanford University,  and show the new planet, 51 Eridani b, is one million times fainter than its parent star and shows the strongest methane signature ever detected on an alien planet, which should yield additional clues as to how the planet formed. The results are published in the current issue of Science.

CREDIT: W. M. KECK OBSERVATORY, CHRISTIAN MAROIS, NRC CANADA Image of 51 Eri b as seen by the NIRC2 instrument on Keck Observatory's Keck II telescope. The bright central star has been mostly removed by a mask to enable the confirmation of the exoplanet one million times fainter.
CREDIT: W. M. KECK OBSERVATORY, CHRISTIAN MAROIS, NRC CANADA
Image of 51 Eri b as seen by the NIRC2 instrument on Keck Observatory’s Keck II telescope. The bright central star has been mostly removed by a mask to enable the confirmation of the exoplanet one million times fainter.

GPI Technology: Gemini Planet Imager Adaptive Optics uses Boston Micromachines MEMS deformable mirror

Adapted from Boston Micromachines Corporation press release CAMBRIDGE, MA–(Marketwired – Feb 3, 2014) –

Boston Micromachines Corporation (BMC), a leading provider of MEMS-based deformable mirror (DM) products, adaptive optics (AO) systems and scientific instruments, announced on Feb. 3 2014 that its 4K-DM is currently installed and is being used in the Gemini Planet Imager (GPI). Deployed on one of the world’s largest telescopes, the 8-meter Gemini South telescope located in the Chilean Andes, GPI is a scientific instrument which detects light from extrasolar planets.

4k-dm (1)
The Boston 4K-DM made of a continuous surface, with 4092 actuators and a stroke of 3.5 μm. (Boston Micromachine)

The Next Step in Exoplanetary Science: Imaging New Worlds

In 2003, I was lucky enough to be part of a small group of astronomers that met at the University of California at Berkeley to brainstorm on an innovative idea: the design of an instrument to image and characterize planets around other stars, called exoplanets, using a telescope in the 8 – 10 meter class. A decade later, such an instrument became reality with the arrival of the Gemini Planet Imager (called also GPI, or “Gee-pie”) instrument at the Gemini South telescope in Chile.

Five known planetary systems imaged with current adaptive optics systems. Fomalhaut shown on the top-right is the only system detected with the Hubble Space Telescope. HR8799 discovery was announced in a Science article in 2008 by a team led by C. Marois including members of the GPI team (credit: C. Marois).
Five known planetary systems imaged with current adaptive optics systems. Fomalhaut shown on the top-right is the only system detected with the Hubble Space Telescope. HR8799 discovery was announced in a Science article in 2008 by a team led by C. Marois including members of the GPI team (credit: C. Marois).