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Yale Astronomy

Time to observe!

Mar 13, 2019 - Debra Fischer

The data have been rolling in and the quality of the spectra is exceptional. We are writing up a few papers on technical results, highlighting our 10 cm/s instrumental precision, but are also beginning to do science! We have a few favorite stars that we observe frequently to demonstrate our precision on various timescales. We are also beginning the 100 Earth's project in earnest, aiming to detect small rocky planets at habitable zone distances. And we are finding that the very high fidelity of EXPRES spectra makes it possible to look at atomic features in exoplanet atmospheres.

For our slide show this month, we are leading with an image showing [1] the EXPRES instrumental precision. This image was obtained by cross-correlating laser comb observations taken over a couple of days. Each set of data (color coded) is shifted to the same zero point showing 1-sigma scatter of 7 centimeters per second! [2] One of the terrific undergrads in my "Frontiers and Controversies in Astrophysics" class accompanied me for the start of this run. Rebecca operated the telescope for our observations on Saturday, Mar 9th. After a couple of days, [3] grad students Sam Cabot and Joel Ong arrived at the DCT to finish up observing for the week. [4] The big challenge this trip has been snow and wind. We wait for a break in the weather and then spring into action when it is safe to open the dome. [5] The weather is intensely beautiful, but stressful because it blocks our ability to collect data. [6] Finally, the weather begins to clear. The view over the valley from the ridge of the DCT is gorgeous; the plants are encased in ice, the sky is blue, and clouds are breaking. [7] Joel walks around the DCT telescope, surveying ice falling off the dome. [8] Joel, Sam and Debra go out on the catwalk to watch the sunset.

March 12, 2019 Slideshow

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EXPRES instrumental precision: 7 cm/s
Rebecca operating the telescope
Grad students Sam and Joel arrive at the DCT Lodge.
March comes in like a lion
Beautiful, but not good observing!
View from the DCT ridge as the weather begins to break.
Joel walking around the telescope
Joel, Sam and Debra on the catwalk at sunset at DCT

About Us

Photo from Lowell Observatory

The EXPRES team works on the discovery of planets orbiting stars other than our Sun, or exoplanets.

EXPRES is a next generation spectrograph that aims to break the record on current measurement precision with the goal of detecting small, rocky planets - similar to Earth - orbiting nearby stars. The instrument blends high resolution and extraordinary stability to produce the highest fidelity data.

This journey began long ago; our hope is that EXPRES will help humanity to explore the unknowns in the galaxy.

EXPRES is possible thanks to...

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2018: December, September, July, June, May, April, March.

EXPRES Cast and Crew

  • Professors
    • Debra Fischer, Astronomy
    • Jessi Cisewski, Statistics
  • Research Scientists
    • Colby Jurgenson
    • Tyler McCracken
    • David Sawyer
    • Andrew Szymkowiak
  • Postdoctoral Associates and Fellows
    • John Michael Brewer
  • Graduate Students
    • Allen Davis
    • Ryan Blackman
    • Ryan Petersburg
    • Lily Zhao
    • Joel Ong
  • Undergraduate Students
    • Christopher Leet
    • Yonatan Zeff
    • Abby Mintz
  • Collaborators
    • Sally Dodson-Robinson, University of Delaware
    • Lars Buchhave, Danish National Space Institute
    • Gregory Henry, Tennessee State University
  • We Would Like to Expressly Thank
    • Steve Girvin, Yale University
    • Pieter van Dokkum, Yale University
    • Gábor Fűrész, MIT
    • Andy Szentgyorgyi, Harvard
    • Francesco Pepe, Geneva Observatory
    • Matteo Genoni, Brera Astronomical Observatory
    • Giorgio Pariani, Brera Astronomical Observatory
    • Marco Riva, Brera Astronomical Observatory
    • Ben Hardesty, Lowell Observatory
    • Frank Cornelius, Lowell Observatory