Fundamental questions in astrophysics and remote sensing rely on accurate radiometry. NIST is at the forefront of developing methods to improve relative and absolute spectroradiometric calibration of ground- and space-based telescopes, and of the celestial bodies they view.. We use specialized  facilities at NIST, including SIRCUS, the Facility for Spectral Irradiance and Radiance responsivity Calibrations using Uniform Sources; and LBIR, the Low Background Infrared Facility for the calibration and characterization of of instrumentation. Opportunities are available in instrument development and automation, astronomical and atmospheric data analysis. Participation in more than one project is possible.

Our Current Projects:

NIST Stars: Motivated by the needs of dark energy investigations and exoplanet research, we are building an astronomical calibration station on Cerro Paranal in Chile in collaboration with the European Southern Observatory. Our goal is to measure to high accuracy the SI-traceable spectral energy distribution over the visible and near infrared wavelength range for a set of stars for use as flux standards for astronomy. In addition to stellar spectroscopy, we carry out measurements to improve the determination of atmospheric corrections. Instrumentation includes visible and infrared telescopes and spectrographs, a water vapor radiometer, and micro-pulse LIDAR.

CANDLE (Calibration using an Artificial Star with NIST-traceable Distribution of Luminous Energy) is a NASA-funded project to design, build, and test a precision SI-traceable, artificial star engineering demonstration unit (EDU) that provides calibrated light between 300 nm and 2000 nm  using three different modes, matching the wavelength range of surveys for dark energy studies with Roman Space Telescope and Rubin Observatory. By calibrating the output beam profiles, rigorously demonstrating the uncertainty budget, and establishing performance parameters for different orbits, we aim to establish the path toward a flight-ready payload.

LS4 CBP: Collimated Beam Project system for the 1-m Schmidt telescope at La Silla, Chile.  This NASA funded project will design, build and deploy a calibrated light source at the La Silla Observatory to routinely measure the total system throughput of the Schmidt Telescope in support of the La Silla Schmidt Southern Survey (LS4).  LS4 aims to provide an anchor for the Roman Space Telescope's High Latitude Survey for a Type Ia supernova survey.

Landolt: A new NASA funded Pioneers project to place a small payload  in orbit that will provide laser light at several wavelengths in the visible and infrared to help calibrate ground-based telescopes.

Airborne Lunar Spectral Irradiance Instrument (Air-LUSI): The moon is an on-orbit absolute calibration source for weather and climate satellites in the visible and near infrared range. Air-LUSI makes the most accurate measurements of lunar spectra from above 95% of the Earth's atmosphere. This project uses NASA's ER-2 aircraft, which fly at an altitude of 21 km above sea level. These data will serve as tie points for new and existing models of the lunar spectral irradiance.

Mauna Loa Observatory Lunar Spectral Irradiance Instrument (MLO-LUSI): Complementary to Air-LUSI, but located at the NOAA observatory on Mauna Loa, Hawai'i at 3400 m above sea level, will take observations over several years once vehicle access is restored to the observatory. The goal is to provide a good sample of Sun-Moon-Earth angles to allow creation of an SI-traceable model of the lunar spectral irradiance. Collaboration with atmospheric scientists to improve nighttime measurements of aerosols and trace gases is an important component of the project.

Links:
Air-LUSI -- https://www.nist.gov/measuring-cosmos/airborne-lunar-spectral-irradiance-air-lusi-instrument
MLO-LUSI -- https://www.nist.gov/measuring-cosmos/mlo-lunar-spectral-irradiance-mlo-lusi-project
NIST Stars https://www.nist.gov/programs-projects/nist-stars

key words

Astrophysics; Radiometry; Optics; Infrared astronomy; Satellite calibration; Atmospheric transmittance; Calibration; Spectral Energy Distribution; Dark energy; Remote Sensing;

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral applicants