A Mississippi State University astrophysicist will lead a $19.5 million NASA space mission to put an artificial star in orbit around the Earth.
Angelle Tanner, an associate professor in the Department of Physics and Astronomy at Mississippi State, is serving as the principal investigator on the Landolt mission, part of the NASA Astrophysics Pioneers program. The program’s artificial star will allow scientists to calibrate telescopes and more accurately measure the brightness of stars ranging from those nearby to the distant explosions of supernovas in far-off galaxies.
By establishing absolute flux calibration, the mission will address several open challenges in astrophysics including the speed and acceleration of the universe expansion.
Tanner is managing a sub-grant of $300,000 for the project. Her work on the mission relies on cubesats, which are small satellites orbiting Earth. Each cubesat contains four lasers specially calibrated by the National Institute of Standards and Technology, an agency of the U.S. Department of Commerce.
“The program includes a cubesat and a set of ‘ground stations,’ which are telescopes. As the cubesat flies over a location, the ground stations will observe the cubesat in the same frame as their science target,” Tanner said.
“The point is to use the image of the laser to determine the amount of starlight being absorbed by the Earth’s atmosphere. This will reduce the uncertainties in the value of the brightness of the star from 10 percent to one percent. That makes a difference when propagated into the properties of exoplanets and, believe it or not, some of the parameters used to determine the structure of the universe.”
Working with the team at George Mason University in Virginia, the mission is named in honor of LSU Professor Arlo Landolt, who Tanner calls the “the father of photometry.” To follow the mission’s progress, click here.
