George Mason University will be the home of the $19.5 million recently approved Landolt NASA Space Mission that will put an artificial "star" in orbit around the Earth. This 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 supernova in far-off galaxies. By establishing absolute flux calibration, the mission will begin to address several open challenges in astrophysics including the speed and acceleration of the universe expansion.
Scientists know the universe is expanding, which is measured by calculating the brightness of numerous stars and by the number of photons-per-second they emit. But more accurate measurements are needed for the next breakthroughs.
Named for late astronomer Arlo Landolt, who put together widely used catalogs of stellar brightness throughout the 1970s through the 1990s, this mission will launch a light into the sky in 2029 with a known emission rate of photons, and the team will observe it next to real stars to make new stellar brightness catalogs. The satellite (artificial star) will have eight lasers shining at ground optical telescopes in order to calibrate them for observations. The effort will not make the artificial stars so brightly to see with the naked eye, but one can see it with a personal telescope at home.
The artificial star will orbit earth 22,236 miles up, far enough away to look like a star to telescopes back on Earth. This orbit also allows it to move at the same speed of the Earth's rotation, keeping it in place over the United States during its first year in space. The payload, which is the size of the proverbial bread box, will be built in partnership with the National Institute of Standards and Technology (NIST), a world leader in measuring photon emissions.
George Mason faculty and students from Mason's College of Science and College of Engineering and Computing will work together with the NASA and NIST and nine other organizations for a first-of-its-kind project for a university in the Washington, D.C., area.
With mission control based at George Mason on its Fairfax Campus, the team also includes Blue Canyon Technologies; California Institute of Technology; Lawrence Berkeley National Laboratory; Mississippi State University; Montreal Planetarium and iREx/University of Montreal; the University of Florida; the University of Hawaiʻi; the University of Minnesota, Duluth; and the University of Victoria.
With more accurate measurements, experts will use the improved data from the project to enhance understanding of stellar evolution, habitable zones or exoplanets in proximity to Earth, and refine dark energy parameters, setting a foundation for future scientific discovery.
Learn more at landolt.gmu.edu.