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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 the next breakthroughs will require more accurate measurements, and that’s where George Mason is stepping in. The university is leading Landolt, a $19.5 million NASA space mission that will put an artificial “star” in orbit around Earth.

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Here’s what’s to come:

1. Led by astronomy professor Peter Plavchan, faculty members and students from the College of Science and the College of Engineering and Computing will work together with staff from NASA, the National Institute of Standards and Technology (NIST), and nine other organizations on a first-of-its-kind project for a university in the Washington, D.C., area.
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2. The artificial star will allow scientists to calibrate telescopes and more accurately measure the brightness of a wide range of stars—from those nearby to the distant explosions of supernovae 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’s expansion.
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3. The mission is named for late astronomer Arlo Landolt, who compiled the widely used catalogs of stellar brightness through the 1990s.
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4. The payload, which is the size of a proverbial bread box, will be built in partnership with NIST, a world leader in measuring photon emissions. “This calibration under known laser wavelength and power will remove effects of atmosphere filtration of light and allow scientists to significantly improve measurements,” says electrical engineering professor Piotr Pachowicz, who is leading this component of the mission.
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5. The artificial star, expected to launch in 2029, will orbit 22,236 miles above Earth, far enough away to look like a real star to telescopes back on the ground. This orbit also allows the star to move at the same speed as the Earth’s rotation, keeping it in place over the United States during its first year in space. “This is what is considered an infrastructure mission for NASA, supporting the science in a way that we’ve known we needed to do but with a transformative change in how we do it,” says Plavchan.
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"This mission marks another first for George Mason, a milestone that proves our impact as a major public research university that truly knows no bounds,” says President Gregory Washington.

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