NASA plans to launch "artificial star" into Earth orbit

NASA recently approved the $19.5 million Landolt Space mission to launch this mini-satellite, an artificial star, into Earth orbit. Astronomers will be able to observe the satellite from the ground, helping them measure the brightness of an object in space more accurately and better understand some of the biggest mysteries of our universe, such as dark energy. Dark energy is causing the universe to expand at an ever-increasing rate, and about 68.3 to 70 percent of the universe is dark energy.

The mini-satellite, called a CubeSat, is designed to orbit Earth at a distance of 35,785 kilometers (22,000 miles). At that distance, the CubeSat's speed will match Earth's rotation, so it will appear stationary in the night sky. Telescopes will also be able to easily track the CubeSat.

The CubeSat won't be visible to the naked eye. But to a telescope, it will look like a star. The CubeSat is scheduled to launch in 2029.

What makes this “artificial star” better than a real one is that astronomers will know exactly how much light it emits. The CubeSat will fire a laser with a specific number of photons. Photons are quanta of light. That way, astronomers can calibrate their telescopes to measure the light.

This takes a lot of the guesswork out of using stars to calibrate their instruments. The problem is that there is no way to know exactly how much light the stars emit. Furthermore, Earth’s atmosphere absorbs a lot of light from space, which can also affect astronomers’ calibrations.

“Our entire astronomy is based on light, so it’s important to know how much light we’re actually getting,” says Tyler Richey-Yowell, a researcher at the Lowell Observatory in the US. A single flash of light can tell us a lot about a star, such as its temperature, its mass, the planets it orbits, and whether they could harbor life.