- NASA has approved the $19.5 million Landolt space mission to send an artificial star into Earth orbit.
- It will be the first astronomical instrument of its kind and could revolutionize the way we study the universe.
- Among other things, the mission could help with the study of exoplanets and the expansion of space.
Astronomers usually deal with the very, very big—big telescopes, giant galaxies, and massive exploding stars.
But one of the more revolutionary astronomical tools of the decade is a breadbox-sized mini satellite. The satellite will act as an artificial star for astronomers to observe from the ground, allowing them to more accurately measure the brightness of a space object and better understand some of the biggest mysteries in our universe, such as dark energy.
NASA recently approved the $19.5 million Landolt space mission to launch a mini-satellite into Earth orbit.
“This is really amazing science that NASA is supporting,” Tyler Richey-Yowell, a postdoctoral researcher at Lowell Observatory who studies stellar astronomy and exoplanets, told Business Insider. “It’s something that will help all astronomers.”
A revolutionary new tool for astronomers
The mini-satellite, called a CubeSat, is designed to orbit the Earth from a distance of 22,236 miles. At that distance, its speed will match the Earth’s rotation, making the satellite appear fixed in the night sky and an easy target for telescopes to track.
You can’t see it with the naked eye. But to telescopes it will look like a star. The launch of the mission is planned for 2029. It will be the first instrument of its kind.
“It’s really new for us to have an artificial star up there that we can rely on and use,” Richey-Yowell told BI.
What makes this “artificial star” better than the real thing is that astronomers will know exactly how much light it emits.
The CubeSat, named Landolt for the late astronomer Arlo Landolt, will fire lasers with a specific number of light particles, or photons, that astronomers can use to calibrate their telescopes to measure light.
This can help eliminate a lot of the guesswork that astronomers now do when using real stars to calibrate their instruments.
The problem is that there’s no way to know exactly how much light a real star emits because we can’t send a probe to one to accurately measure its brightness, Richey-Yowell said. In addition, Earth’s atmosphere absorbs a lot of light from space, which can also affect astronomers’ calibrations.
“That’s why this Landolt mission is so important,” Richey-Yowell said, adding that “if we send a mission like this where we know exactly how many photons and how much light per second is coming from this CubeSat,” then it could be used to compare and more accurate measurements of light from other objects, such as real stars.
Live Science reported that the mission should help astronomers measure the light emitted by stars with ten times the precision of current estimates.
It’s like being given a 1,000 piece puzzle with only half the pieces and then someone giving you a few hundred extra pieces. Landolt can help astronomers pick up tiny details that they would otherwise miss in the data.
How Landolt could revolutionize astronomy
“All of our astronomy is based on light, so we really need to know how much light we’re actually receiving,” Richey-Yowell said.
You can learn a lot from a beam of light: a star’s temperature, its mass, the types of exoplanets orbiting it, and whether they might harbor life.
For example, knowing how hot the host star is can tell you how far away an exoplanet needs to be to hold liquid water on its surface, Richey-Yowell said. Water is a major component of life as we know it, and a key feature that astrobiologists look for when searching for potential planets that could host life.
Finding other Earth-like planets is just the beginning. Astronomers can also use Landolt to measure light from distant exploding stars, called supernovae, which can help calculate the rate at which the universe is expanding.
Right now, cosmologists studying the expansion of the universe face a huge challenge: they can’t settle for a single value for the expansion rate. Some methods lead to one value, while others lead to a slightly different one. This puzzle could be the key to unlocking some of the universe’s greatest mysteries, such as understanding the invisible force tearing our universe apart that we call dark energy.
“So really anything from tiny, tiny planets to the entire universe depends on our understanding of stars and how bright they are and what kind of light they emit,” Richey-Yowell said. “I really think it’s going to be revolutionary for astronomy.”