NASA Approves Mission to Launch “Artificial Star” for astronomers - "Landolt"
Quote:
Originally Posted by CHARLES Q. CHOI, IEEE
NASA has new plans to launch a tiny satellite mimicking a star into space. The goal of the laser-carrying, bread-box-size orbiter is to calibrate telescopes by using the satellite as a pseudostar with precisely known features. The resulting boost in accuracy for these observatories may one day help reveal new details about exoplanets around distant stars, as well as the mysterious “dark energy“ that is accelerating the expansion of the universe.
The newly approved US $19.5 million Landolt mission, scheduled to begin in 2028 or 2029, will launch a satellite about the size of a 12U CubeSat (about 20 by 20 by 34 centimeters). The plan is for the satellite to orbit Earth roughly 35,800 kilometers above the equator, which is far enough away to look like a star to telescopes on the ground. The orbit will also be a geostationary one that will keep the satellite off the southwest coast of the United States, where telescopes in California, Chile, and Hawaii can see it.
....
The lasers will range in power from 0.1 to 0.5 watts. The artificial star will not be bright enough to be seen with the naked eye on Earth but will be visible with a personal telescope at home. “Everyone hears that we’re launching space lasers, and everyone gets excited, ‘pew pew,’ ” Plavchan says. “But these will be more than 100 times dimmer than the faintest thing the eye can see in the darkest locations.”
The satellite will use fiber lasers, “which are very stable sources of light,” Plavchan says. The aim for the Landolt mission is to emit photons at known reliable rates, which telescopes can use as baselines for their estimates of the brightness of anything else in the sky.
Currently, when it comes to how accurate modern telescopes are at measuring how bright a distant star is—how many photons from it arrive per second—“some say they are accurate within 1 percent, some 2 or 3 or worse,” Plavchan says. “This mission aims to decrease this uncertainty to less than 0.5 percent.”
And yes, pity it's not going to be mag 2 or 3 as a static star would have been awesome for collimation though probably not from Australia if it's going to be aligned with the US.
