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Virtual Star Helps Mitigate Atmospheric Distortion
tanveer1979 writes: "Space.com is running a story about a new star in the sky created by humans to study astronomy better. To improve the usefulness of the Keck II telescope atop Mauna Kea in Hawaii, engineers created a virtual star to aid in a complex process that adjusts for the turbulence in Earth's atmosphere in order to create better images of distant objects."
The ISS is rarely over a particular spot on the Earth. In addition, we want to know the atmospheric properties in the direction of what we're observing. Not only does the ISS make passes every few hours for 2-3 minutes of visible time on the horizon for a particular location, but you'd be limited to observing objects nearly adjacent to the ISS. And because it moves so quickly, the long exposures that deep sky objections need would be impossible.
This technology is attached to the telescope, so it's pointed at the sky with a constant offset from the current point of observation, and it's then monitored with a much smaller (6 inch, instead of 33 feet for a Keck mirror) telescope with adaptive optics, the corrections for which will eventually be mimicked on the full scale mirror, once they get it fully functioning (it's not yet, but they can make the corrections on the 6" scope now).
You're free to shoot lasers at the space station if you want, though.