AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Hawaii observatory3/18/2023 In recent years, advances in optical and computing technology have made it possible to greatly reduce this blurring through the use of “adaptive optics” (AO). This is true of even the world’s best observatory sites like Mauna Kea, though to a considerably lesser extent than elsewhere. This twice-per-second adjustment effectively counters the tug of gravity.Įver since their invention nearly 400 years ago, Earth-based telescopes have suffered from image blurring caused by the turbulent atmosphere above them. During observing, a computer-controlled system of sensors and actuators adjusts the position of each segment – relative to its neighbors – to an accuracy of four nanometers, about the size of a few molecules, or about 1/25,000 the diameter of a human hair. On the telescope, each segment’s figure is kept stable by a system of extremely rigid support structures and adjustable warping harnesses. Each segment’s surface is so smooth that if it were the width of Earth, imperfections would be only three feet high. Without active, computer-controlled correction of the primary mirror, scientific observations would be impossible.įor the Keck telescopes, new techniques for manufacturing, polishing and testing their mirror segments had to be invented, including “stressed mirror” polishing. This constant but subtle movement results in slight deformations of the telescope structure despite all engineered precautions. MirrorĪ telescope tracks objects, sometimes for hours, across the sky as the Earth turns. Keck Observatory was the first facility on Mauna Kea to use remote observing. Assistants operate the telescopes at the summit while astronomers gather data via remote observing from observatory headquarters in Waimea. Time allocation committees pre-approve all observing. Giant air conditioners run constantly during the day, keeping the dome temperature at or below freezing.Īstronomers use the telescopes in shifts of one to five nights. This is a big task: The volume of each dome is more than 700,000 cubic feet. A large telescope must remain resistant to the deforming forces of gravity as it tracks objects moving across the night sky.Ĭhilling the interior of the insulated dome during the day controls temperature variations that could induce deformation of the telescope’s steel and mirrors. This is critically important, and not only for economic reasons. Extensive computer analysis determined the greatest strength and stiffness for the least amount of steel- about 270 tons per telescope. “ A great observatory like the Keck is one of those human achievements which, like the Large Hadron Collider, the Human Genome Project, William Shakespeare and Franz Schubert – render me tearful with pride at belonging to the species Homo sapiens.”Īn altitude-azimuth design gives each 10-meter Keck telescope the optimal balance of mass and strength.
0 Comments
Read More
Leave a Reply. |