National Aeronautics and Space Administrion

Since its inception in 1958, NASA has accomplished many great scientific and technological feats in air and space. NASA technology also has been adapted for many nonaerospace uses by the private sector. NASA remains a leading force in scientific research and in stimulating public interest in aerospace exploration, as well as science and technology in general. Perhaps more importantly, our exploration of space has taught us to view Earth, ourselves, and the universe in a new way. While the tremendous technical and scientific accomplishments of NASA demonstrate vividly that humans can achieve previously inconceivable feats, we also are humbled by the realization that Earth is just a tiny "blue marble" in the cosmos. Check out our "Thinking About NASA History" folder online as an introduction to how history can help you.

Friday, September 15, 2023

Quasar

Did you know?

"If quasars were common beyond redshift 7.5, then astronomers would have found several more by now. But their spatial density --the numbers of quasars in a given volume of space--appears to be very low, only about one quasar per cubic gigaparsec, where a gigaparsec is 3.26 billion light years. "You have to survey huge areas of the sky to find these objects just because they are intrinsically so rare in the universe."

Astronomy Magazine April  2022 "How to Grow a Giant Black Hole" pp. 18-19
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