PureInsight | March 17, 2003
[PureInsight.org] The National Science Foundation funded the telescope called AMANDA. It's 400 meters wide and has 308 bowling ball size light sensors. It's not in an observatory, but buried deep under Antarctica. Although its eyes are "blindfolded" since it is in dark, its vision is unmatched. AMANDA can "see" colliding black holes, gamma-ray bursts, the cores of far away galaxies, and the debris of exploded stars. It can see things humans didn't imagine possible. How could this be? It is all because of neutrinos.
Neutrinos that Hide Themselves
Neutrinos have high energy readings, and they are scattered all over the universe. How many neutrinos are there? Every proton corresponds to 1,000,000,000 neutrinos. But we can't see neutrinos, and they are difficult to detect. Neutrinos are extremely small; they don't carry any charge and have very little mass. They can penetrate anything without difficulty, from planets, to stardust, to electromagnetic fields. "There are billions of neutrinos penetrating our bodies in any given second," said Francis Halzen of the University of Wisconsin-Madison. "But we can't feel any of them."
Amanda Sees Better When Blindfolded
Because of the nature of neutrinos, they can penetrate the earth. AMANDA takes advantage of this. It has been hidden 1.5 kilometers underground and is facing the earth instead of sky. Although it's located at the South Pole, its "eyes" can penetrate the earth and see the North Pole. When the earth has filtered out light and radiation, AMANDA then "sees" the world made up of neutrinos.
AMANDA's current mission is to observe high-energy neutrinos. High-energy neutrinos have 10,000 times more energy than that of the low-energy neutrinos emitted by the sun. Physicists hope to use it to explore the unknown universe. AMANDA can measure neutrino's directions within 3.5 degrees. This is accurate enough to reveal the source of the neutrinos. Whenever gamma-rays burst, black holes collide, etc., they emit neutrinos.
An international collaboration made up of physicists and astronomers revealed their progress on February 1, 2003. Steve Barwick, of the University of California-Irvine, Department of Physics and Astronomy, AMANDA's co-spokesperson, said, "Now, we have a new and powerful tool to explore the universe." Aizenman, of the National Science Foundation, felt that AMANDA, in addition to providing more information on known phenomenon, could discover types of matter and events that we could never have imagined possible.
An atom is small, but we can see materials made up of billions of atoms. But we still can neither see nor touch materials made up of billions of neutrinos. What is a world made up of neutrinos like? Hopefully, AMANDA will be able to provide at least some information, however small.
Reference:
Website of the University of California, Irvine, http://www.ps.uci.edu/~amanda/
Additional source: http://today.uci.edu/news/release_detail.asp?key=970
Translated from: http://zhengjian.org/zj/articles/2003/2/7/20343.html
