When read to the astronomers, the substance of their research? We live in the age of great discoveries. But soon, most of the basic phenomena in space are known. We only know five types of cosmic ambassadors that tell us about the nature of the universe: - The electromagnetic radiation (long-wave radio radiation to gamma radiation of the highest energies), to which also the visible light belongs. It is our most important source of information. - Solid: meteorites and interplanetary dust. - Particles of cosmic radiation: electrons, protons, atomic nuclei, ions, mesons, antiparticles. - neutrinos and antineutrinos: elementary particles that have so far only been detected by the sun and the supernova 1987A. - Gravitational waves: They have not been measured directly, but have been indirectly developed by double neutron stars.

There are only about 130 multimodal phenomena in the cosmos, according to Martin Harwit, astronomy professor at Cornell University in the US. These are phenomena that can be observed in several windows. The number of unimodal phenomena, such as meteorites, is more difficult to estimate, but should be no more than a few hundred. Based on the 40 well-known phenomena we still have some surprises ahead. However, extrapolating from the previous detection rate and comparing it to the rate of rediscoveries reveals that we are not only living in the age of great astronomical insights, but that this epoch is soon over.

"If the curve correctly describes future developments, we would have to find about 90 percent of all multimodal phenomena by 2200, " says Harwit. "After that, it could take several millennia before the few remaining percentages are found. Just as the astronomical discovery story began several thousand years ago with the recognition of planets moving regularly across the starry sky, so the search can continue for thousands of years. This is especially true when many cosmic phenomena are unimodal. "

An end to astronomy is not in sight, as long as people are willing to invest time and money. On the other hand, certain astronomical phenomena may remain hidden forever because their effects do not penetrate the Earth: many elementary particles decompose too rapidly, high energy radiation and particles are slowed by the cosmic background radiation that fills the entire space, and extremely long-wave rays become interstellar Gas absorbed. display

"No wonder of technology, no ingenuity of man could help us to discover physical objects whose radiation never reaches the earth, " says Harwit. "Technology can only help the astronomer to reach the natural limits that the universe itself sets."

=== Rüdiger Vaas

© science.de

Recommended Editor'S Choice