An innovation as crucial as the
invention of the telescope swept astronomy in the late 20th century. New technology
enabled astronomers to tune in to all the radiation coming from objects in space - and not
simply light. Capturing light tells only part of the story. It is like hearing a single
note from a melody: to experience the music fully you need to listen to all the notes from
the highest to the lowest. Light forms just one part of a whole range of electromagnetic
radiation. Tuning in to invisible waves of energy, such as radio waves and X-rays, reveals
a startlingly different picture of the universe.
Stars, galaxies, and other objects in
space all give off electromagnetic radiation. Whether it is in the form of light or radio
waves, it consists of a stream of vibrating electric and magnetic fields spreading
outward. Moving at 300,000 km/s (the speed of light), this radiation may travel thousands
or even millions of light-years toward us, but most is then absorbed by Earth's
atmosphere. Invisible astronomy has only come of age since scientists have been able to
intercept radiation in space.
Astronomical discoveries are
continuing to come about, so come check out all the forms of astronomy and see how and
what they contribute... |