Astronomers use different telescopes to look at different kinds of light to figure out how the universe works. The only information we get about the universe tends to be light from its source. ‘Visible light’ is just an electromagnetic waves which can be seen by the human eye, it does not show us the entire universe. A type of energy that travels through the universe in the form of waves is called electromagnetic radiation. There are many other types of electromagnetic radiation also coming from the universe. The entire range of it, from high-energy gamma rays to low-energy radio waves, is called the electromagnetic spectrum. When you think about fundamental measurements in astronomy, there are different flavors of light and the parameter which governs that flavor is what we call wavelength. Visible light and all the signals that we are measuring; the gamma ray, x-ray, ultraviolet rays, infrared radiation and radio waves are electromagnetic radiation of various wavelengths. Beginning in the 1960s, a number of countries launched satellites to explore cosmic phenomena in the gamma-ray, X-ray, ultraviolet, visible, and infrared regions. More recently, space-based radio astronomy has been pursued. In the last decades of the 20th century, the United States embarked on the development of a series of long-duration orbital facilities collectively called the Great Observatories. They include the Hubble Space Telescope, launched in 1990 for observations in the visible and ultraviolet regions; the Compton Gamma Ray Observatory, launched in 1991; the Chandra X-Ray Observatory, launched in 1999; and the Spitzer Space Telescope, launched in2003. Europe and Japan have also been active in space-based astronomy and astrophysics. Europe’s Herschel infrared observatory, launched in 2009, studied the origin and evolution of stars and galaxies. A telescope aboard Japan’s Akari spacecraft, launched in 2006, also observed the universe in the infrared spectrum. NASA's great observatories which includes Hubble, Spitzer and the Compton gamma-ray observatory together with all the other telescopes and observatories around the world; there is fantastic set of data to be able to look into and work with as the multi-wavelength universe is just a really important thing in astronomy with being able to collect data for many different kinds of light. James Webb is an infrared-based telescope and again as different parts of the spectrum are tuned differently, each variety of telescopes has their targets of interests, their objects of affection in the universe are different. For example the X-ray image of the supernova remnant Crab Nebula in above collage, Chandra showed a never-before-seen ring around the central pulsar and jets that had only been partially seen by earlier telescopes. X-ray data is part of other data that combined to study and make a multi-wavelength astronomy composite imagery. And so X-rays for exoplanets are supplementing to other data, as the pieces in the puzzle helping in solving the bigger puzzle; like crawling from ant view to the complete view. Chandra of course is on the higher energy scale with X-rays but there are many different kinds of light from the radio waves, the infrared, optical that we're more used to, ultraviolet and gamma rays.
Humanity has always been drawn to the night sky. We draw pictures in the stars, track the planets, and see signs and portents in celestial objects. And so much of the universe is beyond our reach. When we look up at the night sky, there are only about 6000 stars visible to the naked human eye including few nebulae in the total sky that is below and above us as Earth itself gets in the way and can only see about a half of those from where we stand. Many objects reveal different aspects of their composition and behavior at different wavelengths. Objects are completely invisible at one wavelength, yet are clearly visible at another. Although the visible light images are spectacular, the IR image provides detail that visible light cannot. Radio waves and Infrared (IR) can penetrate the cosmic dust that makes up the nebulae clouds. Multi-wavelength astronomy fetch us complete picture of the universe as observing it in different wavelengths; radio, microwave, infrared, optical, ultraviolet, x-rays and gamma rays. As astronomy is such a multi-wavelength field, all of these different kinds of light and then even things that are not kinds of light are different tools in the astronomer’s toolkit which are needed to study various aspects of the largest structures in the universe; a multi-wavelength imagery happens to be quite obvious these days. So all of these different lights offer a different kind of tool kits for astronomer to be able to work with and when you bring them all together, you get the full picture.
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