The light from objects in the distant Universe is stretched by a phenomenon called redshift. This means that a given wavelength is sensitive to different objects in the nearby and distant Universe. Type Wavelength Our Galaxy and nearby galaxies Distant Universe Sub-mm 300–1000 of stars Birth of stars m Very cold dust Cool dust Far-IR 30–300 Cool dust Birth of stars m Birth of stars Warm dust around young stars Outermost regions of the solar system (Uranus, Neptune, Kuiper Belt, comets) Mid-IR 3–30 Warm dust around stars The first stars (100 million years after m Big Bang) Formation of planets Solar System (Mars, Jupiter, Saturn, Asteroids) Near-IR 0.8 3 Cool stars (red dwarfs, red giants) The first galaxies in the Universe (400 m – million years after the Big Bang) Near-Earth objects Optical 0.4–0.8 Most Hot, young stars m Nearby galaxies UV 0.1–0.4 Hot, young stars Very hot regions m Your choices Some instruments need to operate at low temperatures. In general, the instrument must be cooler than the objects it is looking at. The temperature requirements of the different instruments are given below. Instrument wavelength Temperature requirement Sub-mm 0.4 K Far-infrared 0.4 K Mid-infrared 40 K Near-infrared 4 K 300 K Optical Ultraviolet 400 K
The light from objects in the distant Universe is stretched by a phenomenon called redshift. This means that a given wavelength is sensitive to different objects in the nearby and distant Universe. Type Wavelength Our Galaxy and nearby galaxies Distant Universe Sub-mm 300–1000 m of stars Very cold dust Birth of stars Cool dust Far-IR 30–300 m Cool dust Birth of stars Outermost regions of the solar system (Uranus, Neptune, Kuiper Belt, comets) Birth of stars Warm dust around young stars Mid-IR 3–30 m Warm dust around stars Formation of planets Solar System (Mars, Jupiter, Saturn, Asteroids) The first stars (100 million years after Big Bang) Near-IR 0.8 – 3 m Cool stars (red dwarfs, red giants) Near-Earth objects The first galaxies in the Universe (400 million years after the Big Bang) Optical 0.4–0.8 m Most Nearby galaxies Hot, young stars UV 0.1–0.4 m Hot, young stars Very hot regions Your choices Some instruments need to operate at low temperatures. In general, the instrument must be cooler than the objects it is looking at. The temperature requirements of the different instruments are given below. Instrument wavelength Temperature requirement Sub-mm 0.4 K Far-infrared 0.4 K Mid-infrared 40 K Near-infrared 4 K Optical 300 K Ultraviolet 400 K
SpaceTelescopeDesigner_StudentGuide_KS4.docx