What is the Spitzer Space Telescope?

The Spitzer Space Telescope, a U.S. satellite and the last of NASA's "Great Observatories," studied the cosmos using infrared wavelengths . Launched in 2003 and named for Lyman Spitzer, Jr., it gathered data for over 16 years on the origins, evolution, and composition of planets, stars, galaxies, and the universe. Orbiting the Sun to escape Earth's thermal effects, the Spitzer Space Telescope had an 85-cm primary mirror that focused infrared light on its instruments. These instruments included an infrared camera, a spectrograph, and an imaging photometer, covering a 3 to 180 micrometre wavelength range. Spitzer's observations led to results regarding extrasolar planets. It determined the temperature, atmospheric structure, and composition of these planets. It also detected infrared radiation from sources nearly 13 billion years away, revealing galaxies formed soon after the big bang .

Which country built and launched the Spitzer Space Telescope?

The Spitzer Space Telescope is a U.S. satellite and the last of NASA's "Great Observatories" satellites. It was launched on August 25, 2003, using a Delta II rocket. The satellite studied the cosmos at infrared wavelengths, gathering data for over 16 years on the origins, evolution, and composition of planets, stars, galaxies, and the universe. The telescope is named after Lyman Spitzer, Jr. , an American astrophysicist who foresaw the potential of space-based astronomical telescopes in a 1946 paper.

What kind of light does the Spitzer Space Telescope use to observe space?

The Spitzer Space Telescope studied the cosmos using infrared wavelengths . It had an 85-cm primary mirror that focused infrared light on its instruments. These instruments included a spectrograph, a general-purpose near-infrared camera, and an imaging photometer. Together, the instruments covered a wavelength range of 3 to 180 micrometers.

What scientific discoveries has Spitzer made about our Solar System or other galaxies?

The Spitzer Space Telescope made significant contributions to astronomy by studying the cosmos at infrared wavelengths. One of its striking results was the study of extrasolar planets. Because central stars heat these planets, the planets produce enough infrared radiation for Spitzer to detect and determine their temperature, atmospheric structure, composition, and dynamics. Spitzer detected infrared radiation from sources so far away that it looked back almost 13 billion years to when the universe was less than 1 billion years old. It showed that some galaxies had already grown to the size of present-day galaxies and must have formed within a few hundred million years of the big bang. Spitzer also discovered Saturn’s outermost ring. This dust ring arises from impacts on the moon Phoebe. Particles from this ring spiral inward toward Saturn and have caused the asymmetry in brightness between the two hemispheres of Iapetus.

How does the Spitzer Space Telescope help astronomers learn about planets outside our Solar System?

The Spitzer Space Telescope helped astronomers study exoplanets by detecting the infrared radiation they emit, since these planets are heated by their central stars to around 1,000 K (700 °C, or 1,300 °F). This allowed Spitzer to determine the temperature, atmospheric structure, composition, and dynamics of several exoplanets. Additionally, Spitzer observed the transits of the seven Earth-sized planets in the TRAPPIST-1 system, three of which are in the star’s habitable zone, where liquid water could exist on the planet's surface.

How is the Spitzer Space Telescope different from other space telescopes, like Hubble?

The Spitzer Space Telescope differed from other "Great Observatories" like the Hubble Space Telescope in several ways. Unlike Hubble, which detects visible, ultraviolet, and infrared light, Spitzer studied the cosmos at infrared wavelengths . Also, to avoid the Earth's thermal radiation, Spitzer was placed in a heliocentric orbit that allowed it to drift away from Earth, while Hubble orbits Earth at approximately 600 km (370 miles). Spitzer's infrared detectors used large-format arrays with tens of thousands of pixels and required cryogenic cooling to reduce interference. Its solar orbit simplified cooling, maintaining the telescope at 5–15 K (-268 to -258 °C, or -450 to -432 °F).

Spitzer Space Telescope

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Cassiopeia A supernova remnant, in a false-colour composite image synthesized from observations gathered in different spectral regions by three space-based observatories. Red areas, representing infrared data from the Spitzer Space Telescope, highlight warm dust in the remnant's outer shell. Yellow areas, representing visible-light data collected by the Hubble Space Telescope, show delicate filamentary structures made of warmer gases. Green and blue areas are X-ray data from the Chandra X-ray Observatory and reveal hot gas that was created when ejected material from the supernova collided at very high velocity with the surrounding gas and dust.

Learn how the planets of Trappist-1 were discovered and about their potential for liquid water and life

Spitzer Space Telescope

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Top Questions

What is the Spitzer Space Telescope?
The Spitzer Space Telescope, a U.S. satellite and the last of NASA's "Great Observatories," studied the cosmos using infrared wavelengths. Launched in 2003 and named for Lyman Spitzer, Jr., it gathered data for over 16 years on the origins, evolution, and composition of planets, stars, galaxies, and the universe.

Orbiting the Sun to escape Earth's thermal effects, the Spitzer Space Telescope had an 85-cm primary mirror that focused infrared light on its instruments. These instruments included an infrared camera, a spectrograph, and an imaging photometer, covering a 3 to 180 micrometre wavelength range.

Spitzer's observations led to results regarding extrasolar planets. It determined the temperature, atmospheric structure, and composition of these planets. It also detected infrared radiation from sources nearly 13 billion years away, revealing galaxies formed soon after the big bang.
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1. infrared astronomy
2. Spitzer Space Telescope
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Which country built and launched the Spitzer Space Telescope?
The Spitzer Space Telescope is a U.S. satellite and the last of NASA's "Great Observatories" satellites. It was launched on August 25, 2003, using a Delta II rocket. The satellite studied the cosmos at infrared wavelengths, gathering data for over 16 years on the origins, evolution, and composition of planets, stars, galaxies, and the universe.

The telescope is named after Lyman Spitzer, Jr., an American astrophysicist who foresaw the potential of space-based astronomical telescopes in a 1946 paper.
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1. Spitzer Space Telescope
2. Lyman Spitzer
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What kind of light does the Spitzer Space Telescope use to observe space?
The Spitzer Space Telescope studied the cosmos using infrared wavelengths. It had an 85-cm primary mirror that focused infrared light on its instruments. These instruments included a spectrograph, a general-purpose near-infrared camera, and an imaging photometer. Together, the instruments covered a wavelength range of 3 to 180 micrometers.
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What scientific discoveries has Spitzer made about our Solar System or other galaxies?
The Spitzer Space Telescope made significant contributions to astronomy by studying the cosmos at infrared wavelengths. One of its striking results was the study of extrasolar planets. Because central stars heat these planets, the planets produce enough infrared radiation for Spitzer to detect and determine their temperature, atmospheric structure, composition, and dynamics.

Spitzer detected infrared radiation from sources so far away that it looked back almost 13 billion years to when the universe was less than 1 billion years old. It showed that some galaxies had already grown to the size of present-day galaxies and must have formed within a few hundred million years of the big bang.

Spitzer also discovered Saturn’s outermost ring. This dust ring arises from impacts on the moon Phoebe. Particles from this ring spiral inward toward Saturn and have caused the asymmetry in brightness between the two hemispheres of Iapetus.
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Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How does the Spitzer Space Telescope help astronomers learn about planets outside our Solar System?
The Spitzer Space Telescope helped astronomers study exoplanets by detecting the infrared radiation they emit, since these planets are heated by their central stars to around 1,000 K (700 °C, or 1,300 °F). This allowed Spitzer to determine the temperature, atmospheric structure, composition, and dynamics of several exoplanets. Additionally, Spitzer observed the transits of the seven Earth-sized planets in the TRAPPIST-1 system, three of which are in the star’s habitable zone, where liquid water could exist on the planet's surface.
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1. Spitzer Space Telescope
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How is the Spitzer Space Telescope different from other space telescopes, like Hubble?
The Spitzer Space Telescope differed from other "Great Observatories" like the Hubble Space Telescope in several ways. Unlike Hubble, which detects visible, ultraviolet, and infrared light, Spitzer studied the cosmos at infrared wavelengths. Also, to avoid the Earth's thermal radiation, Spitzer was placed in a heliocentric orbit that allowed it to drift away from Earth, while Hubble orbits Earth at approximately 600 km (370 miles).

Spitzer's infrared detectors used large-format arrays with tens of thousands of pixels and required cryogenic cooling to reduce interference. Its solar orbit simplified cooling, maintaining the telescope at 5–15 K (-268 to -258 °C, or -450 to -432 °F).
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Spitzer Space Telescope, U.S. satellite, the fourth and last of the National Aeronautics and Space Administration fleet of “Great Observatories” satellites. It studied the cosmos at infrared wavelengths. The Spitzer observatory began operating in 2003 and spent more than 16 years gathering information on the origin, evolution, and composition of planets and smaller bodies, stars, galaxies, and the universe as a whole. It was named in honour of Lyman Spitzer, Jr., an American astrophysicist who in a seminal 1946 paper foresaw the power of astronomical telescopes operating in space.

The Spitzer observatory was launched on August 25, 2003, by a Delta II rocket. To remove the spacecraft from Earth’s thermal radiation effects, it was placed into a heliocentric, or solar, orbit with a period of revolution that causes it to drift away from Earth at a rate of 0.1 astronomical unit (15 million km, or 10 million miles) per year. This orbit differed radically from the low Earth orbits used by Spitzer’s sister Great Observatories—the Hubble Space Telescope, the Compton Gamma Ray Observatory, and the Chandra X-ray Observatory.

The satellite was a little over 4 metres (13 feet) tall and weighed about 900 kg (2,000 pounds). It was built around an all-beryllium 85-cm (33-inch) primary mirror that focused infrared light on three instruments: a general-purpose near-infrared camera, a spectrograph sensitive to mid-infrared wavelengths, and an imaging photometer taking measurements in three far-infrared bands. Together the instruments covered a wavelength range of 3 to 180 micrometres. These instruments exceeded those flown in previous infrared space observatories by using as their detectors large-format arrays with tens of thousands of pixels.

View of the Andromeda Galaxy (Messier 31, M31).

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To reduce interference caused by thermal radiation from the environment and from their own components, infrared space observatories require cryogenic cooling, typically to temperatures as low as 5 K (−268 °C, or −450 °F). Spitzer’s solar orbit simplified the satellite’s cryogenic system by taking it away from the heat of Earth. Much of the satellite’s own heat was radiated into the cold vacuum of space, so that only a small amount of precious liquid helium cryogen was needed to maintain the telescope at its operating temperature of 5–15 K (−268 to −258 °C, or −450 to −432 °F).

The most striking results from Spitzer’s observations concerned extrasolar planets. Since the central stars around which those planets revolve heat the planets to some 1,000 K (700 °C, or 1,300 °F), the planets themselves produced enough infrared radiation for Spitzer to easily detect them. Spitzer determined the temperature and the atmospheric structure, composition, and dynamics of several extrasolar planets. Spitzer also observed the transits of the seven Earth-sized planets in the TRAPPIST-1 system, three of which are in the star’s habitable zone, the distance from a star where liquid water can survive on a planet’s surface.

HUDF-JD2Distant galaxy HUDF-JD2 (enclosed in circles) as seen by the Spitzer Space Telescope in the infrared (bottom right), by the Hubble Space Telescope in visible light (top right) and in the near-infrared (bottom left), and in a combination of the Hubble and Spitzer images (top left).

Spitzer also detected infrared radiation from sources so far away that in effect it looked almost 13 billion years back in time to when the universe was less than 1 billion years old. Spitzer showed that even in that early epoch some galaxies had already grown to the size of present-day galaxies and that they must have formed within a few hundred million years of the big bang that gave birth to the universe some 13.7 billion years ago. Such observations can provide stringent tests of theories of the origin and growth of structure in the evolving universe.

Because Spitzer was sensitive to infrared radiation emitted from dust, it also discovered Saturn’s outermost ring, which extends from 7.3 to 11.8 million km (4.6 to 7.4 million miles) from Saturn and is the largest planetary ring in the solar system. This dust ring arises from impacts on the moon Phoebe, and particles from this ring that spiral inward toward Saturn have caused the marked asymmetry in brightness between the two hemispheres of Iapetus.

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Astronomers continued to use all of Spitzer’s capabilities until May 15, 2009, when the liquid helium cryogen was depleted. Even without the helium, however, Spitzer’s unique thermal design and its solar orbit ensured that the telescope and instruments reached a new equilibrium at a temperature of only 30 K (−243 °C, or −405 °F). At this temperature, Spitzer’s two shortest-wavelength-detector arrays continued to operate without any loss of sensitivity. Spitzer’s 5.5-year cryogenic mission was thus followed by a “warm Spitzer” mission, which lasted until the satellite was decommissioned on January 30, 2020.

Michael Werner

Spitzer Space Telescope

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