Infrared telescope

Some tools look at space using heat.

They see things our eyes cannot see. Most things in space give off heat.

Some of these tools sit on the ground. They sit on high, dry mountains. This is because water in the air blocks the heat.

Other tools fly high in the sky. Some fly on big planes.

This helps them see better.

The best tools go into space. They do not have to look through our air. One new tool uses power from the sun. It is a very big tool for the sky.

An infrared telescope is a tool used to see space. It looks for infrared light. This is a type of light we cannot see with our eyes. Most things in space give off this kind of light. This happens because they have heat.

These telescopes can be on the ground. They can also fly in the air or sit in space. Ground telescopes are often on high, dry mountains. This is because water in the air blocks the light. Scientists once used balloons and rockets to get higher. Some big planes even carry them.

Putting a telescope in space is very helpful. It lets the tool look past the Earth's air. One big project was called IRAS. It launched in 1983. It showed us things about our galaxy, the Milky Way. Today, NASA uses the James Webb Space Telescope. It launched in late 2021. It uses power from the sun to work. This tool helps us study the stars and the deep sky.

An infrared telescope is a special tool for seeing the universe. It looks for infrared light in space. This light is part of the electromagnetic spectrum. All objects with heat give off this kind of light. Even things that are very cold emit it. Scientists use many types of telescopes to see different things. Some look at X-rays or ultraviolet light. Infrared telescopes help us see things that regular light cannot.

These telescopes work in a very specific way. They use a camera with a special detector. This detector must be kept very cold to work. Scientists call this cooling cryogenic temperatures. This is important because the tools must be sensitive. The telescopes can be on the ground or in the air. They can even sit in space.

Many people helped create this technology over a long time. William Herschel discovered infrared radiation in 1800. In 1878, Samuel Pierpoint Langley made a bolometer. A bolometer is a tool that detects tiny changes in heat. Thomas Edison also used a tool called a tasimeter in 1878. He used it to measure heat from the Sun. Later, Frank Low invented a germanium bolometer in 1961. This helped lead to the telescopes we use today.

There are different places to put these telescopes. Ground telescopes are often on high, dry mountains. This is because water in the air blocks infrared light. In the 1960s, people used balloons to go higher. By 1967, scientists put telescopes on rockets. One big project was the IRAS, which launched in 1983. It showed us the center of the Milky Way galaxy.

Space telescopes are even better for seeing clearly. They do not have to deal with Earth's atmosphere. NASA has a famous tool called the James Webb Space Telescope. It launched on December 25, 2021. It uses power from the sun to work. Another big tool was SOFIA. It was a 17-ton telescope on a Boeing 747 jet.

These tools help us understand the far and dusty parts of space.

An infrared telescope is a specialized instrument designed to detect celestial bodies using infrared light. This light is a specific type of radiation found within the electromagnetic spectrum. Every object in the universe with a temperature above absolute zero emits some form of electromagnetic radiation. Scientists utilize many different types of telescopes to study these various emissions. These include tools for gamma rays, X-rays, ultraviolet light, and regular visible light, which is also called optical light. Infrared telescopes allow astronomers to observe the far, the cold, and the dusty parts of our universe.

To function, these telescopes use an infrared camera equipped with a solid-state infrared detector. This detector must be cooled to cryogenic temperatures to work properly. Cryogenic temperatures are extremely low temperatures required to maintain the sensitivity of the instrument. The mechanism relies on detecting radiation that would otherwise be lost to heat interference. By keeping the detector cold, the telescope can accurately capture the faint infrared signals from space. This process allows scientists to see objects that do not emit much visible light.

There are three main types of infrared telescopes based on where they are located. The first type is ground-based telescopes, which were the first used to observe the infrared universe. These became very popular during the mid-1960s. The second type is air-borne telescopes, which fly at high altitudes to get above much of the atmosphere. The third type is space-based telescopes, which operate entirely outside of Earth's atmosphere.

Placing telescopes in space is highly effective because it eliminates interference from the Earth's atmosphere.

Ground-based telescopes face a specific challenge because water vapor in the atmosphere absorbs infrared radiation. To combat this, scientists often place these telescopes on high mountains in very dry climates. This helps improve visibility by reducing the amount of water vapor in the way. In the 1960s, researchers experimented with using balloons to lift telescopes to higher altitudes. By 1967, scientists began placing infrared telescopes on rockets. These rockets served as the very first air-borne infrared telescopes in history.

The history of this technology involves many important scientific discoveries and inventions. In 1800, William Herschel discovered infrared radiation. Later, in 1878, Samuel Pierpoint Langley created the first bolometer. A bolometer is a sensitive instrument that can electrically detect tiny changes in temperature within the infrared spectrum. During the same year, Thomas Edison used a device called a tasimeter to measure heat in the Sun's corona. In the 1950s, scientists began using lead-sulfide detectors cooled with liquid nitrogen. Between 1959 and 1961, Harold Johnson developed near-infrared photometers to measure thousands of stars. Finally, Frank Low invented the germanium bolometer in 1961. This specific invention, which was cooled by liquid helium, paved the way for modern infrared telescope development.

Many significant projects have utilized these advancements to expand our knowledge. The Infrared Astronomical Satellite, or IRAS, launched in 1983 and provided vital information about other galaxies. It also revealed details about the center of our own Milky Way galaxy. In May 2010, NASA launched the Stratospheric Observatory for Infrared Astronomy, known as SOFIA. This was a massive 17-ton infrared telescope mounted on a Boeing 747 jet airplane. More recently, NASA launched the James Webb Space Telescope, or JWST, on December 25, 2021. The JWST is a solar-powered spacecraft that continues to study the cosmos.

Different telescopes are designed to look at different wavelengths of light. Typical infrared astronomy covers a range from 0.75 to 1000 micrometers. This range includes far-infrared and submillimetre astronomy. For example, the Spitzer Space Telescope operated between 3 and 180 micrometers. The Herschel Space Observatory looked at even longer wavelengths, from 55 to 672 micrometers. By using these different scales, scientists can build a complete picture of the physical world and the stars.