Happy Birthday, Hubble: Seeing the Universe in a New Light


If you are at all interested in astronomy, chances are you’ve already heard that the Hubble Space Telescope is celebrating its
The Electromagnetic Spectrum. NASA’s Great Observatories (Compton, Chandra, Hubble and Spitzer) and the electromagnetic thermometer scale. (Credit: NASA/CXC/M.Weiss)

The four Great Observatories, in order of their launches that took place between 1990 and 2003, are Hubble, the Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the Spitzer Space Telescope.

A photo of the Hubble Space Telescope, doing its job in space. Credit: NASA

NASA’s Hubble Space Telescope was launched on April 24, 1990. Hubble has four main scientific instruments that allow it to observe not only in visible light but also near ultraviolet and near infrared. Hubble helped determine how old our Universe is, what quasars are, and also helped discover “dark energy.”

The space shuttle crew took a photo of the Compton Gamma Ray Observatory as the satellite was deployed, with Earth visible beneath it. Credit: NASA/MSFC

In 1991, NASA launched a satellite into space carrying the Compton Gamma Ray Observatory (CGRO). The goal of Compton was to study gamma rays from objects far out into space. Gamma ray telescopes can study incredibly exotic objects such as blazars, magnetars, cosmic rays, and dark matter. Compton operated in space until when NASA intentionally sent it into the Earth’s ocean in 2000.

An artist’s illustration of the Chandra X-ray Observatory in space. Credit: NGST

NASA’s Chandra X-ray Observatory is a telescope specially designed to detect X-ray emission from very hot regions of the Universe such as exploded stars, clusters of galaxies, and matter around black holes. Because X-rays are absorbed by Earth’s atmosphere, Chandra must orbit above it, up to an altitude of —> Read More