Space telescope hubble photograph

The Hubble Space Telescope has revolutionized astronomy since its launch in 1990, capturing stunning images of the universe.

About this subject

The Hubble Space Telescope, a joint project of NASA and ESA, was launched on April 24, 1990, aboard the space shuttle Discovery. Orbiting Earth at about 547 km altitude, it operates outside the atmosphere, allowing it to capture sharp images without atmospheric distortion. Hubble was designed for observations in visible, ultraviolet, and near-infrared spectra, making it essential for astrophysical studies.

Among its most notable contributions are determining the universe's expansion rate (Hubble constant), discovering that this expansion is accelerating (indicating dark energy), and iconic images like the Pillars of Creation in the Eagle Nebula. It also helped date the universe's age at about 13.8 billion years and observed galaxies more than 13 billion light-years away.

Beyond science, Hubble has had a huge cultural impact. Its colorful images are often used in science outreach, inspiring generations. Despite initial mirror problems corrected in 1993, the telescope underwent several servicing missions, extending its lifespan. It is expected to operate until the late 2020s, complemented by the James Webb Space Telescope.

Interestingly, colors in Hubble images are often added to represent specific wavelengths, as original sensors capture in black and white. This coloring follows scientific standards to highlight details, not merely aesthetic. The name honors astronomer Edwin Hubble, who discovered the universe's expansion in the 1920s.

Frequently Asked Questions

What was the biggest problem Hubble faced after launch?

Hubble's primary mirror had a spherical aberration, causing blurry images. In 1993, a servicing mission installed COSTAR, a corrective optics system, restoring sharpness.

How many servicing missions did Hubble receive?

Five servicing missions were conducted by space shuttles between 1993 and 2009, with the last (STS-125) installing new instruments and extending the telescope's life.

Is Hubble still operational?

Yes, Hubble continues operating in 2025. Although surpassed in infrared sensitivity by the James Webb Space Telescope, it still performs observations in visible and ultraviolet light.