Space-Based Telescope Design, Features and Observatories

Introduction to Space Telescopes

A space telescope is an important astronomical tool that is located above the Earth’s atmosphere.
By being located in space, these telescopes bypass atmospheric distortion and can capture higher resolution images in a broader range of wavelengths.
Space telescopes observe in parts of the spectrum that cannot penetrate our atmosphere, providing unique scientific insights.

Key Features of Space Telescopes

The Objective Lens or Mirror: This is the main light-gathering component; its size determines the amount of light the telescope can capture - the aperture.
The Detector or Camera: This converts the collected light into an image or data, allowing scientists to analyse the observations.
Tracking Systems and Thrusters: Space telescopes need to precisely track objects as they move, maintaining their position and orientation in space.
Data Transmission: Data collected by the telescope are sent back to Earth, typically through a radio link with a space network.

Common Designs of Space Telescopes

Reflector Telescopes: These use mirrors to gather and focus light and are more common in space applications due to their simple design and large apertures.
Refractor Telescopes: These use lenses to gather and focus light. Their use in space is limited due to size constraints and difficulty in scaling up.

Famous Space-Based Observatories and Their Contributions

Hubble Space Telescope (HST): Launched in 1990, the HST has provided some of the most detailed images of distant galaxies, nebulae, and planets in our solar system. It has greatly contributed to our understanding of the universe’s age, the existence of dark energy, and the rate of the universe’s expansion.
Chandra X-Ray Observatory: This focuses on the observation of celestial bodies that emit X-rays, such as black holes, quasars, and high-temperature gases in clusters of galaxies.
Spitzer Space Telescope: Specialised for infrared observation, it helped in the study of galaxies’ formation and evolution, and the discovery of exoplanets.
Kepler Space Telescope: Dedicated to finding exoplanets, Kepler confirmed over 2,600 planets outside our solar system in its nine-year mission.
James Webb Space Telescope (JWST): Its launch anticipated in 2021, the JWST will look further into our universe than ever before, observing some of the first galaxies formed and studying the atmospheres of exoplanets.

Understanding the design, features and contributions of these space-based observatories provides profound insight into the way we explore the universe and deepen our knowledge of it.