Hubble Space Telescope
Hubble is one of the most important scientific instruments ever built - an orbiting observatory that has transformed our understanding of the cosmos. Operating above Earth's atmosphere's distortion, it has provided crystal-clear views of the universe for over 30 years, from planets in our solar system to galaxies 13 billion light-years away.
Overview
Hubble is 13.2 meters long, weighs 11,100 kg, and orbits Earth at 547 km altitude. Its 2.4-meter primary mirror was ground to precision tolerances of 10 nanometers - but the wrong spacer led to spherical aberration, requiring the famous COSTAR corrective optics deployed in 1993.
Key Discoveries
- Age of Universe: Precisely measured the Hubble constant, determining universe is 13.8 billion years old
- Black Holes: Discovered supermassive black holes at centers of galaxies
- Cosmological Constant: Evidence for accelerating expansion of universe (dark energy)
- Exoplanets: First direct image of exoplanets around Fomalhaut
- Distant Stars: Observed individual stars 9 billion light-years away
- Solar System: Detailed studies of all planets from Mercury to Pluto
Servicing Missions
Hubble was uniquely designed for servicing by Space Shuttle astronauts - the only telescope that could be upgraded in orbit. Five servicing missions between 1993 and 2009 installed new instruments, replaced failed components, and extended the telescope's capabilities far beyond its original design.
Communication
Hubble communicates with Earth through the Tracking and Data Relay Satellite System (TDRSS), sending approximately 120 GB of science data per week via solid-state recorders. The telescope's high-gain antenna provides 1-2 Mbps downlink to ground stations.
Legacy
Hubble has made over 1.5 million observations, published over 18,000 peer-reviewed scientific papers, and its data is cited more than any other scientific facility in history. It has revolutionized astronomy across all wavelengths from ultraviolet through visible to near-infrared light.
Illustrations
