Green Bank Telescope
The Robert C. Byrd Green Bank Telescope (GBT) in Green Bank, West Virginia, is the world’s largest fully steerable radio telescope. It sits in a quiet area known as the National Radio Quiet Zone, which helps it detect faint radio signals.
Built between 1990 and 2000, it began regular science operations in 2001 and was named for Senator Robert C. Byrd, who helped fund it. Since 2016 the telescope has been operated by the independent Green Bank Observatory.
Key features and uses:
- A 100-meter dish with an active, off-axis surface for high sensitivity across 0.1 to 116 GHz.
- Fully steerable, able to view about 85% of the sky.
- Works with major facilities like ALMA, the VLA, and the VLBA, and supports Breakthrough Listen in the search for intelligent extraterrestrial signals.
- Has radar capabilities (ngRADAR) to study Solar System objects.
Technical and size details:
- The telescope weighs about 7,600 metric tons and is 148 meters tall.
- The dish surface area is about 2.3 acres, with 2,209 actuators to keep the surface accurate.
- It operates about 6,500 hours per year, with 2,000–3,000 hours on high-frequency science.
- The site welcomes around 40,000 visitors annually.
Notable achievements:
- Detected new molecules in interstellar space.
- Found a massive neutron star in 2019.
- Used to scan interstellar object ʻOumuamua for signs of alien technology in 2017.
This page was last edited on 2 February 2026, at 21:42 (CET).