Painters painting the GBT's surface

Ants on a Plate

From over 200 feet above them, painters look like ants on the 2.3 acre dish of the Green Bank Telescope. Each of the 2004 aluminum panels of the GBT’s surface must be scraped and repainted on a rotating schedule. It takes years to paint the entire telescope, and painters arrive every summer to keep this endless task going. The paint on the GBT is a special blend that reflects sunlight, gives off heat, and its molecules do not give off radio waves.

The GBT

You Can’t Miss It

The Green Bank Telescope dominates the countryside in Green Bank, West Virginia. At 485-feet tall and over 2 acres across, the GBT is the largest moving land-based object ever built.

Made in America

The Green Bank Telescope is an American treasure. The GBT is the world’s largest, fully-steerable telescope, and anyone can come visit it in Green Bank, West Virginia.

Actuator Motors

Each of the Green Bank Telescope’s 2004 surface panels is adjusted by a small, computer-controlled motor called an actuator, seen here at the edge of the dish. The 2.3-acre surface of the GBT requires 2209 actuators to maintain its accurate surface shape.

Giant in the Mist

Nearly every dawn sunrise in Green Bank is blanketed in fog. The Green Bank Telescope (GBT), 485-feet high, is only just peaking up over the morning mist.

Keeping in Shape

Both the 100-meter dish and this smaller subreflector of the Green Bank Telescope must maintain their perfect shapes to properly bounce radio waves into the GBT’s receivers. An array of little reflectors help engineers gauge the shape of this smaller dish.