Holmdel Horn Antenna

The Holmdel Horn Antenna is a radio telescope in Holmdel Township, New Jersey, built from an aluminum structure roughly 50 feet long with a 20 by 20 foot aperture mounted on a wheel about 30 feet across. The whole assembly sits on a rotating steel frame that allows precise pointing toward different parts of the sky.

Arno Penzias and Robert Wilson discovered cosmic microwave background radiation here in 1965, a signal left over from the Big Bang. This finding earned them the Nobel Prize in Physics in 1978 and reshaped our understanding of how the universe began.

The horn shape gives this installation its name, designed to collect and focus radio waves from space with minimal interference. Scientists visit to trace how radio astronomy evolved and to study the engineering that opened new chapters in understanding the cosmos.

The site lies in Holmdel Township and was purchased by the municipality in 2023, with plans to convert the grounds into a public park. Visitors should check ahead for updates on construction work, as access may vary depending on ongoing improvements.

The installation rotates on a circular track and tilts up and down, allowing observers to aim at different regions overhead. This mechanical flexibility proved crucial for isolating faint signals from space amid earthly interference.

Location: New Jersey

GPS coordinates: 40.39072,-74.18483

Latest update: December 5, 2025 22:30