The rocket station near Thiruvananthapuram where India's space programme began, with the launch of a Nike-Apache sounding rocket on 21 November 1963.
TERLS launches sounding rockets: rockets that fly up, measure the upper atmosphere and fall back, without reaching orbit. ISRO says its sounding rockets are launched from both Thumba and Sriharikota.
Thumba was chosen because it lies close to the Earth's magnetic equator. That made it a good place to study the equatorial electrojet, a narrow belt of electrons flowing high above the magnetic equator.
TERLS was set up in 1962 with UN sponsorship, in a coastal village near Thiruvananthapuram. A local church, St Mary Magdalene's, was given by the villagers and became the office and laboratory.
On 21 November 1963, a two-stage American Nike-Apache rocket lifted off from Thumba. It was the first rocket launched in India. India's own first sounding rocket, the RH-75, followed on 20 November 1967.
Prime Minister Indira Gandhi dedicated TERLS to the United Nations on 2 February 1968. The US, the USSR, Japan, France and Germany later launched their own sounding rockets from here. From 1970 the USSR launched a weather rocket, the M-100, every week until 1993.
As rockets grew, Thumba became too small, so India built a second station at Sriharikota.
Thumba is still in use. In November 2023, at the 60th anniversary of the first launch, a Rohini RH-200 became the 2,452nd sounding rocket launched from Thumba. TERLS has been part of the Vikram Sarabhai Space Centre since 1972.
The old church was later turned into a space museum. VSSC says it draws regular crowds of students and the public.