20 July 1969: Jodrell Bank telescope tracked Eagle lander onto the surface of the Moon

The Apollo 11 lunar landing mission crew, pictured from left to right, Neil A. Armstrong, commander; Michael Collins, command module pilot; and Edwin E. Aldrin Jr., lunar module pilot. Copyright: NASA.

On this day (20 July) in 1969, the Apollo 11 Eagle lander module containing astronauts Neil Armstrong and Buzz Aldrin became the first manned space mission to land on the Moon.  Fours later on 21 July 1969, Armstrong became the first man to set foot on the moon, issuing the oft-quoted line, “That’s one small step for [a] man, one giant leap for mankind.” Over two-hundred thousand miles away on Earth, the mission was being unofficially monitored and recorded by Jodrell Bank Observatory team using multiple telescopes on site.

From the initial operation of the Lovell Telescope, the telescope had become entwined with the “Space Race”, tracking spacecraft operated by both the Russians and Americans beginning with the world’s first artificial satellite Sputnik 1 in October 1957. In July 1969, the Jodrell Bank Observatory team team, led by the observatory Director Sir Bernard Lovell, used telescopes at the Cheshire site including the Lovell Telescope and the 50ft telescope (now the 42ft telescope) to simultaneously monitor signals from the Apollo 11 Eagle lander and the Russian unmanned module Luna 15 spacecraft both on lunar missions.

Signals intercepted (see below) by the 50ft telescope showed the signals received when Neil Armstrong took manual control of the Eagle lander as well as the moment when the Eagle lander module touched down on the surface of the moon.

This is a chart recording of signals from Apollo 11’s Eagle Lander which were picked up at Jodrell Bank. The graph shows time on the horizontal axis and the frequency of the signal being received on the vertical axis. As the relative velocity between the telescope and the Lander changes, the signal being observed is Doppler shifted to higher or lower frequencies. The first half of the graph in which the signal appears to jump up and down is just where the settings on the receiver are being adjusted. In the second half of the graph you can see a smoother signal which then shows several wiggles up and down. These wiggles show where Neil Armstrong took manual control of the Lander to fly it over uneven ground. The signal then becomes a straight line when the Eagle finally lands on the Moon’s surface. The slowly changing frequency is then just due to the relative velocity between the telescope and that point on the Moon’s surface.

Meanwhile – and little known at the time – the Russian unmanned module Luna 15 spacecraft was orbiting the moon on the day of the Eagle landing with a mission to gather samples of lunar soil and rock to bring back to Earth in advance of the manned Apollo 11 mission. Jodrell Bank observatory staff listened in using the Lovell Telescope as the Luna 15 unintentionally crash-landed on the moon’s surface at 3.50pm (UTC) on July 21, just hours before the Americans lifted off from the moon’s surface and departed.

In 2009, dramatic and previously unheard recordings of the Russian lunar activities were uncovered in archives while Jodrell Bank astronomers were researching material to celebrate the 40th anniversary of the Moon landings. The recordings were made over three days in the Control Room of the famous Jodrell Bank Observatory, where astronomer Sir Bernard Lovell and colleagues were listening to the multiple transmissions coming from the moon. Sir Bernard Lovell can be heard narrating events with transmissions from the Apollo 11 astronauts in the background.

In the recording, Sir Bernard notes a change in the orbit of Luna 15 to take it closer to the US landing site and later reports a rumour from a ‘well-informed source in Moscow’ that the craft is about to land. People in the Control Room can then be heard exclaiming ‘it’s landing’ and ‘it’s going down much too fast’ as they track Luna 15’s final moments before it crashes. A voice is later heard saying: “I say, this has really been drama of the highest order.”

Greatest Moment of Time, The Times, 21 July 1969

These echoed comments about the US lunar landing made by Lovell on the same day in an article “Greatest Moment of Time”, published in the Times on 21 July 1969:

The moment of touchdown was one of the moments of greatest drama in the history of man. The success in this part of the enterprise opens the most enormous opportunities for the future exploration of the universe.

Jodrell Bank observatory had a crucial role in this historic moment in the “Space Race”, monitoring and recording big and small moments of lunar exploration by the Americans and the Russians as well as independently verifying the US manned lunar landing.

Blogger: Dr Elizabeth Bruton is Heritage Officer at Jodrell Bank Discovery Centre.

The heritage work at Jodrell Bank is supported by the Heritage Lottery Fund as part of our ‘First Light at Jodrell Bank’ project.