Friday the 5th of August saw Ed Daw of Sheffield University give us a talk on the FIRST DIRECT DETECTIONS OF GRAVITATIONAL WAVES BY LIGO. (Laser Interferometer Gravitational-wave Observatory)

He has been working on the project for 19 years and told us of the difficulties of building the detector. Even getting it straight on the curved surface of the Earth was a problem. They even had to compensate for the pull of the Moon’s gravity!

He made the story funny and even made the maths humorous. They even had to contend with crocodiles in the water filled channels which run down the sides of the concrete tubes housing the detector, which can be seen in the above image.

When the LIGO experiment, conceived in 1972 by Rai Weiss at MIT, had successfully detected gravitational waves from binary black hole collisions approximately 100 million light years away, it was met with apprehension. The first wave came through on the 14th September 2015. They spent weeks checking whether it was really the gravitational wave or a misinterpretation of the data. Ed said the hardest part was not being able to say anything until the official announcement was made in February of this year.

The second wave to come through again took everybody by surprise. It was on Boxing Day and at the time Ed was caving and didn’t know until he surfaced and read his emails later. This time they knew what they were looking for.

Ed is obviously very enthusiastic about his work and this shone through in his talk. He enjoyed the questions and was surrounded after the talk by members wanting to know more. He was very complimentary about our telescope calling it “some feat of engineering”.

You can learn more about LIGO at this website:

https://www.ligo.caltech.edu/

Our thanks to Ed for giving such an entertaining talk about this amazing project.