Put the summary notes in the correct order.

• 1.3 billion years ago, two black holes locked into a spiral and collided, releasing an enormous amount of energy in a very short time.
• However, their energy could not turn into light, so it caused gravitational waves.
• From that moment until the present, life on Earth has evolved significantly.
• Only about 25 years ago, a group of scientists from leading research centres came up with an idea of a laser detector to explore the gravitational waves.
• The US National Science Foundation agreed to fund the project and the detector was constructed.
• It was named LIGO: The Laser Interferometer Gravitational-Wave Observatory and over the years, it has greatly improved its accuracy.
• On September 14 of 2015, the gravitational waves from the black holes colliding 1.3 billion years ago passed through our planet and were detected by Advanced LIGO.
• Scott Hughes, a theoretical physicist at MIT studying gravitational waves, says that this breakthrough was one of the landmark events of his life.