Chapter 24 - 24.7

The first, indirect detection of gravitational waves in the 1970s involved

a pulsar that was in the same star system with a neutron star

What is a key reason that gravitational waves are so much harder to detect than electro-magnetic (e-m) waves?

gravitational waves are much weaker than e-m waves, and therefore require very, very precise equipment to detect

Some years after college (and after you recover from your astronomy class,) you get married and exchange gold rings with your sweetheart. What connection is there between the gold in those rings and recent observations of gravitational waves?

our new understanding is that significant amounts of gold in the universe are produced in the mergers of neutron stars, which can be detected with gravitational waves

In the first direct detection of gravitational waves by LIGO in 2015, the waves came from

the merger of two black holes

The first time that astronomers observed both gravitational waves and electro-magnetic waves from the same event, what they were observing was:

the spiraling toward each other of two neutron stars