Fermion
The speed of sound in seawater is around 1500m/s or 5400 km/hr. Something tells me they won’t actually be going supersonic.
The article shouldn’t be referencing the speed of sound without specifying the medium for the sound waves and conditions such as temperature for water or temperature and pressure for air.
Harvard is a $50 Billion endowment fund that happens to run a school. So Harvard divesting from Israel affiliated investments is potentially significant.
A relay switch could work. You would put the car 12V and ground across the coil connections, the 12V on the NO connection, the panel on the NC connection, and the power pack on the C connection. Make sure you get a 12VDC relay.
Are you going to have the panel installed permanently on your car?
Definitely don’t connect a 24V source directly to your cars 12V system. There’s a good chance of frying something important. A fuse would not protect from overvoltage so don’t rely on those to protect components.