This is more of a historical background in astronomy and the phenomena that we will be watching in this awesome video #2 (the most powerful objects):

Energy comes from a Greek word for activity or working. In physics, it’s simply the property or the state of anything in our universe that allows it to do work. Whether it’s thermal, kinetic, electro-magnetic, chemical, or gravitational.

The 19th century German scientist Hermann von Helmholtz found that all forms of energy are equivalent, that one form can be transformed into any other. The laws of physics say that in a closed system – such as our universe – energy is conserved. It may be converted, concentrated, or dissipated, but it’s never lost.

Were you aware of that historical background?

And let’s us see if you got some or all of the objects in the video correct before watching?

We hope you enjoy and check back for more cool space vids!