This question comes from me. It's a new chapter from the 10th anniversary edition of What If, which is now available online and in print.
At the end of the laser pointer video, we constructed an array of lasers with a total power of 2·10^24 Watts, which not only lit up the moon but violently ejected it from orbit around the Earth.
We decided that was enough power. But why? You can always make a number bigger. No one can stop you. There are infinitely many numbers.
And I want to know what if we tried even more power? A 2.10^24 W laser is powerful.
When we turned ours on, it made the moon facing surface of the Earth significantly more luminous than the sun. That's impressive, but we can do better.
The universe contains death rays that make our moon obliterating beam look like a handheld laser pointer gamma-ray bursts.
A gamma ray is just what we call a very high energy photon of electromagnetic radiation.
When you see a chart of the electromagnetic spectrum, gamma-rays are basically anything more energetic than X-rays. At the high end, they're literally off the chart.
They come from high energy events like nuclear explosions. Gamma-ray bursts are made when something very bad happens to a star.
When massive stars collapse, their cores give into the crushing pole of their own gravity, release an enormous burst of energy, and tear the star apart from the inside.
