Raising the energy state of an atom's nucleus using a laser, or exciting it, would enable development of the most accurate atomic clocks ever to exist. This has been hard to do because electrons, which surround the nucleus, react easily with light, increasing the amount of light needed to reach the nucleus. By causing the electrons to bond with fluorine in a transparent crystal, UCLA physicists have finally succeeded in exciting the neutrons in a thorium atom's nucleus using a moderate amount of laser light. This accomplishment means that measurements of time, gravity and other fields that are currently performed using atomic electrons can be made with orders of magnitude higher accuracy.