X is for…
NASA’s Picture Dictionary
Check out what X stands for…
X-ray
An invisible kind of light that can go through most solid objects.
The Crab Nebula is a cloud of particles and dust in space. The picture on the left is the Crab Nebula in light you can see with your eyes. The picture on the right is the Crab Nebula seen with X-rays.
NASA
Sentences:
Doctors can use X-rays to see people’s bones.
NASA uses X-ray telescopes to see parts of space that are really hot.
