1. Radio Waves
Radio waves are one type of electromagnetic wave, ranging from about one foot long to several miles long. This type of electromagnetic frequency is used to transmit data and are used for satellites, computer networks and radio.
Atoms are the smallest building blocks of matter and everything in the observable universe is made of trillions of atoms. Although atoms have never been seen with the human eye, they can be indirectly observed.
3. Dark Matter
Dark matter does not emit light or energy, yet it can be observed by calculating the motion of planets. About 80% of matter in the Universe is made up of dark matter.
Antimatter possesses qualities that are opposite to normal matter. When matter and antimatter meet, both are annihilated. How do we know it exists? Through the world’s particle accelerators and other various scientific tools.
OK, this is pretty obvious, but it’s amazing that something we can’t even see is responsible for keeping us alive.
6. Ultraviolet Light
Ultraviolet light is a type of electromagnetic wave that is responsible for sunburn! Some animals, such as bumblebees, can see ultraviolet light, but we can’t. The Hubble Space Telescope also uses ultraviolet light to see galaxies and stars in space.
We can measure it, but we can’t observe it.
Whatever, gives off heat radiates infrared waves, e.g. the human body. Infrared is a type of electromagnetic wave.
9. The Mind
We can observe the brain and its chemical reactions, but thoughts are completely intangible to us.
We can see the expression on people’s faces, observe their body language, and watch different parts of the brain react to feelings, but emotions are completely intangible.
11. Quantum Particles
Quantum, or virtual particles exist on a subatomic level (i.e. they’re smaller than atoms). Scientists theorize that they literally pop in and out of existence for brief moments of time. They can only be understood through magnetic or electrostatic forces.
12. The Entire Universe
We know that it’s out there. We can see a fraction of it with telescopes. But we can’t see or even fathom the entire extent of the universe (and whether it actually ends). How mind-bending is that?
By Aletheia Luna