Yes, it is. That is correct.
True. All measurements are to some decree uncertain, as one cannot know for sure that the measured value is that exact value, even if you using a device that gives very precise measurements to the greatest number of significant figures.
1. gravity (gravitational pull from the sun brings all the planets into orbit)
2. the big bang.
3. hydrogen gas.
4. planets, moons, asteroids, and comets
5. it’s becomes a black dwarf star
Radio and microwaves have longer wavelengths than visible light. If you go take a look at the electromagnetic spectrum, you will be able to see that visible light waves have a higher frequency and a shorter wavelength (

).