While on a space mission to Neptune, you accidentally broke your tether on the way. After a couple of hours floating, you were hit by an asteroid.
You passed out.
When you are conscious again, you met me. I offer to bring you back to your home with my ultra-speed spaceship.
The problem is, you don't have any pen, paper and no Pioneer plaque with you. You have to somehow tell me where to take you. I also want to visit your planet.
You know that for you to leave Solar System, you must have been unconscious for a long long time. You feel hunger, but not starving. Therefore, you should not be too far away from the place asteroid hit you.
You can see around, you can point the direction you want to go, and I guarantee that I will avoid any collisions on the way (so you don't have to worry about pointing at the right direction at a wrong time).
You need to observe your surroundings very carefully and tell me which way to go. But be careful, a wrong turn might get both of us lost.
Since your tether was broke, you only have what an astronaut brings out of space vehicle.
You are able to show and tell, but not able to draw and explain the units.
You need a very precise method to get back to earth. A common way to get lost is "I'll figure out how to get X when I get to Y."
Even if you memorized the position of all planets during your mission, you have no idea where they are now because you passed out for some time.
If you assume that you can distinguish the sun from that distance, then you also should show how (either a photo or some mathematical demonstration).
Even if I know where the Earth is, I cannot know without proper observation. And I do not have that technology near me. Just like you don't have your technology with you to know where any planet is right now.
- You cannot just say "go to Mars and we will find Earth. I have no idea what is Mars and what is Earth.
- You are near Neptune. Which means, until you provide a solid argument, I will assume you don't know where any planet is. That argument might be "I saw a picture taken by Voyager and in that photo Mars is seen like this." But I will not believe you if you say "I can 100% tell where Earth/Mars/Jupiter is." I don't want to get lost into Solar System.
- I do not have anything with me. You cannot just assume that my species invented any material for you to write. I even don't know this word. We communicate using brain waves.
- For the last time, provide exact series of actions to go to Earth. I will not accept "just go towards Sun, and it is the blue/third one." If you were in my shoes, would you waste your energy and time based on this vague description? I think not.
- You are an astronaut. Therefore, you have no pockets, no bags, nothing. This is how you Earthlings behave. We don't need no space-suit. You need. But you put no pockets on your suits. It is not my fault. So please stop telling me "it is very absurd I don't have anything with me."
- If you know where the planets are right now, then you need to prove it. You may assume that you passed out for a couple of hours or a couple of days, but you have to tell me where is your home based on your current position in space.
To sum up, stop telling me how easy it is and point me the way!
TL;DR You are lost in solar system. How can you find where the Earth is?