VB, thank you for your courtesy, but this is an informal and friendly forum, and it is not necessary to call anyone by titles or honorifics. My name is Jon, not "Sir". Some people who participate here are still at school, others are professors or professionals with advanced skills. It makes no difference. What matters is to be polite, have fun, and be helpful when you can. No one knows everything and everyone has something to tell.

Another thing. You have an active mind, as we can tell from your questions. That is good. However, a good question is like a recipe for a cake; no matter how good the ingredients,  if you do not bake it long enough it is not good for your guests (nor for you). When you think of a question, do not run for the keyboard; write it down and think about it. Keep it for the next day and sleep on it. Maybe by the next morning you will have worked out part of the answer. Even if it is a small part, even if it is wrong, that is better than just asking without thinking. 

Then, when you prepare to ask the question, stop and ask yourself what sort of answer would help you. Here you asked a question about landing on the sun. That one was all right; you didn't know that the sun is not solid, nor even liquid, and that we therefore cannot land there. Maybe you had expected an answer like: "The sun's surface is too bright and too hot; you would need dark glasses and reflective, insulating clothing; Oh, and a very powerful spaceship!" Well, that would be a reasonable thing to expect, so that was a reasonable question. The fact that it is the wrong answer does not make it a bad question. I was able to help you with a more accurate answer. That is why you asked.

But think of a question like "In future what will  be the highest speed of internet connection on earth?" Never mind what you know or don't know; never mind whether we have any way to find out, ask yourself what answer would fit:

"100.' 'Ten tonnes." 'More than you need.' 'It doesn't matter; the internet stops next month.' 'Future internet will be connectionless.' 'With or without broad-band?" 'Trunk or WiFi?'

Do you see what I mean? If you do not explain what made you ask, what you want to do with the answer, and so on, you cannot expect your forum companions to give a useful or meaningful answer.

You did better with the questions of alien attack, but even there you began by assuming that they would attack. You then realised that they might also be friendly. When you realised that, you should not have added it to the question, you should have stopped, worked out the question, and only then asked.

Next time you prepare a question, try writing it down first. Then imagine that a young friend of yours had asked you the question. Do your best to answer it. Notice what you get stuck on, the things you do not know or do not understand. If you can, try to look up the answers on Google or Wikipedia.

Then ask us. You will ask better questions, get better answers, and understand the answers better. You also will enjoy it more; trust me! So will we. We will learn more from the questions for a start.