Detailed Instructions: In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.
Problem:Article: The plan: turn Mars into a blue world with streams and green fields, and then fill it with creatures from the earth. This idea may sound like something from a science fiction , but it is actually being taken seriously by many researchers. This suggests the future for the "red planet" will be the main topic for discussion at an international conference hosted by NASA this week. Leading researchers as well as science fiction writers will attend the event. Turning Mars into a little earth has long been a topic in science fiction," said Dr Michael Meyer, NASA's senior scientist for astrobiology ."Now, with scientists exploring the reality, we can ask what are the real possibilities of changing Mars." Most scientists agree that Mars could be turned into a little earth, although much time and money would be needed to achieve this goal. But many experts are shocked by the idea. "We are destroying our own world at an unbelievable speed and now we are talking about ruining another planet," said Paul Murdin from the Institute of Astronomy, Cambridge, UK. Over the past months, scientists have become increasingly confident .They will find Martian life forms. Europe and America's robot explorers have found proof that water, mixed with soil, exists in large amounts on the planet.
Answer: the necessity of changing Mars
Solution:
The passage is about _ .