If we look at Mars, there are many signs it was once like Earth. If we look at Venus, there are many signs it will be like Earth. All it really needs is to lose a large portion of its atmosphere (from a shockwave event such as a planetary supernova), to gain rotation (from the same event), and to be pushed into a different orbital position (from the same event). This same event would make Earth be like Mars, coated in iron-oxide and stripped of its atmosphere, covered in scars from the immense amount of debris, and shoved outward in its orbital position.

All systems function the same. All systems are capable of supernova. Mercury has a highly dense iron core, a telling condition of a system on the verge of supernova. Also, it is known to be physically shrinking in size, a sign its of components becoming more and more dense due to runaway production of iron.

Venus is what we should be focused on. Going to Mars is like going to post-apocalyptic Earth.

If you are interested, I have compiled evidence from science and prophecy that all connects through this concept to a point where I believe it is the reality of the situation, in my papers Judgment Day and Hidden Mysteries.