This comes around at least once a year, so let's just get right to it.
Mars will not appear "as large as the Moon" in the sky on August 27.
Why do people think that it will? Because this image is going around on Facebook.
This image is a variation on a hoax which began back in 2003, and has been repeated every year since. It apparently began because at that time Mars was relatively close to the Earth, and would look "as large as the Moon through some telescopes". That last bit was dropped off, the image was edited, and… here we are.
In its current form the hoax claims that "this will not happen again until the year 2287" and that no one alive had ever "witnessed this happening".
Given the fact that this obviously not true fact appears in a pre-made Photoshop image, many people have naturally fallen for it again.
So here are some brief reasons why it isn't true.
- There is no full moon on August 27. It will only be a thin waxing crescent Moon.
- Mars is currently moving away from the Earth, after a relatively close pass at the start of the year
- As of August 27 Mars is more than 1.34 times as far away from Earth, as the Earth is from the Sun
- Mars will appear 250 times smaller than the Moon tonight
So there we are. Hoax. Fun. But hoax. Carry on.