OMG!!! Mars Will Be as Big as the Moon!!!! (NOT)

The Mars/Moon Hoax Rears its Ugly Head

Well, the hysterical claims are starting up yet again. Yes, it’s the annual Mars/Moon madness again. Only this time, the folks claiming that the Moon and Mars will be the SAME SIZE OMG!!! NEVER AGAIN IN THIS CENTURY!!!! are claiming that on August 27th, 2014, we’ll be treated to a view of the Moon AND Mars both the same size in the sky.  The accompany image implies they’ll be *thisclose* in the sky.  The story is so screwed up it’s not even wrong.   But, before I get to work dismantling the latest flight of fancy about this subject, the good news is that there is something neat to see in the sky that night (and indeed, for the next couple of weeks).  I’ll talk about that in a minute.

Here’s a star chart that I made using Stellarium for the period of time just a few minutes after sunset on the 27th. This shows the sky with indicators for where the Moon and Mars will be. They are roughly 45 degrees apart — nowhere near each other, as it turns out.  So, that immediately puts the lie to the images I’ve seen showing two Full Moons next to each other (apparently one of them is supposed to be Mars).

The insets show about how these objects will really look. The Moon will be a very young crescent (NOT FULL, as is shown in some of the graphics I’ve seen). Mars and Saturn will appear as dot-shaped  objects in the twilight. As it get darker, they’ll look brighter (since we won’t be contending with the twilight glow), but by that time, the Moon will have set. The chart doesn’t lie. You can go to Stellarium, download the free program, run it and see for yourself. It’s easy to do.

Where did this huge misunderstanding come from? Apparently someone a few years ago misread (or didn’t understand) an article written about an appearance of Mars in the sky in 2003. The article said that if you looked at Mars through a telescope at that time, the image would be magnified 75x (75 times), and that magnification would make Mars look (through the eyepiece) as big as the Full Moon does to the naked eye. So, the article was making a comparison between two objects, one far away viewed in a telescope and the other closeup viewed with the naked eye (that is, without magnification).

The writer was attempting to show that the Moon looks big to us (it’s close, so it should), and that Mars is so far away (even at its closest) that we need magnification to make it look as the Full Moon does to our naked eyes.  It was a size-distance comparison. During that time (in 2003), Mars was at a point in its orbit where it was closer to Earth than anytime in 60,000 years. So, as most urban legends go, a whole new meme was born. It’s usually expressed with lousy pictures (doctored in Photoshop), lots of exclamatory material, and a complete conflation of misunderstanding about the difference between a magnified view of something and a naked eye view. Here are some facts that put the whole hoaxy story to shame.

1. Mars NEVER gets close enough its orbit to appear the same size as a naked eye Full Moon to us. It always looks like a bright, disk-like point of light to the naked eye.

2. The closest Mars ever gets to Earth is about 54.6 million kilometers (about 34 million miles). Even that close, Mars will only ever appear as a bright dot of light to the unaided eye. If you want to see Mars bigger, you have to look through a telescope, which will magnify the view.

3. Right now (and on the 27th), Mars’s distance from us is about 1.97 million kilometers (about 122 million miles). The Moon is 404,206 kilometers (251,162 miles).

4. At that distance, Mars (which is bigger than the Moon) always appears as a dot of light to the naked eye. To get a better view, you have to magnify.

5.  If Mars ever got so close to Earth that it would appear (to the naked eye) as big as the Full Moon, we’d be in serious trouble. At the distance of the Moon, Mars and Earth would be undergoing some serious tangoing, and not in a fun way.

6. A look at a calendar with moon phases on it will tell you that there’s NO way that there will be a Full Moon on the 27th.

7. Never underestimate the human ability to misread and misunderstand something and then retransmit the misunderstanding to others. If you’ve ever played the game “Gossip”, you’ll understand immediately.

So, there is NO big Mars-as-big-as-the-Moon happening on the 27th. But, there are a couple of planets you can watch until well into the evening. The star chart immediately above gives you the location of the two planets, plus some bright stars in the early evening hours for the next couple of weeks.  Saturn and Mars will look like rounded dots of light. The stars will twinkle and be more point-like.

Check out Mars and Saturn (as shown at right). If you have a good telescope, you can probably see the rings pretty well. Mars is a bit tougher (it’s small), so you’ll mostly see a reddish point of light, unless you have a larger telescope that will let you see a few of the bright and dark areas on the planet.

Check ‘em out! And, don’t buy any wooden nickels, or miracle fat pills, or strange hoax stories you hear about the sky. As with many things in life, if it sounds too good to be true, it probably is. The people who tell those kinds of stories are betting that other people are too stupid to see through their hoaxes. There’s nothing mysterious about astronomy. It’s glorious and inspiring, and it will always show you something new and exciting!