August 27 - Go outside and check - Mars is NOT the size of the Moon tonight!

Posted on August 27, 2018

A few nights ago, my husband spotted a bright reddish star near the Moon in the South-Southeastern sky. This was shortly after sunset, and there were pretty much no other stars in still-light sky. My husband thought the reddish "star" was actually the planet Venus and wondered why it looked so red.

I followed his pointing finger and knew the star wasn't Venus. I wondered if it could be an airplane that happened to be heading our exact direction, and so we couldn't see movement across the sky. "Or Mars...?" I said.

The question mark was because I didn't think it could be Mars, because it was too bright.

Venus in its Evening Star role.
The reason I knew that it could not be Venus was that Venus is closer to the Sun than we Earthlings are, so it can never appear on the opposite side of the sky from the Sun. When we see Venus in the evening (Evening "Star"), it's a very bright starlike object in the West; when Venus is the Morning "Star," it comes up in the East a few hours before sunrise.

My husband seemed skeptical about all of that, but we soon reached a spot when a break in the trees allowed us to see the still-glowing Western horizon, and in those Western skies we could clearly see the planet Venus, even brighter and distinctly whiter than the red something my husband had spotted.

I looked back. The red something couldn't be a plane - it still hadn't moved or grown in size. It must be Mars - but why was it so bright?

When I checked out our observations using Google, I discovered that Mars is brighter in Earth's skies right now because it is closer to the Earth. The closest approach of the two planets - closest in 15 or so years - occurred on July 27. It was and would remain the second brightest planet in our skies until September 7, when the farther-away but MUCH larger Jupiter would become the second brightest planet again.

Star charts like this one help us to figure out what we are
seeing in our night skies. Notice the directions indicated at
the bottom - West, SouthWest, South, SouthEast.

All those Moons are dated; this tells us what phase of the
Moon we can expect on what day, and also the relation of the
Moon to the various planets and constellations on each date.

Double Moon???

When I checked out why Mars seemed so bright, I discovered that there is a "Mars Spectacular" post / meme / whatever that circulates through social media every year around this time. Before Facebook was Facebook, this same story was circulated around through email. The story was that, on August 27, something could be seen that no human had ever seen before -

- Mars would be SO big and so bright, it would appear as large as the Moon - 

- and of course the Moon would still be the Moon, so we would see two Moons!!

Of course this post or meme would generally have a photo showing Earthly skies with two Moons.

Of course, this is impossible. I wondered if it could be just a giant misunderstanding, and it turns out that the Mars Spectacular is based on some half-truths, and now we're getting down to why this post is happening today of all days:

Back on this date in 2003, Mars was closest to Earth as it had been in almost 60,000 years! So that was a much, much rarer sighting!!! But...

(There's always a "but"...)

The brightness of Mars on that particular night was only a little bit brighter than what we are now seeing, and Mars still appeared as just a bright, reddish starlike object.

It was not the size of the Moon - as a matter of fact, it's only 1/140th of the size of the Moon! Of course, it was not nearly the brightness of the Moon, either!!

This enormous exaggeration of a cool astronomical sighting is a hoax, and it's a hoax that keeps coming back each and every August. Every August people call up astronomers and observatories and astronomy magazines - and they ask about the upcoming Mars Spectacular.


As one blogger wrote recently, in answer to a question about whether or not Mars was really going to look like the Moon's twin:

"[It's] just not true. It’s not true in 2018. It’s never been true. It never will be true."

Also on this date:

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