It’s August and we’ve been getting calls at Clark Planetarium from people wondering if Mars will appear as large as the Full Moon this month.
So goes our yearly battle with the Great Mars Hoax that started in 2003. Each year, several emails make their rounds, promising that Mars will amaze and delight, appearing as large as the Full Moon.
We originally posted the article below in August 2009, but wanted to help educate our new readers this year, so we’re posting it again…
This often begins in May or June and continues until early September. We’re sorry, we wish we could get them to stop, we really do!
In August 2003, Earth and Mars were closer together than they had been or would be again for thousands of years…and Mars looked really good through a decent sized telescope. You could even see a little surface detail! (light and dark regions). But to the casual observer, it was just a bright red dot in the night sky. Usually, though, Mars is far from spectacular, not exceptionally bright or even interesting in a small amateur telescope– and that’s the case here. Let me explain.
These hoax emails use many astronomical terms in order to sound credible, but often incorrectly. They talk of azimuth, altitude, opposition etc but ignore Mars’ actual position in our sky, its orbit, or physics in general (Why be bothered by reality?).
When Mars is at opposition, which means that it is opposite the sun in our sky, they say that it will be as large as the full moon. From now until about 2014, we are about as far away (at opposition) as we can get from Mars, which makes it appear smaller and dimmer in our sky than normal at that time. Mars will still look like a decently bright star, but that’s about it.
In 2003 Mars was in opposition in August. In 2009, Mars is NOT in opposition at all, but will reach opposition at the end of January 2010. It’s magnitude in August is not -2.9 as claimed, but about +1, which is MUCH dimmer. The reality is that nothing amazing is happening with Mars, except for our NASA and ESA space missions there.
What would it take for the hoax to be true???
Hypothetically, if it were possible for Mars to be as large as the full moon, either Mars would have to be made bigger ….
Or it would have to move MUCH closer…
A very reputable link with an enormous amount of info on Mars is here.
The Clark Planetarium solar system fact sheet can be downloaded here.