Is it possible for Mars to be as large as the moon when it is closest to the earth?

Question

A friend of mine insists this is going to happen on Aug 27th because Mars will be 43 million miles from earth. I can't imagine this happening under any circumstances. Am I right?

Answer 1

Your friend is rather gullible if he believes an implausible Baron Munchausen fairy tale like that without first checking whether NASA or other well-respected space websites can confirm the story. And you are quite right. It is, as you suspected, a load of old baloney,

Your friend has plainly received the hoax e-mail going round, the text of which has been quoted by other posters. It is based on a garbled and distorted version of events on August 27th 2003 when there was a close approach of Mars to Earth, but it now circulates with no year-date attached, so that people infer (wrongly) it must mean 2007.

GROUNDS TO BE SUSPICIOUS

A whopping big clue that the hoaxsters don't know what they are talking about when it comes to the Moon is that there is no mention of the Lunar Eclipse due on August 28th 2007.

Given the interest people have shown in solar and lunar eclipses for four millennia, this is a staggering omission for a group of people posing as publicists for exciting news about astronomical events coming up shortly.

If they don't even know there is a lunar eclipse in the offing, how reliable do you think the rest of their information is going to be?

IS THERE ANY TRUTH AT ALL IN WHAT THE E-MAIL SAYS?

These hoax e-mails circulate every summer. Loads of people must get them because Yahoo! Answers gets loads of questions on this subject.

Mars WILL look about the same size and brightness as another celestial body on 27th August, That much is true.

But that body is NOT the Moon, but ALDEBARAN, the bright red giant that is the eye of the bull and the brightest star in Taurus. Bit of a big mistake to make, that, wouldn't you say?

Mars will also be very close to Aldebaran in the sky too on 27th August 2007. Mars will be about +0.7 magnitude and Aldebaran is +0.85 magnitude. (A Full Moon is -12.7 magnitude, which means, with a 13.4 difference in magnitude from Mars, the Moon is 200,000 brighter than Mars!)

SIDE BY SIDE?

You can see where the Moon is yourself, and it is nowhere near Mars and Aldebaran. So Mars will not be appearing "side by side"
with the Moon. Nor will it be as large or as bright as the Moon as the e-mail claims.

ONCE UPON A TIME

Once upon a time a long time ago (about 60,000 BC) there was a close approach of Mars to Earth of about 34.65 million miles..

Mars did not come that close to Earth again until 27th August 2003. That was worth remarking upon as a memorable occasion and received publicity. These occasions are called perihelic oppositions.

Mars (magnitude -2.9) was marginally brighter than Jupiter (magnitude -2.8) on that date in 2003. However Venus which is both larger than Mars and nearer than Mars is (as you might expect) always brighter than Mars and varies between magnitude -3.8 and - 4.6.

So the statement in the hoax e-mail that Mars is about to become the brightest planet in the night sky is untrue.

The hoaxers do not know much about astronomy. They just sensationalise and distort the limited facts they have managed to pick up without properly understanding them or their implications.

As Venus has never been seen as large as the Moon and Venus is always brighter than Mars, it follows that Mars will not be seen to be as large as the Moon not on 27th August nor at any other time.

The naive belief that it "could be" that large this time just reveals the hoaxers' lack of understanding of how the Sun's gravity keeps the planets in stable orbits, which means the extent to which they vary in their positions is calculable and predictable.

Humanity has been studying and predicting the planets and their orbits for 4,000 years and writing their findings up in almanacs and suddenly someone with no credentials or track record in the world of astronomy comes along and declares "an unexpected dramatic change in a stable orbit is about to occur", wlthout explaining why that should be so. And expects to be believed!?

So the hoaxers do not understand that planetary orbits have been observed and carefully calculated and predicted for 4,000 years, and that professional astronomers would already know about this if what they say was true!

The hoaxers, however, seem to be suggesting that planets behave unpredictably and chaotically without any pattern or sense to that behaviour, and further, that they the hoaxers, like the Delphic Oracle of old, have unique divination powers and are passing on their knowledge, to which they alone are privy, to lucky old you.

Whereas all they are in fact passing on is misinformation based on their ignorance.

Mars, even at its nearest in 2003, was 140 times as far away as the Moon, and it is only twice its size (Equatorial radius of Mars = 3,402.5 km. Equatorial radius of the Moon = 1,738.14 km.).

So how could an object that is twice the size of the Moon but at least 140 times as far away (more like 220 times as far away in December 2007 when it will be 55 million miles away) (more like 420 times as far away on 27th August 2007 when it will be 105 million miles away) ever look as big as the Moon? Does a tomato a quarter of a mile away look as big as a cherry held at arm's length? I think not!

The only way Mars could ever appear as large as the Moon is if it were to get as close as half a million miles away,

If it did do that, it would be a disaster, causing huge tidal waves on Earth and tsunamai such as we have not seen the like of before. It would not be a thing to gawp at, and say "Oh wow! Awesome!" and tell all your friends to stay up and look out for it at 12.30 am !

But of course it won't do that (come within half a million miles of Earth) as Mars has a stable orbit.

The hoaxsters have sent out the same e-mail every summer as regards 27 August 2004, 27 August 2005, 27 August 2006 and now 27 August 2007. Again revealing their ignorance of how the Solar System works. Mars has a year that equals 1.88 Earth years and as a result only comes close to us once every 26 months: on 27th August 2003, and then not again until 30th October 2005 and then not again until 18th December 2007.

The idea of it having a close approach on the same date every year is nonsense therefore, it is not like a wedding anniversary or a birthday or Mothers' Day, As the hoaxsters seem to believe,

If anyone had have craned their necks and looked at the skies at 12.30 am on 27 August 2004 or 27th August 2006, all they would have got for their efforts was a stiff neck. As Mars was on the far side of the Sun on those two occasions and nowhere to be seen, as it was hidden behind the Sun's glare.

That is how much the hoaxsters know about astronomy. That is how accurate and worthless their predictions are. Nobody should be taken in by their "knowledge" and nobody should copy and spread their e-mail to others so as "to pass on the exciting news" they have just received.

Snopes.com (see link) have a useful article on the hoax.

Answer 2

You are correct, it's impossible for Mars to appear to be as big as the moon. If it ever did become that large in the sky, it would only be because Mars got sent on a collision course with the Earth because it's and likely our orbit too about the Sun were disrupted. Short of another star passing through the Solar System, there's no way this can happen because stars in our region of space are on average light years apart. The odds of that happening are virtually non-existant compared even to the risk of us being blindsided by an asteroid or comet out of the blue. The danger of that is very real, and far more likely than Mars getting close enough to use to look as big as the Moon does. Therefore, your friend got completely wrong and inaccurate information. In fact, Mars will not come within 43 million miles of us this year, even though the next close approach to us will take place this December. Even them, it will be much farther away from us than 43 million miles.

Answer 3

Your friend is a victim of a completely wrong and very sneaky hoax. And you're right.

At the closest approach Mars is 36 million miles away.
For it to appear as large as the moon, it would have to be (ummm, multiply then carry the 2, darn I dropped my calculator...). Well, never mind the exact number but Mars is about twice the diameter of the moon so would have to be only about twice as far from Earth as the moon to appear the same size - that would be about 725,000 kilometers.
That is less than 2% of its current minimum distance.
If Mars was going to be that close to Earth in a couple of weeks, it would already be huge in our night sky.

And it would be all you'd see on CNN and the evening news and in the newspapers and on every online news service and...

Answer 4

Tell your friend that there is no way that Mars can look as bug as the Moon.
There are people in the net posting this Bull.
When Mars is at it's closest point to Earth, it won't even look as bug as a ripe Grape.
It will look to be about the size of a small pea held at arm length.
And also tell him not to believe what he reads, unless it comes from a really good source, and don't believe nothing he hears, unless it can be backed up by the true thing.

Answer 5

The event has come and gone. On August 27, 2003, the orbital paths of Earth and Mars brought them to within 34.65 million miles of one another -- closer than at any other time in the past 50,000 years. Though Mars never actually appeared "as large as the full moon to the naked eye," the red planet did vividly dominate the night sky for a time, making 2003's "close encounter" a spectacular, "once in a lifetime" event indeed for astronomers, space enthusiasts, and ordinary observers alike.

Answer 6

You are correct. It's not possible, in fact its a hoax.

Some fools are spreading it by emails that Mars will look as big as the Moon. It will not. On Aug. 27, Mars will look pretty much like it looks now, shining as a very bright star-like point of light. With a telescope, of course, you can make it as big as the moon.

Answer 7

The only big red thing in the sky on August 27th/28th (depending where you are in the world) will be the moon itself as there will be a total eclipse of the full moon that night. If you haven't seen a total lunar eclipse, don't miss it, they are spectacular. Unlike a total solar eclipse which can only be seen along a very narrow strip, a total lunar eclipse is seen from everywhere you can see the moon. It is also completely safe to look at a lunar eclipse with the naked eye or through a telescope or binoculars.

Answer 8

Absolutely no way. For mars to be seen that big it's got be so close that it would disrup Earth's orbit so badly that I bet we'd be dead a few years later due to changes in climate/seasons.

I hate that mail too...

Answer 9

This is incorrect. If such nonsense happened, ether mars would grow to an extremely enormous size, or it would move closer to Earth, making it possible for astronauts to travel there.
Have your friend ask a personal astronaut, and see what he does.

Answer 10

Your imagination is correct -- Mars will look like a point of light in the night sky just like the stars around it, on the 27th. Actually, it will be dimmer than a lot of stars.

Oh, how I wish this hoax would just go-away.

.

Answer 11

I am glad to see you are thinking for yourself, and not one of these people getting information on the web or through friends and spreading it around without checking the validity.

You came to the right place - read the answers above (and tell your friend from me, he's a jerk).