Painted green by a flashlight, astronomer Dennis Mammana of California points out Mars to onlookers on Aug. 26, 2003, when Mars was particularly close to Earth. Photo credit: Thad V'Soske via NASA Science.

Mars came particularly close to Earth back in 2003, and ever since we have been experiencing an annual email hoax convincing us that we will once again have a once-in-a-lifetime opportunity to see Mars as big as the Moon.

The cycle is happing again (view an interactive orbit map), with an expected closer encounter to happen this August. However, when you look up into the sky next month, you won't see the Moon and the Red Planet together as temporary twins.

The close approach that occurred on August 27, 2003 was in deed the most near we have been to Mars in some 60,000 years. And, we are talking only 56 million kilometers (about 34.8 million miles) close. Take an important comparative note here that the Moon sits anywhere between about 363,000 and 406,000 km from Earth (learn more about the Moon). However, near approaches have routinely happened many times in between 58,000 B.C. and 2003, with more recent occurrences in 1845 and 1924, which were only around 50 thousand km less. Not so much difference in the scale of the Solar System.

What's great about this particular hoax is that it is a perfect opportunity for citizen scientists to learn (or re-learn) about planetary orbits, and to help spread the excitement about the real physics of our Solar System. It is truly incredible that all of these massive objects are spinning around in such predictable harmony, and that anyone can discover so much information about how it all works.

For example, NASA's Jet Propulsion Laboratory provides an online system, called JPL HORIZONS, for reporting the ephemeris (positions of astronomical bodies) for planets, planetary satellites, spacecraft, and other dynamic points throughout or Solar System. The distances can also be calculated to your personal location on Earth from anytime since January 4, 1900 up through January 3, 2100.

So, watch your email inbox carefully over the next several weeks (and make sure you don't download any computer viruses), and help your friends learn more about the reality of our planetary neighbor Mars, since you--or your children--might travel there someday!

"Mars Spectacular" from Snopes.com :: [ READ HOAX Report ]

"Beware the Mars Hoax" :: Science@NASA :: July 7, 2005 :: [ READ ]

Powerpoint Presentation via Email Hoax received by DPR  :: Mars is So Close Hoax

Interactive Mars-Earth-Sun Orbit Map [ TRY IT ]
From Windows to the Universe (requires Flash)

Try running the simulation backwards to August 27, 2003 and see how close Mars really was.

 How close was Mars on your birth date?

JPL HORIZONS Ephemeris Calculation System [ TRY IT ]