National Geographic News
Tuesday 18 December 2007
Mars Closest
to Earth Tonight;
Best View Until 2016
by Kelly Hearn for National Geographic News
The bright yellowish-orange "star" poised above the constellation Gemini is actually the planet Mars, and tonight the icy world will make its closest approach to Earth until 2016.
Earth passes Mars every 26 months, overtaking it in an "orbital race" as both bodies go around the sun.
(Explore planetary orbits using an interactive solar system.)
"Earth comes close to Mars because our planet is moving faster in its orbit, catching up to and passing Mars," said Jaymie Mark Matthews, an astronomer at Canada's University of British Columbia.
Tonight's passage happens while Mars is in retrograde motion, or appearing to move westward across the night sky.
"Thus, for the three months around closest approach, the yellowish-orange planet will appear to move slowly backward from the constellation Gemini into Taurus," said Edward Murphy, an astronomer at the University of Virginia.
The exact distance between the two worlds varies during a close encounter, because the planets' orbits are elliptical.
Murphy calculates that today Earth is roughly 55,000,000 miles (88,000,000 kilometers) apart from Mars, a figure backed by Matthews.
But experts say tonight's glimpse of the red planet will be nothing compared to the show-stopping passage of 27 August 2003, when a mere 35,000,000 miles (56,000,000 kilometers) stood between the two bodies.
"That was when the red planet came closer than it had ever been since the time Neanderthals walked the Earth," Matthews said.
Best Views
Though Mars won't be as close to Earth as it was in 2003, tonight's viewing might be better for some sky-watchers.
That's because Mars won't be as close to the Earth's horizon as it was four years ago, thanks to the astronomical geometry of this year's planetary opposition.
Opposition is when Earth is between the sun and a planet, so the planet appears in the opposite side of the sky as the sun. During the Northern Hemisphere's winter Earth tilts away from the sun and toward Mars.
"That's a good sign for sky-gazers at latitudes of about 40 to 45 degrees north," Matthews said.
"For them, Mars will pass almost straight overhead during the night."
And for those at mid-northern latitudes, Mars will be up all night long, Murphy said.
Mars fans who miss out on tonight's show will still get a few good weeks of viewing.
"Although tonight is the night of closest approach, the distance between Earth and Mars is changing very slowly," Matthews said.
"Mars will look good all month and will still be very good until late January."
People with even the most basic telescopes should be able to see Mars's bright icy poles and dark features, according to Space.com.
The planet will also be visible with the naked eye, and its opposition means that it appears in full-phase, similar to a full moon.
But Matthews cautioned against unrealistic expectations.
"Ignore email messages saying that Mars will look as big as the full moon in the sky," he said.
(Read: "'Mars Spectacular' E-Mail Hoax Spins On" [August 26, 2005].)
"Even in August 2003, at a telescopic magnification of about 100 times, Mars would have had the same angular size as the full moon seen with the naked eye."
===================
by Jonathan Richman & The Modern Lovers
Here come the Martian Martians
And they're riding on their Martian bike
Well, we have to find out right now
What kind of ice cream do the Martians like?
Here come the Martian Martians
Why staying in such a cheap hotel?
Maybe we should help out the Martians
Looks like the Martians ain't doin' too well.
Martian time time time
Well, it's Martian rhyme time
We got a Martian rhyme for Martian Martian time
And the Martians got notebooks in their little hand
Well they're strangers in this land
Martian time It's Martian Martian time
Well, here come the Martian Martains.
They're trying to fight with rocks and sticks
Don't the Martians know better?
Looks like they're up to their same old tricks.
Well, here come the Martian Martians,
They got notebooks in their hand.
What are they trying to write down?
I guess they must be strangers in this land.
Martian rhyme rhyme
Well, Martian time time
Well, you got Martian rhymes for Martian Martian time.
See, the Martians have notebooks in their little hand.
See, they're still strangers in this land.
Martian time, it's Martian Martian time.
Well, here come the Martians
Baking up a Martian cake
We better find out right now
What kind of flavor do these Martians make.
Well, here come the Martian Martians,
There're Martian schoolgirls too
Well, I like the Martian schoolgirls,
And I hope they like me too.
Martian rhyme rhyme rhyme
It's Martian time time time
You got the Martian rhymes for Martian Martian time.
The Martians have notebooks in their little hand
Because they're strangers in this land.
Martian rhyme, it's Martian Martian time.
Well, here come the Martian Martians
Well, they're baking up a Martian pie
I hope the Martians like me
And give some to I.
Well, here come the Martian Martians,
Well, they're setting up a Kool-Aid stand.
Where's their financial advisor?
Somebody should take him by the hand.
Martian rhyme rhyme rhyme
Martian time time time
You got a Martian rhyme for Martian Martian time.
And the Martians have notebooks in their little hand
They're still strangers in this land
Martian rhyme, it's Martian Martian time.
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