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 this week's show will still get a few good weeks of viewing.
"Although [Tuesday was] 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 a hundred times, Mars would have had the same angular size as the full moon seen with the naked eye."
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