Mars at opposition before closest approach in a decade

Last week, Mercury stole the show. Now it's Mars' turn.

On Sunday morning, Mars, Earth and the sun will line up perfectly in the sky. This once-every-two-years event is called Mars opposition. That's because Mars and the sun will be on opposite sides of Earth.

Right now, Mars is about 77million kilometresfrom us, coming ever closer until May 30, when the red planet passes within 75.3million kilometres. That will be Mars' closest approach in 10years. In 2018, Mars will get a lot chummier, passing within a mere 58million kilometres.

The modern-day record of 55.7 million kilometresbetween Earth and Mars was set in 2003. That won't be surpassed until the year 2287, according to NASA.

At the other end of the scale, Earth and Mars can be as much as 400million kilometresapart when they wind up on opposite sides of the sun every couple years.

May is proving a busy month for stargazers.

On May 9, Mercury passed directly between Earth and the sun, resembling a black dot against our vast, bright star.

Telescopes or high-powered binoculars were needed to see that Mercury transit, which occurs just 13 times or so a century. Nothing fancy is needed to gaze upon Mars just your eyes.

Great views well into June

Sky-watchers, gazing to the southeast at nightfall, can enjoy a brighter, seemingly bigger Mars well into June. A full moon, on May 21, will add to the viewing pleasure.

The Hubble Space Telescope already is zooming in for pictures. On Thursday, the Space Telescope Science Institute in Baltimore released a snapshot of Mars taken May 12 from 80million kilometresout. The stunning image shows details as small as 30to 50 kilometresacross.