You won鈥檛 be able to spot the Mars rover, but by the end of July the red planet will be the closest and brightest it has been in 15 years.

Every two years, Mars completes its orbit around the sun to align with Earth in a straight line on the directly opposite side from the sun, in a position called 鈥渙pposition.鈥�

This year, the date of alignment is July 27. The bi-annual event occurs every 26 months, but because distances can vary greatly due to the planets鈥� different elliptical orbital patterns, every 15 or 17 years the opposition occurs closer to the sun. That鈥檚 why Mars appears brighter in the sky.

In fact, stargazers won鈥檛 see the planet this vibrant and detailed again until 2035.

鈥淭his is not an event to miss,鈥� said Paul Delaney, a York University astronomy professor and director of the . The university will be hosting a 鈥溾�� free public viewing on weeknights, from July 25 to Aug. 1.

Optimal viewing is with scientific telescopes, such as the ones York will have for public use at the observatory. Viewers will be able to see ice caps and surface markings on Mars.

鈥淓verybody has a mind鈥檚 eye view of what they鈥檙e going to see. It鈥檚 nice to put reality to that,鈥� Delaney told CTVNews.ca.

Mars will be about 57 million km away by the end of the month, a little over one million km further than in 2003 when it was the closest it had been in 60,000 years.

But be wary of the 鈥淢ars hoax,鈥� said Delaney. That鈥檚 the name given to the falsehood that circulated 15 years ago when people were convinced that Mars would appear to the naked eye as large as the full Moon. Not so, Delaney said.

鈥淭he little disc (that is Mars) is reasonably large through a telescope,鈥� he said. Don鈥檛 expect to see anything awe-inspiring without one. With the naked eye or a set of binoculars, viewers won鈥檛 be able to see much at all. You鈥檒l be able to spot the dusty-hued planet since it will be the brightest speck in the sky when twilight ends (when the sun sets in the west, Mars rises in the east) but stick with the experts for the best view.

Naturally, some viewers end up disappointed. 鈥淚t鈥檚 not a Hubble Space Telescope,鈥� said Delaney of common university stargazing tools. There is a higher risk of disappointment this year due to the dust storm on the planet that trapped the Mars rover. The storm could obscure some details.

Still, this summer鈥檚 Mars opposition is an opportunity that won鈥檛 come along again for a while. For a lot of amateur astronomers, Mars is an impressive sight, Delaney said.

鈥淚t becomes a real tangible world to them,鈥� he said.