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BBC Tuesday, 12 June, 2001, 12:41 GMT 13:41 UKMars set to dazzle
By BBC News Online science editor Dr David Whitehouse
On Tuesday, Mars is at its brightest. It is also nearly at its closest approach to Earth.
Technically, the Red Planet is in opposition. This means the Earth lies directly between the Sun and Mars. You should find it due south at local midnight and in the best observation position for many years - certainly since 1988.
Astronomers, professional and amateur, have turned their telescopes towards the planet, hoping to capture some spectacular images.
Mars and the Earth are approaching each other. The pair are closest together on 21 - 22 June when they will be 67 million kilometres apart (41 million miles).
Rusty planet
The "star" with the red, dusky light that dominates the night sky at midnight is definitely worth a look. Indeed, viewed through my own telescope on recent nights I could make out markings on its surface and the suggestion of a whitish polar cap.
But you do not need a telescope to go out and admire Mars' light and to see why the ancients dubbed it the God of War because it reminded them of a drop of blood in the sky. The red colour, incidentally, comes from iron oxide on its surface. Mars is rusty.
Odyssey
It might be the best opposition in years but observers from northern latitudes will see Mars low-down on the Southern horizon. Although it only reaches 12 degrees above the horizon it cannot be missed because of its striking red colour.
Observers in the Southern Hemisphere are ideally placed, with Mars passing high overhead.
Satellite mapping
Mars oppositions occur every two years and two months. This one is particularly good as the planet is relatively close to the Earth and therefore appears larger than usual. This opposition is a preview for the next one in 2003, which will be truly spectacular for Northern Hemisphere observers.
Although observing surface features on Mars is something that really excites astronomers, Earth-based observations of Mars are not as valuable as they used to be. This is because circling Mars is Nasa's Mars Global Surveyor. This spacecraft has recently completed 10,000 mapping orbits.
Despite this, astronomers are keeping a close watch on Mars in the coming months. Some predict that there may be planet-wide dust storms as Mars approaches perihelion - its closest to the Sun - in October.
By then, however, it will be receding into the distance once more as seen from Earth, but we should get another close-up view when the Mars Odyssey 2001 spacecraft arrives that month.
-- Anonymous, June 12, 2001
I had my telescope out last night and will again tonight...it was beautiful!
-- Anonymous, June 13, 2001