Philips Atlas of the Universe

Hubble Views of Mars

E

xcellent images of Mars have been obtained from the

Hubble Space Telescope, which has the advantage of

being able to monitor the planet over long periods. (Note

that the images given here have north at the top, as is the

NASA custom.)

The Hubble results were particularly valuable in 1997,

prior to the 4 July Pathfinder touchdown in the region of

the Ares Vallis and the arrival of Mars Global Surveyor in

the following September. Fortunately there were no wide-

spread dust-storms of the type which hampered the initial

work of Mariner 9 in 1971.

Dust-storms and ice clouds can be followed, giving

valuable information about the circulation and behaviour

of the Martian atmosphere. The Hubble Space Telescope

can also keep track of the changes in the polar ice caps.

[Credit: Steve Lee (University of Colorado), Phil James

(University of Toledo), and Mike Wolff (University of

Toledo), and NASA.]

ATLAS OF THE UNIVERSE

 Mars: Hubble Space

Telescope. North is at the

top. Comparison of the two

images above, taken on

17 May and 27 June 1997,

reveals that a dust storm has

developed in the intervening

period. It is visible as a streak

of yellow cloud towards the

southern edge of Mars’ disk

in the June image. It fills the

Valles Marineris canyons.

Thick water ice clouds can

be seen towards the

northwest in both images.

The north polar cap is also

well seen. The south polar

cap, however, is tilted away

from us, and only the polar

hood – made up of water

ice clouds – is visible. The

image below shows the

equatorial region of the

planet on 27 June 1997. The

green cross marks the

Pathfinder landing site. The

dust storm is well seen,

tracing the Valles Marineris

canyon system. The images

were taken by the Wide Field

and Planetary Camera on the

Hubble Space Telescope.

 Mars: Hubble Space

Telescope. North is at the

top. The south polar ice is

evident, as is the frost in the

north. Syrtis Major is seen to

the right, Acidalia Planitia

lower left, Sabaeus near the

centre of the image. Hellas is

visible below Syrtis Major,

but is not cloud-filled.

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