Star-struck lovers need only look to the skies for inspiration this Valentine's day.

A satellite orbiting Mars has sent back a valentine's message just in time for 14 February.

Pictures show a heart-shaped Martian plateau in the south polar region of the red planet.

Nasa has released the pictures onto its web site so lovers can e-mail them as an alternative to the usual padded red card or roses.

Dark side

Nasa's Jet Propulsion Laboratory at Pasadena in California announced that the Mars Global Surveyor spacecraft had captured a lovely view of a bright, heart-shaped area of the planet measuring 255 metres across.

But be warned the heart has a dark side. It is surrounded by a layer of dark rough terrain.

The pictures were taken in a late southern spring in a region of the planet where for the winter and most of the spring it is covered in a bright frost.

Mars Global Surveyor is the first mission in a long-term program of Mars exploration.

The asteroid of love

In another Valentine's day special a Near spacecraft is due to explore an asteroid named after the Greek god of love "Eros" on Monday.

Experts are calling it an unprecedented chance to gain a better understanding of the space rocks.

It is also the first space flight to operate beyond the orbit of Mars while solar powered.