Orbiting spacecraft have used radar to reveal mountains, valleys, and canyons on Venus.
Most of the surface, however, has large areas of volcanoes surrounded by plains of lava.
Figure25.13is an image made by a computer using radar data. It shows a volcano called
Maat Mons, with lava beds in the foreground. The reddish-orange color is close to what
scientists think the color of sunlight would look like on the surface of Venus.
Figure 25.13: This image of Maat Mons was generated from radar data. The surface of
Venus has many mountains, volcanoes, and plains of lava. ( 10 )
Motion and Appearance
Venus is the only planet that rotates clockwise as viewed from its North pole, in a direction
opposite to the direction it orbits the Sun. It turns slowly in the reverse direction, making
one turn every 243 days. This is longer than a year on Venus—it takes Venus only 224 days
to orbit the Sun.
Because the orbit of Venus is inside Earth’s orbit, Venus always appears close to the Sun.
When Venus rises early in the morning, just before the Sun rises, it is sometimes called “the
morning star.” When it sets in the evening, just after the Sun sets, it may be called “the
evening star.” Venus’ clouds reflect sunlight very well. As a result, Venus is very bright.
When it is visible, Venus is the brightest object in the sky besides the sun and the Moon.
Like Mercury, Venus has no moon.